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Air quality in the clinical embryology laboratory: a mini-review

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Abstract and Figures

The scope of the clinical embryology laboratory has expanded over recent years. It now includes conventional in vitro fertilization (IVF) techniques and complex and time-demanding procedures like blastocyst culture, processing of surgically retrieved sperm, and trophectoderm biopsy for preimplantation genetic testing. These procedures require a stable culture environment in which ambient air quality might play a critical role. The existing data indicate that both particulate matter and chemical pollution adversely affect IVF results, with low levels for better outcomes. As a result, IVF clinics have invested in air cleaning technologies with variable efficiency to remove particulates and volatile organic compounds. However, specific regulatory frameworks mandating air quality control are limited, as are evidence-based guidelines for the best air quality control practices in the embryology laboratory. In this review, we describe the principles and existing solutions for improving air quality and summarize the clinical evidence concerning air quality control in the embryology laboratory. In addition, we discuss the gaps in knowledge that could guide future research to improve clinical outcomes.
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Ther Adv Reprod Health
2021, Vol. 15: 1–11
DOI: 10.1177/
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The number of couples facing infertility has
increased steadily, many of whom will ultimately
need medically assisted reproductive (MAR)
treatment. Global data report over 8 million in
vitro fertilization (IVF) babies born in the last
40 years, and in the UK, IVF babies account for
about 3% of all babies born in 2016.1,2
Furthermore, in the last decades due to the social
and legal equality for same-sex couples, MAR
treatment are increasingly applied for those cou-
ples as well as single women/men and transgender
couples. Consequently, increasing numbers of
homosexual are seeking help to assisted reproduc-
tive technology (ART) to achieve parenthood in
countries where it is allowed.3 IVF is a high-com-
plexity multi-step procedure, which has markedly
evolved over the last decades.4 Human embryo-
genesis involves a coordinated cascade of bio-
chemical and molecular intracellular signaling
events between gametes that results in the devel-
opment of viable embryos capable of implantation
and establishment of viable pregnancies to term.
Indeed, the extended in vitro culture of human
embryos constitutes one of the most challenging
applications of cell culture. This process demands
a more critical growth environment as gametes
and embryos are especially sensitive cells types,
largely unprotected as they lack epithelial surfaces,
immunological defenses, detoxifying mechanisms,
thus being vulnerable to environmental influ-
ences. Studies that have examined environmental
and airborne pathogens have indicated that both
ambient air pollution as well as laboratory air
quality (AQ) may play a significant role on embry-
ogenesis, implantation, and conception of MAR
treatments.5,6 Thus, efforts have been devoted to
optimizing the embryology laboratory environ-
ment to mitigate the possible adverse effect of
ambient air on IVF outcomes. Our review aims to
(1) describe the principles and existing solutions
for improving laboratory air quality, (2) summa-
rize the existing evidence concerning AQ control
in the embryology laboratory, and (3) highlight
Air quality in the clinical embryology
laboratory: a mini-review
Romualdo Sciorio , Erika Rapalini and Sandro C. Esteves
Abstract: The scope of the clinical embryology laboratory has expanded over recent years.
It now includes conventional in vitro fertilization (IVF) techniques and complex and time-
demanding procedures like blastocyst culture, processing of surgically retrieved sperm, and
trophectoderm biopsy for preimplantation genetic testing. These procedures require a stable
culture environment in which ambient air quality might play a critical role. The existing data
indicate that both particulate matter and chemical pollution adversely affect IVF results,
with low levels for better outcomes. As a result, IVF clinics have invested in air cleaning
technologies with variable efficiency to remove particulates and volatile organic compounds.
However, specific regulatory frameworks mandating air quality control are limited, as
are evidence-based guidelines for the best air quality control practices in the embryology
laboratory. In this review, we describe the principles and existing solutions for improving air
quality and summarize the clinical evidence concerning air quality control in the embryology
laboratory. In addition, we discuss the gaps in knowledge that could guide future research to
improve clinical outcomes.
Keywords: air quality (AQ), assisted reproductive technology (ART), embryo culture, in vitro
fertilization (IVF), volatile organic compounds (VOCs)
Received: 26 June 2020; revised manuscript accepted: 7 January 2021.
Correspondence to:
Romualdo Sciorio
Edinburgh Assisted
Conception Programme,
EFREC, Royal Infirmary
of Edinburgh, 51 Little
France Crescent, Old
Dalkeith Road, Edinburgh
EH16 4SA, UK.
Erika Rapalini
Ospedale Versilia,
Centro di Procreazione
medicalmente assistita,
Lido di Camaiore, Italy
Sandro C. Esteves
ANDROFERT, Andrology
and Human Reproduction
Clinic, Campinas, Brazil;
Division of Urology,
Department of Surgery,
University of Campinas
(UNICAMP), Campinas,
Faculty of Health, Aarhus
University, Aarhus,
990684REH0010.1177/2633494121990684Therapeutic Advances in Reproductive HealthR Sciorio, E Rapalini
Therapeutic Advances in Reproductive Health 15
the main gaps in this area of knowledge that could
guide future research and improve ART clinical
What are the threats?
Particulate matter (PM) is a mixture of microscopic
solids and liquid droplets measuring from 1 to 100
microns, in temporary suspension in air. The
embryology laboratory may be served by outdoor
air, whose quality is influenced by many factors,
including construction, vehicle traffic and exhaust,
industrial and commercial emissions, waste man-
agement, and seasonal pollutants, to cite a few.
Microorganisms, like viruses, spores, and bacteria,
measure from < 1 to up 8 microns, and are present
on all inanimate surfaces and in air suspension, cre-
ating potentially sources of contamination in the
embryology laboratory. They can adhere to PM
and contaminate surfaces when the particles set-
tle. Volatile organic compounds (VOCs) are any