ArticlePDF Available

Mars ain’t the kind of place to raise your kid: ethical implications of pregnancy on missions to colonize other planets

Authors:

Abstract

The colonization of a new planet will inevitably bring about new bioethical issues. One is the possibility of pregnancy during the mission. During the journey to the target planet or moon, and for the first couple of years before a colony has been established and the colony has been accommodated for children, a pregnancy would jeopardize the safety of the crew and the wellbeing of the child. The principal concern with a pregnancy during an interplanetary mission is that it could put the entire crew in danger. Resources such as air, food, and medical supplies will be limited and calculated to keep the crew members alive. We explore the bioethical concerns of near-future space travel.
R E S E A R C H Open Access
Mars aint the kind of place to raise your
kid: ethical implications of pregnancy on
missions to colonize other planets
Haley Schuster and Steven L. Peck
*
* Correspondence: steven_peck@
byu.edu
Originally presented at the Annual
International Mars Society
Convention, Washington, DC
August 13-16, 2015
Biology Department, Brigham
Young University, Provo, UT 84602,
USA
Abstract
The colonization of a new planet will inevitably bring about new bioethical issues.
One is the possibility of pregnancy during the mission. During the journey to the
target planet or moon, and for the first couple of years before a colony has been
established and the colony has been accommodated for children, a pregnancy
would jeopardize the safety of the crew and the wellbeing of the child. The principal
concern with a pregnancy during an interplanetary mission is that it could put the
entire crew in danger. Resources such as air, food, and medical supplies will be
limited and calculated to keep the crew members alive. We explore the bioethical
concerns of near-future space travel.
Introduction
A non-profit organization called Mars One has begun to sort through candidates to
take the nine month journey to Mars and establish a human colony with the goal to
make Mars habitable. The colonization of a new planet will inevitably bring about new
bioethical issues. One is that the possibility of pregnancy during the mission could
jeopardize the safety of the crew and the wellbeing of the child. Mars One has not
stated a hard-fast rule about preventing pregnancy, only that it will advise against it.
Solutions offered include having the astronauts permanently or temporarily sterilized
which would be the most certain way to prevent pregnancy. Mars Ones intention to
colonize a planet opens up a number of questions that it is not too early to start ex-
ploring. For example, what are the ethical implications of a space program requiring
the astronauts to be sterilized? What are the implications of potential reproduction in
space? A closer look at human reproduction in light of future space travel, however, is
warranted. Especially in light of calls for further consideration of womens issues in
spaceflight (Drudi and Grenon, 2014). We focus especially on the implication of preg-
nancy during space fight and use Mars One as an illustration for our exploration.
Pregnancy in space
Pregnancy during a mission such as Mars One is dangerous because it could put the
entire crew in danger. Resources such as air, food, and medical supplies will be limited
and carefully gauged to keep the crew members alive. An unexpected addition to the
© 2016 The Author(s). Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International
License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium,
provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and
indicate if changes were made.
Schuster and Peck Life Sciences, Society and Policy (2016) 12:10
DOI 10.1186/s40504-016-0043-5
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
crew could put these carefully managed resource and risk calculations out of balance.
Moreover, anticipating such a contingency greatly increases the complexity and cost of
a mission. A pregnancy and child would put a strain on the mother and compromise
her ability to continue her necessary duties for the mission, therefore putting additional
workload on the remainder of the crew. Other crew members would be forced to com-
pensate but with few crewmembers (only four crew members are proposed by Mars
One) it would still be detrimental to have one of them facing the additional physical
challenges of pregnancy especially if there are complications due to the potential for
significant risk to the mothers life. These dangers mean that preventing pregnancy will
be critical to the mission, suggesting that individuals selected for the mission may need
to be willing to give up their fertility permanently or temporarily for the well-being of
the crew and the mission.
Pregnancy in lower gravity environments has been shown to be feasible, but not with-
out challenges. Studies by Ijiri (2004) and Ronca (2003), show that animal pregnancies
and births occur in microgravity, indicating that such events could happen in the 40 %
gravity on Mars as well. However, mammal births on the International Space Station
(ISS) cited by Ronca were found to be more difficult during labor and were more likely
to result in stillbirths. This finding implies that a human birth would also be more diffi-
cult in microgravity.
Further evidence suggests that environmental factors such as low gravity and the
presence of cosmic radiation could have a detrimental effect on the fetus during devel-
opment. Substantial data has demonstrated that radiation can cause gross malforma-
tions, growth retardation, and central nervous system abnormalities in the fetus
(Straume, Blattnig, & Zeitlin, 2010).
Space agencies are already well aware of the dangers of cosmic radiation to astro-
nauts and measures are taken to provide adequate shielding, but the effects radiation
could have on a fetus have not been well-studied. The total amount of radiation astro-
nauts could potentially experience on their way to Mars was recently estimated by
equipment on the Curiosity rovers spacecraft as it was en route to Mars. The radiation
level was estimated to be about 0.66 Sv (Zeitlin et al. 2013). This amount falls within
Table 1 Failure rate of various forms of contraception (Contraception, 2015)
Birth control method Failure rate
Implant 0.05 %
Male sterilization (vasectomy) 0.15 %
Levonorgestrel IUD 0.2 %
Female sterilization (tubal ligation) 0.5 %
Copper Intrauterine Device (IUD) 0.8 %
Injection (shot)6%
Oral contraceptives (the pill)9%
Patch 9%
Hormonal vaginal contraceptive ring 9 %
Diaphragm 12 %
Male condom 18 %
Female condom 21 %
Spermicides 28 %
Schuster and Peck Life Sciences, Society and Policy (2016) 12:10 Page 2 of 8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
the range in which the risk of birth defects increases substantially (McCollough et al.
2007). Additionally, solar flare events can occur and temporarily increase the radiation
dose even if there is adequate shielding for normal conditions. If a Martian base were
established, the radiation on the surface of Mars could be even more problematic since
space suits cannot shield as much radiation as a habitat structure or spacecraft could,
so an astronaut who is pregnant would need to restrict the time she spends outside. Al-
though, a pregnant female astronaut would not likely fit EVA suits provided should
emergency use be needed.
In addition to the health concerns of a pregnant astronaut there is evidence that de-
creased gravity negatively affects fetal development. Experiments performed with preg-
nant rats in the NASA Space Shuttle provide evidence that lack of gravity disrupts the
development of the vestibular system (Ronca et al. 2008). This finding means a child
conceived during the flight to Mars could have problems balancing and orienting him
or herself on the surface of Mars. Studies using human bone marrow stem cells found
a significant effect on cells in microgravity and fewer cells were generated (Davis et al.,
1996). Since cell proliferation was decreased in these human stem cells, it is likely that
the space environment could cause the fetus to develop abnormally (e.g., see also
Zhang et al. 2016; Beck et al., 2012; Ogneva, 2015). A child with birth defects, or one
born prematurely, would be more difficult to care for in an environment with such lim-
ited resources. This suggests that bearing a healthy baby is less likely on such a mission,
and therefore the negative consequences of pregnancy suggest this possibility should be
actively mitigated against.
The health of mother and crew
Pregnancy on the mission would also pose a greater risk to the mother. Although one
or two of the astronauts will receive comprehensive medical training and medical
equipment to treat anticipated illnesses or injuries will be available, the crew will likely
not be prepared to assist with birth complications or provide care for a newborn.
Should something go wrong during the pregnancy or birth, the crew may not have the
skills or supplies necessary to keep the mother and child safe. Further, the confined en-
vironment of the ship and the lack of gravity could pose additional challenges for neo-
natal care. The wellbeing of the mother and child could be greatly compromised if
complications should arise. Surgeries have been completed successfully on rats in
microgravity (Campbell Mark et al. 2005), however the time in surgery was longer com-
pared with surgeries in Earth gravity. Moreover, despite the success of these surgeries,
it seems likely that microgravity would pose other unexpected challenges for human
surgery. For example, it has also been shown that microorganisms thrive in micro-
gravity environments (Horneck et al. 2010). Factors such as disease virulence, infect-
ability, and transference in microgravity are largely understudied. In addition,
resistance factors of disease organisms might also be modified in space. Researchers
suggest that pregnant women may be at greater risk for contracting an illness in space
(Santy & Jennings, 1992).
Pathogens may spread among the crew more easily in the cramped conditions of a
spacecraft. The observation that astronautsimmune systems are suppressed due to
microgravity is well established (Martinez et al. 2015) and it has been shown that im-
mune system dysregulation occurs during flight(Sams et al. 2015). NASA researchers
Schuster and Peck Life Sciences, Society and Policy (2016) 12:10 Page 3 of 8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
expect that an impaired immune system could pose a major risk for longer space
flights, such as the one to Mars. Connections between stress levels and changes in the
immune systems ability to react properly are well documented, which suggests that the
extra stress a pregnancy would surely cause will likely have a negative effect on the
mothers immune system. With an increased risk to the mother, it would be better to
take measures to prevent pregnancy for the health of the mother, as well as the greater
good of the crew and the mission.
Sex in space
Human sex drive has been found to persist when humans are isolated in a small group
for an extended time. At this time, NASAs policy forbids sex in space, and there have
been no confirmed instances of it happening, but the lengthy trip to Mars and even
starting a colony could result in sex occurring. There have been seven recorded preg-
nancies and more undisclosed due to privacy policies in remote Antarctic research sta-
tions, where small crews are isolated together for long months in similarly stressful and
dangerous environments (Stuster, 2011). This is unexpectedly high for a group of highly
trained, professional scientists. Thus, with a mixed gender crew, sexual intercourse is
likely during the years of the crews isolation on a mission to colonize Mars or any such
long term space exploration. Perhaps an effective training program could inspire crew
members to place solidarity of the group ahead of personal interests. Such a perspec-
tive, if possible to maintain, would greatly reduce the occurrences of sexual activity, but
it cannot guarantee abstinence. Therefore, extra precautions for such a long-duration
mission are necessary.
Pregnancy must have been enough of a problem or concern that in 2011, the U.S.
Antarctic Program instituted a new rule requiring all women of childbearing years to
take a pregnancy test before being cleared to live in Antarctica. Their reasoning for
prohibiting pregnant women is
Because clinics at U.S. stations are not equipped or staffed to provide adequate
prenatal care, manage obstetric emergencies, or perform abortions, medical
evacuation may be necessary. There are few transportation options during the
isolated Antarctic winter. Consequently, pregnancy puts not only the mother and
unborn child at risk but also the flight crews and other station personnel.(United
States Antarctic Program).
With long-duration space travel, such as the trip to Mars, these same concerns would
be even more important because evacuating or receiving necessary pregnancy-related
supplies would not be an option. Since there is no way to evacuate a pregnant woman
during a trip to Mars, preventing a pregnancy from even occurring becomes crucial,
thus the importance of temporary or permanent sterilization. Upon the announcement
of this new policy, some feared that this would result in women being treated differ-
ently or unfairly in the hiring process (Carmon, 2011). Similar concerns would arise
from a requirement for astronauts to be temporarily or permanently sterilized.
Terrestrial space flight analogs, that is, isolated confined environments such as Navy
ships and submarines can provide insight into this kind of problem. In the Navy, it has
been reported that pregnancies occurring while on duty on ships make up less than
Schuster and Peck Life Sciences, Society and Policy (2016) 12:10 Page 4 of 8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
one percent of the Total Force (Daniel, 2013). While this means there is only a small
number of pregnancies that occur in such situations, it does show that pregnancies do
in fact occur in such stressful, confined, rigid environments. According to the Navy
press release cited above, the low percentage is due to the educational programs the
Navy provides about contraception methods and family planning. It is probably also
safe to assume that getting pregnant while on operational duty is highly discouraged in
their training. But, despite all the training the Navy provides, pregnancies do still occur.
One study performed by the Center for Naval Analysis reported that every year a sig-
nificant number of unplanned personnel losses from Navy ships are due to pregnancy
(Garcia, 1999), although the actual number is not available. This data is for the whole
Navy, on ships with much bigger crews than the four person Mars crew, but it does
provide information that pregnancies do happen in high stress, confined environments
such as those on Navy ships.
The issue of a pregnancy on a submarine has only come to light recently because
only a few countries allowed women to serve on submarines (Kane and Horn 2001).
Starting in 2016, women will be serving on United States Navy submarines. This new
development has been met with controversy and opposition. Some of the arguments
against adding women to submarine crews involve the possibility of women getting
pregnant during tours of duty. One concern is the potential contamination of the fil-
tered air and the presence of high levels of carbon dioxide, both of which could be
harmful to a developing fetus (Kane and Horn 2001). At present, the effects of sub-
marine air on fetus development have not been studied (Kane and Horn 2001). Mars
spaceships and colonies will similarly be totally confined, self-sustaining environ-
ments, so contaminated air and high levels of carbon dioxide could be a problem for
them as well.
While these comparable situations can be helpful in predicting potential issues in a
Mars trip, the consequences of a pregnancy are not as great. Pregnant women in these
situations can be removed from isolated and dangerous situations, and can go home. A
rescue mission for astronauts would take longer than a full term pregnancy to orches-
trate. Further, the dangers associated with a pregnancy are not as high in an Earth grav-
ity environment. Therefore, the consequences of using less effective contraceptive
measures are not as great. Astronauts on a Mars mission will need to use more effect-
ive methods.
Contraception in space
There is a possibility that it could be easier to become pregnant in microgravity. Radi-
ation exposure will likely reduce sperm count, but there is evidence that suggests sperm
cells swim faster in microgravity. One study found that sperm is affected by small
changes in gravity and found that fertilization in hypergravity was slowed down (Tash,
Kim, Schuber, Seibt, & Kinsey, 2001). A similar study in microgravity, or even reduced
gravity, still needs to be performed, but Tash, et al. propose that an opposite effect may
occur in microgravity. If fertilization could potentially occur faster, other contraceptive
methods may not be able to work as well, and therefore sterilization may be a more ef-
fective choice.
Table 1 shows the success rate of various forms of contraception (Contraception,
2015). The most effective methods of contraception are sterilization and long-acting
Schuster and Peck Life Sciences, Society and Policy (2016) 12:10 Page 5 of 8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
reversible contraception, which essentially amounts to temporary sterilization.
Sterilization methods, including permanent and temporary, are the only birth control
methods besides abstinence that are nearly one hundred percent effective (Suszynski
2014) each with less than 1 % failure rate (Contraception, 2015).
Permanent methods include vasectomy and female tubal ligations, and even hysterec-
tomy. Reversals of vasectomies and tubal ligations are possible, but they are costly and
there is a low success rate of regaining fertility.
Temporary sterilization methods include the copper intrauterine device (IUD), pro-
gesterone IUD, and progesterone implant. These can last for ten years, three or five
years, and 3 years, respectively. Depending on how long it takes a proposed colony to
be ready for children, the temporary methods may or may not last long enough, and re-
placements may be needed. All other birth control methods rely on human responsibil-
ity to regulate their effectiveness. The next best option after the sterilization methods is
the progestin shot given every three months and has a typical use failure rate of 6 %.
This and other methods such as condoms or the pillare less effective (ranging from 9
to 28 % failure rate) and require supplies and check-ups that may not be available on
the mission, whereas sterilization is a onetime procedure. The supplies and packaging
that would be required for non-sterilization contraception would take up precious
cargo space and may not even retain its effectiveness for the length of time needed; es-
pecially for the Mars One plan. Further, it is not known if the constant bombardment
of radiation on the contraceptives would decrease their effectiveness or not.
Despite the overwhelming evidence supporting the necessity of sterilization on a
Mars mission, specific ethical arguments have been advanced against the idea of
sterilization and even contraceptives in general, and similar arguments could be formed
against this requirement. In most ethical traditions, the right to reproduce is a funda-
mental freedom. Requiring permanent or temporary sterilization would infringe upon
the right of each astronaut to reproduce. The right to choose which medical procedures
are performed on ones body is also commonly upheld, and requiring astronauts to go
through the process of sterilization or use the temporary methods may hinder that
right as well. This policy may feel discriminatory against those that want to retain their
fertility or have personal objections to undergoing the procedures or using the tempor-
ary methods. To avoid forcing astronauts into doing something that goes against their
personal beliefs, it will be important for these requirements to be clearly laid out from
the time they are put in place. That way, a person who does not wish to fulfill the re-
quirement of becoming infertile may choose a different path. The necessity of being in-
fertile during a long duration space flight is so essential for the safety of the whole
crew, that the astronauts will have to give up their right to reproduce freely. While this
requirement may seem drastic or harsh, it will be necessary to prevent the crew mem-
bers from endangering each other.
Common arguments against contraceptives include claims that it goes against the
goals of a Mars colony, is anti-life, prevents people who could benefit humanity from
being born, leads to immoral behavior, and that it goes against many religious beliefs.
In this case, Mars astronauts may only need to be sterilized for a decade or so before a
colony is set up well for children, although the colonys child-readiness could likely
happen beyond their lifetimes or fertility years. Regarding arguments that contracep-
tives are effective enough, the catastrophic consequences of a mission pregnancy
Schuster and Peck Life Sciences, Society and Policy (2016) 12:10 Page 6 of 8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
suggest that sterilization is necessary to preserve the lives of the crew by preventing an
unexpected increase in resource requirements. The children born would have a higher
risk of intellectual and physical disabilities which would strain resources. Further, its
unlikely that sexual activity can be prevented. It is also possible that extended periods
of radiation on the surface of Mars may eventually make the astronauts sterile; it is a
risk inherent to the mission.
Those who see sterilization as morally wrong either from religious or deontological
perspectives may have to carefully consider participation in such a mission. Those with
such views do not have to be a part of the mission and they should not prevent others
from taking this safety precaution. The catastrophic nature of a pregnancy on such a
mission suggests that all crew members must take the necessary precautions to protect
against this possibility. The question still remains, however, if the responsibility of
avoiding pregnancy lies on all crew members, or only the ones capable of becoming
pregnant. If the goal is to decrease the chance of any crew member becoming preg-
nant as much as possible, then it would follow that all crew members must be per-
manently or temporarily infertile. The group as a whole needs to be infertile.
Sterilization would not be necessary for single sex crews or crews with women who
have undergone menopause.
Based on the evidence gathered thus far, sterilization appears to be the best choice of ac-
tion for preventing pregnancy during preliminary missions to Mars. A utilitarian approach
seems mandated to reduce negative consequences for the group as a whole. Therefore,
ethically, it seems desirable to require astronauts to be sterilized. Temporary or perman-
ent, sterilization is a more certain way to prevent the negative effects a pregnancy could
have on the entire crew such as danger to the mother, abnormalities in the fetus, and lim-
ited resources for the crew, and to better ensure the safety and well-being of all.
Conclusions
We have not discussed a number of other considerations that will require future work.
For example, the psychological stresses and harms that might come from a pregnancy
in space have not been considered. Others may want to further explore the ethical
question of requiring permanent or temporary sterilization from the perspective of dif-
ferent ethical perspectives such as differing religious orientations. One related ethical
question that should be explored is whether it is ethical to require the burden of preg-
nancy prevention to fall only on women. Additionally, how can the mission planners
avoid burdening only women with the responsibility of contraception if there are no
equally effective temporary contraceptive methods for men. Furthermore, the medical
effects of sterilization on women are more substantial and invasive, while vasectomy is
known to be safe and effective. Finally, if a woman were to conceive mid-mission, how
would current debates about abortion play out and should medical procedures and re-
sources be in place to make this option available? More research needs to be done to
better understand the dangers of pregnancy on such a long duration space mission.
Space agencies considering a mission to Mars (to visit or colonize) will want to con-
sider these and other ethical questions in order to better ensure the safety and well-
being of their crews.
Acknowledgements
With apologies to Elton Johns song Rocket Man.
Schuster and Peck Life Sciences, Society and Policy (2016) 12:10 Page 7 of 8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
Authorscontributions
HS wrote the initial paper upon which this was based; Peck added content and perspective. The individual contributions
are intermingled throughout the text, but contributions are about, HS 80 % and SLP 20 %. All authors read and approved
the final manuscript.
Authors' information
HS is a 2015 BS Neuroscience graduate from Brigham Young University. SLP is an Associate Professor of Biology at
Brigham Young University where he teaches and researches in computational ecology, bioethics and the history and
philosophy of biology.
Competing interests
The authors declare that they have no competing interests.
Received: 29 September 2015 Accepted: 9 August 2016
References
Beck M, Tabury K, Moreels M, Jacquet P, Van Oostveldt P, De Vos WH, Baatout S. Simulated microgravity decreases
apoptosis in fetal fibroblasts. Int J Mol Med. 2012;30:30913. http://dx.doi.org/10.3892/ijmm.2012.1001.
Campbell Mark R, Williams DR, Buckey JC, Kirkpatrick AW. Animal Surgery during Spaceflight on the Neurolab Shuttle
Mission. Aviat Space Environ Med. 2005;76(6):589. Print.
Carmon Irin. 2011. Want to Work in Antarctica? Take The Mandatory Pregnancy Test First. Jezebel. Retrieved from
http://jezebel.com/5739118/want-to-work-in-antarctica-take-the-mandatory-pregnancy-test-first
Contraception. (2015). Centers for Disease Control and Prevention. Retrieved from: http://www.cdc.gov/
reproductivehealth/unintendedpregnancy/contraception.htm
Daniel AL. (2013). CSADD Encourages Family Planning During Your Navy Career. Retrieved from: http://www.navy.mil/
submit/display.asp?story_id=71328
Davis TA, Wiesmann W, Kidwell W, Cannon T, Kerns L, Serke C, Lee KP. Effect of Spaceflight on Human Stem Cell
Hematopoiesis: Suppression of Erythropoiesis and Myelopoiesis. Journal of Leukocyte Biology. 1996;60(1), 69-76.
Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/8699125
Drudi L, Grenon SM. Womens Health in Spaceflight. Aviat Space Environ Med. 2014;85(6):64552. doi:10.3357/ASEM.3889.2014.
Garcia F. Women at sea: Unplanned losses and accession planning. Center for Naval Analyses. CRM. 1999;98-182.
Horneck G, Klaus DM, Mancinelli RL. Space microbiology. Microbiol Mol Biol Rev. 2010;74(1):12156.
Ijiri K. Ten years after medaka fish mated and laid eggs in space and further preparation for the life-cycle experiment
on ISS. Biol Sci Space. 2004;18(3):1389. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/15858359.
Kane J, Horn W. The Medical Implications of Women on Submarines. Groton, Ct: Naval Submarine Medical Research
Laboratory; 2001. Retrieved from: www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA400035.
Martinez E, Yoshida M, Candelario T, Hughes-Fulford M. Spaceflight and simulated microgravity cause a significant reduction
of key gene expression in early T-cell activation. Am J Physiol Regul Integr Comp Physiol. 2015;308(6):R4808.
McCollough C, Schueler B, Atwell T, Braun N, Regner D, Brown D, Leroy A. Radiation exposure and pregnancy: When
should we be concerned? Radiographics. 2007;27(4):909U5.
Ogneva IV. Early development under microgravity conditions. Biophysics. 2015;60(5):84958. doi:10.1134/S0006350915050140.
Ronca AE, Fritzsch B, Bruce LL, Alberts JR. Orbital spaceflight during pregnancy shapes function of mammalian
vestibular system. Behav Neurosci. 2008;122(1):22432.
Ronca AE. Studies toward birth and early mammalian development in space. Adv Space Res. 2003;32(8):148390.
Sams C, Stowe R, Uchakin P, Crucian B, Mehta S, Morukov B, Pierson D. Validation of procedures for monitoring
crewmember immune function (integrated immune). National Aeronatics and Space Agency (NASA). 2015.
Retrieved from: http://www.nasa.gov/mission_pages/station/research/experiments/632.html#images
Santy PA, Jennings RT. Human reproductive issues in space. Adv Space Res. 1992;12(2-3):1515.
Straume T, Blattnig S, Zeitlin C. Radiation hazards and the colonization of Mars: Brain, body, pregnancy, in-utero
development, cardio, cancer, degeneration. J Cosmol. 2010;12:39924033.
Stuster J. Bold Endeavors: Lessons from polar and space exploration. Annapolis: Naval Institute Press; 2011.
Suszynski M. The 11 Best Birth Control Options for Women. 2014. Retrieved from: http://www.everydayhealth.com/
sexual-health-pictures/the-11-best-birth-control-options-for-women.aspx#10.
Tash JS, Kim S, Schuber M, Seibt D, Kinsey W. Fertilization of sea urchin eggs and sperm motility are negatively
impacted under low hypergravitational forces significant to space flight. Biol Reprod. 2001;65(4):122431.
doi:10.1095/biolreprod65.4.1224.
Zeitlin C, Hassler DM, Cucinotta FA, Ehresmann B, Wimmer-Schweingruber RF, Brinza DE, Kang S, Weigle G, Bottcher S,
Bohm E, Burmeister S, Guo J, Kohler J, Martin C, Posner A, Rafkin S, Reitz G. Measurements of energetic particle
radiation in transit to Mars on the Mars Science Laboratory. Science. 2013;340(6136):10804.
Zhang S, Zheng D, Wu Y, Lin W, Chen Z, et al. Simulated microgravity using a rotary culture system compromises the in
vitro development of mouse preantral follicles. PLoS One. 2016;11(3):e0151062. doi:10.1371/journal.pone.0151062.
Schuster and Peck Life Sciences, Society and Policy (2016) 12:10 Page 8 of 8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
1.
2.
3.
4.
5.
6.
Terms and Conditions
Springer Nature journal content, brought to you courtesy of Springer Nature Customer Service Center GmbH (“Springer Nature”).
Springer Nature supports a reasonable amount of sharing of research papers by authors, subscribers and authorised users (“Users”), for small-
scale personal, non-commercial use provided that all copyright, trade and service marks and other proprietary notices are maintained. By
accessing, sharing, receiving or otherwise using the Springer Nature journal content you agree to these terms of use (“Terms”). For these
purposes, Springer Nature considers academic use (by researchers and students) to be non-commercial.
These Terms are supplementary and will apply in addition to any applicable website terms and conditions, a relevant site licence or a personal
subscription. These Terms will prevail over any conflict or ambiguity with regards to the relevant terms, a site licence or a personal subscription
(to the extent of the conflict or ambiguity only). For Creative Commons-licensed articles, the terms of the Creative Commons license used will
apply.
We collect and use personal data to provide access to the Springer Nature journal content. We may also use these personal data internally within
ResearchGate and Springer Nature and as agreed share it, in an anonymised way, for purposes of tracking, analysis and reporting. We will not
otherwise disclose your personal data outside the ResearchGate or the Springer Nature group of companies unless we have your permission as
detailed in the Privacy Policy.
While Users may use the Springer Nature journal content for small scale, personal non-commercial use, it is important to note that Users may
not:
use such content for the purpose of providing other users with access on a regular or large scale basis or as a means to circumvent access
control;
use such content where to do so would be considered a criminal or statutory offence in any jurisdiction, or gives rise to civil liability, or is
otherwise unlawful;
falsely or misleadingly imply or suggest endorsement, approval , sponsorship, or association unless explicitly agreed to by Springer Nature in
writing;
use bots or other automated methods to access the content or redirect messages
override any security feature or exclusionary protocol; or
share the content in order to create substitute for Springer Nature products or services or a systematic database of Springer Nature journal
content.
In line with the restriction against commercial use, Springer Nature does not permit the creation of a product or service that creates revenue,
royalties, rent or income from our content or its inclusion as part of a paid for service or for other commercial gain. Springer Nature journal
content cannot be used for inter-library loans and librarians may not upload Springer Nature journal content on a large scale into their, or any
other, institutional repository.
These terms of use are reviewed regularly and may be amended at any time. Springer Nature is not obligated to publish any information or
content on this website and may remove it or features or functionality at our sole discretion, at any time with or without notice. Springer Nature
may revoke this licence to you at any time and remove access to any copies of the Springer Nature journal content which have been saved.
To the fullest extent permitted by law, Springer Nature makes no warranties, representations or guarantees to Users, either express or implied
with respect to the Springer nature journal content and all parties disclaim and waive any implied warranties or warranties imposed by law,
including merchantability or fitness for any particular purpose.
Please note that these rights do not automatically extend to content, data or other material published by Springer Nature that may be licensed
from third parties.
If you would like to use or distribute our Springer Nature journal content to a wider audience or on a regular basis or in any other manner not
expressly permitted by these Terms, please contact Springer Nature at
onlineservice@springernature.com
... Consequently, since future space mission are expected to be long-duration spaceflights and spacecrafts are confined and stressful places with limited facilities, if a sexual intercourse occurs during the mission, physical and psychosocial factors mentioned above may all cause unintended pregnancies despite stringent precautions, frequent tests, and protection methods. In case of a pregnancy, challenges, such as the negative effects of microgravity on pregnancy (Ruden et al., 2018), inadequate -and even a lack of-resources due to an increased nutritional and medical demand of the pregnant member (Schuster and Peck, 2016), and an increased risk of decompression sickness and its detrimental results on fetus (Jennings and Santy, 1990), would all require developing specific health models and protocols. GCR is a kind of ionizing radiation, and it could have the same adverse effects on pregnancy as ionizing radiation. ...
Article
Full-text available
Space missions have revealed certain disincentive factors of this unique environment, such as microgravity, cosmic radiation, etc., as the aerospace industry has made substantial progress in exploring deep space and its impacts on human body. Galactic cosmic radiation (GCR), a form of ionizing radiation, is one of those environmental factors that has potential health implications and, as a result, may limit the duration – and possibly the occurrence – of deep-space missions. High doses of cosmic radiation exposure during spaceflight, particularly during exploration class missions, may have teratogenic effects on a developing fetus, if an unintended pregnancy occurs shortly before or during the flight. This study aimed to discuss whether the cumulative dosage for a pregnant woman during a probable manned mission to Mars may exceed the terrestrial teratogenic radiation limit. A variety of studies, technical documents, and publications that provided flight duration data and the absorbed cosmic radiation dosage equivalents between Earth and Mars were analyzed. A literature-based hypothetical model of a pregnancy simulation over a 6-month spaceflight was also designed to estimate the cumulative absorbed GCR dose. The estimated dose rates ranged from 90 to 324 mSv. Assuming that a pregnant crew member is exposed to this dosage range, the total teratogenic dose equivalent to the embryo/fetus appear to be significantly higher than that of the National Council on Radiation Protection (NCRP)’s and United States Nuclear Regulatory Commission (USNRC)’s recommendations, which state a maximum radiation dose of 5 mSv for the duration of the pregnancy, and thus such an exceeded dose may likely result in teratogenesis. Current protective strategies may not be sufficient to protect the human genome from the detrimental effects of cosmic radiation, and they need be improved for long-term interplanetary travels during human colonization of Mars.
... Sustaining a Mars colony would also require some form of pregnancy and birth in order to sustain the colony. Currently, NASA policies forbid sex in space, and there are no confirmed reports of it happening (Schuster and Peck 2016). Considering astronauts are technically coworkers, this makes sense. ...
Conference Paper
Full-text available
This paper examines private exploration and colonization of space, inspired by the growing interest and advancements in developing space by private industries, notably SpaceX. Marx's theory of primitive accumulation and David Harvey's theory of "spatial fix" provide a framework from which to understand why billionaires are attracted to the business of space. Matters of legality are considered in the regulation of space including treaties, their applications, and the unforeseen gaps in the law left by unanticipated private sector growth. Economic feasibility is discussed through cost and revenue estimates of possible marketable products. Environmental impacts, both on Mars and Earth, are reviewed regarding physical landscape and biological contamination. Finally, it explores the ethics of a developing colony in a stressful environment and seeks to unpack the term colonization in a celestial setting. This paper concludes that bringing capitalist ideals and methods into space is not a solution for problems created by capitalism on Earth. Given the concerns identified, it may well exacerbate them.
... For example, a 2022 report from the United States' Defense Innovation Unit claims a New Space Race with China has begun, and "… seeks to achieve nothing less than the permanent establishment of the first off-planet, human settlement …" [6]. Despite significant technological, biological, legal, geopolitical, and ethical hurdles that still remain [7][8][9][10][11][12][13][14][15], momentum toward space settlement appears to be building. ...
... По време на дълго пътуване до Марс се спекулира,че е вероятно някой от членовете на екипажа да забременее поради интимни контакти породени от стресиращата и изолирана среда. [24] Въпреки всички тези негативни фактори, между Марс и Земята има прилики, които биха направили по-лесно колонизирането на планетата. Те са следните: [25]  Продължителността на деня на Марс е 24 часа, 39 мин. ...
Book
Full-text available
Глава 1 - Влияние на суборбиталните полети върху физиологията на човека Първото човешко творение, което извършва суборбитален полет е ракетата V-2 – „Vergeltungswaffe 2“. При първия си успешен полет през 1942 г., тя прелита 192 km и достига височина 90 km. По време на изпитанията, достига височина 189 km. На 20 февруари 1947 г. е изстреляна от Ню Мексико, САЩ с цял контейнер плодови мушици на височина 109 км над Земята с цел изследване на влиянието на ускорението и космическата радиация върху живи същества. На 05.05.1961 г. американският астронавт Алън Шепърд извършва първия суборбитален полет с ракетата-носител „Редстоун 3“, която извежда космическия кораб „Меркурий 3“ с капсула „Фрийдъм 7“ на балистична траектория. Капсулата достига височина приблизително 186,5 km и каца във водите на Атлантически океан на 486 km от точката на старта. Глава 2 - Влияние на космоса върху човешкото тяло Влизането в Космоса може да има отрицателни ефекти върху човешкото тяло. Значителните неблагоприятни ефекти от дългосрочната безтегловност включват мускулна атрофия, остеопения, забавяне на функциите на сърдечно-съдовата система, намалено производство на червени кръвни клетки, нарушения на баланса, нарушения на зрението и промени в имунната система. Допълнителните симптоми включват преразпределение на течностите (причиняващи външния вид на "лунното лице", типичен за снимки на астронавти, изпитващи безтегловност), загуба на телесна маса, назална конгестия, нарушение на съня и метеоризъм. Глава 3 - Физиологични и други проблеми свързани с пътуване и живот на Марс Тази курсова работа се занимава с проучване на проблемите свързани с живот на Марс, проучването им с цел изграждане на стратегия за живот на планетата и изучаване на факторите влияещи върху човешкото тяло при предполагаем продължителен престой на друга планета. Целта и е да се представи факторите действащи на друга планета, да се изгради план за противодействие на вредните фактори и да се прецени, до каква степен е възможна бъдещата колонизация на тази планета. Хипотетичната колонизация на Марс представлява голям интерес за човечеството и се счита, че ползата от такава колонизация е по-голяма от потенциалните вложени ресурси.
... Besides this ethical issue can put other crew members in risk due to additional requirement of survival resources, intensive care, and attention required for the new born astronaut and mother. The complexity of space environment and microgravity may cause serious health implications to mother and child and can lead to fatal state [132]. It is still uncertain that how far this ethical challenge can be prohibited, but the prime cause for this challenge (i.e. ...
Preprint
Full-text available
Mars is the next frontier for the space explorers to demonstrate the extent of human presence in space beyond low-earth orbit. Both government and private space industries have been fascinated by Mars quest to attempt a crewed expedition to the red planet. The journey to Mars is vastly challenging as it endowed with numerous challenges from the inception of the mission engage to the mission achievement. Therefore, it is substantial to overcome those challenges for a reliable mission. Hence we have studied and emphasized the comprehensive challenges under the categorization of terrestrial, Earth-bound, interplanetary, Mars-bound, and planetary surface challenges. These challenges are suspected to encounter by the astronauts and mission planners throughout the mission timeline. Our research is different from other studies as it reports complete challenges and their implications on the way to human exploration of Mars.
... NASA's policy also forbids sex in space, and there have been no confirmed instances of it happening [79]. ...
Article
Full-text available
Humans and animals adapt to space flight conditions. However, the adaptive changes of fully formed organisms differ radically from the responses of vertebrate embryos, foetuses, and larvae to space flight. Development is associated with active cell proliferation and the formation of organs and systems. The instability of these processes is well known. Over 20 years has passed since the last systematic experiments on vertebrate reproduction and development in space flight. At the same time, programs are being prepared for the exploration of Mars and the Moon, which justifies further investigations into space flight’s impact on vertebrate development. This review focuses on various aspects of reproduction and early development of vertebrates in space flights. The results of various experiments on fishes, amphibians, reptiles, birds and mammals are described. The experiments in which our team took part and ontogeny of the vertebrate nervous and special sensory systems are considered in more detail. Possible causes of morphological changes are also discussed. Research on evolutionarily and taxonomically different models can advance the understanding of reproduction in microgravity. Reptiles, in particular, geckos, due to their special features, can be a promising object of space developmental biology.
... Besides this ethical issue can put other crew members in risk due to additional requirement of survival resources, intensive care, and attention required for the new born astronaut and mother. The complexity of space environment and microgravity may cause serious health implications to mother and child and can lead to fatal state [132]. It is still uncertain that how far this ethical challenge can be prohibited, but the prime cause for this challenge (i.e. ...
Conference Paper
Full-text available
Mars is the next frontier for the space explorers to demonstrate the extent of human presence in space beyond low-earth orbit. Both government and private space industries have been fascinated by Mars quest to attempt a crewed expedition to the red planet. The journey to Mars is vastly challenging as it endowed with numerous challenges from the inception of the mission engage to the mission achievement. Therefore, it is substantial to overcome those challenges for a reliable mission. Hence we have studied and emphasized the comprehensive challenges under the categorization of terrestrial, Earth-bound, interplanetary, Mars-bound, and planetary surface challenges. These challenges are suspected to encounter by the astronauts and mission planners throughout the mission timeline. Our research is different from other studies as it reports complete challenges and their implications on the way to human exploration of Mars.
... Αναφορικά με τη δεύτερη τάση, το διαστημικό περιβάλλον και οι συνθήκες διαβίωσης σε μακροχρόνιες αποστολές στον Άρη αναμένεται να προκαλέσουν σωματικά, ψυχολογικά και κοινωνικά προβλήματα στους αστροναύτες, τα οποία με τη σειρά τους δύνανται να περιορίσουν την ελευθερία και την αυτονομία τους, αφού, εν πρώτοις, μετά την εκτόξευση δεν θα μπορούν να αποχωρήσουν από την αποστολή σε περίπτωση που το θελήσουν [61,64]. Μάλιστα, δεν είναι μόνο οι κίνδυνοι αυτοί καθ' εαυτούς αλλά πολλώ μάλλον οι λύσεις αντιμετώπισής τους που εγείρουν ζητήματα ελευθερίας και αυτονομίας: η έλλειψη των βασικών οικοσυστημικών υπηρεσιών της γήινης βιόσφαιρας δημιουργεί μια μόνιμη εξάρτηση από το σύστημα υποστήριξης ζωής, η στενότητα των πόρων και του διαθέσιμου χώρου θέτει ένα αυστηρό πλαίσιο ελέγχου ζητημάτων αρχής και τέλους ζωής (λ.χ., διαχείριση εγκυμοσύνης ή θεραπεία ασθενούς με περιορισμένα ιατροφαρμακευτικά αναλώσιμα), τα υψηλά επίπεδα κινδύνων για την υγεία και τη ζωή εγείρουν την αναγκαιότητα διαρκούς παρακολούθησης βιοϊατρικών σημάτων και δεικτών, ενώ ορισμένοι ακαδημαϊκοί έχουν ήδη αρχίσει να διερευνούν τις ηθικές προεκτάσεις μιας πιθανής ανάγκης για επιλογή αστροναυτών με βάση ευνοϊκά χαρακτηριστικά της φυσιολογίας τους ή με βάση το φύλο τους, ακόμη και τη βελτίωσή τους σε γενετικό, σωματικό, γνωσιακό, συμπεριφορικό και ηθικό επίπεδο, με τη χρήση φαρμακευτικών, χειρουργικών, τεχνολογικών και γενετικών τεχνικών [45,[65][66][67][68][69][70][71][72][73][74][75][76][77][78]. Ένα τελευταίο αλλά εξίσου σημαντικό ζήτημα είναι και ο κίνδυνος μόλυνσης των αστροναυτών με μικροοργανισμούς που ίσως υπάρχουν στον πλανήτη Άρη. ...
Article
Full-text available
The rise of emergent space initiatives -especially of private ones- has begun to push the boundaries of the space industry, thanks to technological innovations that will soon be able to significantly facilitate the development of previously neglected pioneering fields, such as, for example, space research and exploration, space resources utilization, and human access to space. The invigoration and the forthcoming growth of this new space economy in the aforementioned pioneering fields are expected to bring forward important bioethical issues. The purpose of this paper is to summarize the most important of these issues, after a review of a significant number of relevant publications in the international academic literature. In particular, this paper will present bioethical issues in the field of bioastronautics -especially in light of future missions to Mars- that refer to both life on Earth, i.e. microorganisms, plants, animals and humans, and to potential extraterrestrial life. Given the accelerating rate of developments, the best time to discuss these issues, in order to inform policymaking, is now.
... The search for Earth-like planets has thus far not found concrete evidence of another celestial body conducive to human life (Menou, 2015). Additionally, the present human form cannot survive in space for lengthy periods, and it is not even known if humans can reproduce and give birth to children in outer space (Schuster & Peck, 2016;Setlow, 2003). Given the hostility of space environments to human health, some means of enhancing survivability is a precondition for both long-distance spaceflight and space settlement. ...
Article
The visions of the primary protagonists of the development of outer space diverge in terms of both their motives for and means of extending life into the cosmos. The present article analyses the implications for sustainability associated with the visions of three prominent entities – the National Aeronautics and Space Administration (NASA), the ‘space entrepreneurs’ who lead the private spaceflight industry (such as Elon Musk, Richard Branson, and Jeff Bezos), and transhumanists. This latter category aims to accelerate evolutionary processes to transform humans into a new ‘posthuman’ species which will be imbued with a greatly extended lifespan and other capabilities that enhance survivability in outer space. Due to the inchoate nature of safer and more affordable spaceflight, it is currently unclear which vision of space development will come to fruition. As explored in this article, the proposals advocated by NASA, space entrepreneurs, and transhumanists are associated with divergent implications for sustainability. Trade-off decisions must be made in terms of whether to minimise impacts on Earth, other celestial bodies, or the human form. While it is currently unclear which vision will eventuate, the process of space exploration and settlement is poised to considerably alter current conceptualisations of sustainability.
Chapter
Colonization of Mars: As humans gradually overcome technological challenges of deep space missions, the possibility of exploration and colonization of extraterrestrial outposts is being seriously considered by space agencies and commercial entities alike. But should we do it just because we potentially can? Is such an undoubtedly risky adventure justified from the economical, legal, and ethical points of view? And even if it is, do we have a system of instruments to effectively and fairly manage these aspects of colonisation? In this essay, a rich diversity of current opinions on the pros and cons of Mars colonization voiced by space enthusiasts with backgrounds in space technology, economics, and materials science are examined.
Article
Full-text available
Background: Growing cells in simulated weightlessness condition might be a highly promising new technique to maintain or generate tissue constructs in a scaffold-free manner. There is limited evidence that microgravity condition may affect development of ovarian follicles. The objective of the present study was to investigate the effects of simulated microgravity on the in vitro development of mouse preantral follicles. Methods and results: Ovarian tissue from 14-day-old mice, or preantral follicles mechanically isolated from 14-day-old mouse ovaries were cultured at a simulated microgravity condition generated using a rotating wall vessel apparatus. Follicle survival was assessed quantitatively using H&E staining. Follicle diameter and oocyte diameter were measured under an inverted microscope. Ultrastructure of oocytes was evaluated using transmission electron microscopy. We observed that simulated microgravity compromised follicle survival in vitro, downregulated PCNA and GDF-9 expressions, and caused ultrastructural abnormalities in oocytes. Conclusion: This study showed for the first time that three-dimensional culture condition generated by simulated microgravity is detrimental to the initial stage development of mouse preantral follicles in vitro. The experimental setup provides a model to further investigate the mechanisms involved in the in vitro developmental processes of oocytes/granulosa cells under the microgravity condition.
Article
Full-text available
Healthy immune function depends on precise regulation of lymphocyte activation. During the NASA Apollo and Shuttle eras, multiple spaceflight studies showed depressed lymphocyte activity under microgravity (µg) conditions. Scientists on the ground use two models of simulated µg (sµg), a) the rotating wall vessel (RWV) and b) the random positioning machine (RPM), to study the effects of reduced gravity on cell function before advancing research to the true µg of when spaceflight (SF) opportunities become available on International Space Station (ISS) . The objective of this study is to compare the effects of true µg and sµg on the expression of key early T-cell activation genes in mouse splenocyte from spaceflight and ground animals. For the first time, we compared all three conditions of microgravity SF, RPM and RWV during immune gene activation of Il2, Il2rα, Ifnγ, and Tagap; moreover, we identify two new early T-cell activation genes, Iigp1 and Slamf1. Gene expression for all samples was analyzed using quantitative real-time PCR (qRT-PCR). Our results demonstrate significantly increased gene expression in activated 1g or ground samples with suppression of mouse immune activation in SF, RPM and RWV samples. These findings indicate that sµg models provide an excellent test bed for scientists to baseline and augment experiments for true µg studies in spaceflight. Ultimately, sµg and spaceflight studies in lymphocytes may provide insight into novel regulatory pathways, benefiting both future astronauts and those here on earth suffering from immune disorders. Copyright © 2015, American Journal of Physiology - Regulatory, Integrative and Comparative Physiology.
Article
Full-text available
Objective: To review the current state of knowledge with regards to clinical challenges related to women's health during spaceflight. Methods: Articles were reviewed relevant to "women", "sex," and "gender" in "microgravity," "weightlessness," and "spaceflight" in the English and Russian languages. Results: There were 50 papers identified. Studies have shown that crewmembers suffer from space motion sickness, but gender discrepancies have not been explored. Nearly all women experience orthostatic intolerance in space, which may be due to differences in female cardiovascular response. Immunosuppression in spaceflight results in susceptibility to opportunistic infections, but no studies have investigated gender differences. Finally, radiation exposure and germ cell viability influence the reproductive health of astronauts. Conclusions: With changes in space access offered by commercial space activities, research areas devoted to women's health in microgravity should become one of the priorities for safe space exploratory efforts.
Article
Full-text available
The Mars Science Laboratory spacecraft, containing the Curiosity rover, was launched to Mars on 26 November 2011, and for most of the 253-day, 560-million-kilometer cruise to Mars, the Radiation Assessment Detector made detailed measurements of the energetic particle radiation environment inside the spacecraft. These data provide insights into the radiation hazards that would be associated with a human mission to Mars. We report measurements of the radiation dose, dose equivalent, and linear energy transfer spectra. The dose equivalent for even the shortest round-trip with current propulsion systems and comparable shielding is found to be 0.66 ± 0.12 sievert.
Article
Full-text available
Space travel is a major challenge for human beings. Especially, the mechanisms through which space conditions might alter animal development have been questioned for a long time. The two major physical stress factors that are of relevance in this context are space radiation and weightlessness. While it has been extensively shown that high doses of ionizing radiation induce deleterious effects on embryonic development, so far, little is known about the potential harmful effects of radiation in combination with microgravity on the developing organism. In the present study, we investigated the effects of simulated microgravity on irradiated STO mouse fetal fibroblast cells using a random positioning machine (RPM). Radiation-induced cell cycle changes were not affected when cells were subjected to simulated microgravity for 24 h. Moreover, no morphological differences were observed in irradiated samples exposed to simulated microgravity compared to cells that were exclusively irradiated. However, microgravity simulation significantly decreased the level of apoptosis at all doses as measured by caspase-3 activity and it prevented cells from undergoing radiation-induced size increase up to 1 Gy.
Article
This review is devoted to various aspects of early development under spaceflight conditions. It discusses different possible cell mechanosensors, as well as structural and functional changes in cells, predominantly in non-muscle ones, that are exposed to natural and artificial microgravity. We present the results of different experiments concerning the embryonic development of fish, amphibians, birds, and mammals under microgravity conditions and discuss possible causes of the observed morphological changes.
Conference Paper
Sustaining life beyond Earth on either space stations or other planets will require a clear understanding of how the space environment affects key phases of mammalian reproduction and development. Pregnancy, parturition (birth) and the early development of offspring are complex processes essential for successful reproduction and the proliferation of mammalian species. While no mammal has yet undergone birth within the space environment, studies spanning the gravity continuum from 0- to 2-g are revealing startling insights into how reproduction and development may proceed under gravitational conditions deviating from those typically experienced on Earth. In this report, I review studies of pregnant Norway rats and their offspring flown in microgravity (mug) onboard the NASA Space Shuttle throughout the period corresponding to mid- to late gestation, and analogous studies of pregnant rats exposed to hypergravity (hg) onboard the NASA Ames Research Center 24-ft centrifuge. Studies of postnatal rats flown in space or exposed to centrifugation are reviewed. Although many important questions remain unanswered, the available data suggest that numerous aspects of pregnancy, birth and early mammalian development can proceed under altered gravity conditions. Published by Elsevier Ltd on behalf of COSPAR.
Article
If human history is a guide, exploration missions to Mars will likely be followed by a continuously occupied base and eventual colonization. However, the harsh radiation environment in space will have to be reckoned with. The annual dose in interplanetary space from galactic cosmic radiation (GCR) is about 0.73 Sv during solar minimum and 0.28 Sv during solar maximum. On the surface of Mars, without significant added shielding, the annual dose is reduced to about 0.33 Sv and 0.08 Sv during solar minimum and maximum, respectively. Such high radiation doses are unsustainable for long-duration habitation and will require considerable shielding. Radiation from solar particle events (SPE) can be very intense, but is easier to shield. For perspective, we have grouped radiation health effects into those that may have a threshold (i.e., a dose below which no effect will occur) and those that are not believed to exhibit a threshold. Threshold effects should be prevented if at all possible and non-threshold effects should be reduced to an acceptable level of risk. For adults, the available data suggest effective threshold for serious health effects in the 0.5-Sv range for high dose rate x rays or gamma rays. These data may be useful to estimate the thresholds for GCR protons, which have similar biological effectiveness as gamma rays. However, they cannot be used to estimate the thresholds for high linear energy transfer (LET) heavy ions. That will require new data from radiobiology and a better understanding of how to extrapolate those data to humans. For long-term habitation on Mars, possible in utero exposures must be considered. Serious health effects from radiation exposures in utero can occur at substantially lower doses than in adults. The threshold (or effective threshold) for developmental abnormalities in the fetus during major organogenesis appears to be about 0.1 Sv acute gamma rays. Again, information is not available from high LET radiation for these effects in humans hence estimating a threshold dose for the high-LET component of GCR would have substantial uncertainty at this time. The critical health effect (most radiosensitive) for human colonization of Mars may turn out to be infertility in women resulting from radiation exposure in utero. Although direct human data are not available for this effect, studies in non-human primates have found that oocytes are extremely radiosensitive during gestation, i.e., 50% killed following only 0.07 Sv of chronic tritium beta rays (similar in biological effectiveness to x rays and GCR protons). This would imply that the threshold for early onset of infertility (menopause) could possibly be in the 0.05 Sv range. Protecting the fetus on Mars should be possible using available regolith for shielding material, but it would be difficult to achieve the shielding required to protect the fetus during transit. New technologies in shielding and propulsion would be required for the transit of pregnant women and children. Various countermeasure approaches are discussed as well as the need for non-invasive biomarkers to assess risk susceptibility. Finally, an interesting question is whether Phobos can be used as a shielded base near Mars; there may be substantial natural shielding in Stickney crater (perhaps more than 90% reduction in GCR) due to its position relative to Mars.
Article
The review highlights traditionally important medical conditions for submariners along with the unique consequence of women's health care on the submarine. The information covered includes a review of the history of women in the military followed by a discussion of how women have been integrated into submarines in foreign navies and in space travel. The bulk of the document, then, consists of a literature review that examines gender differences in health care usage as well as in health problems that have traditionally been problematic for submarines including cardiac disease, anemia, asthma, headaches, peptic ulcer disease, orthopedic problems, and psychiatric disease. Gynecological and pregnancy related issues constitute the final area of review.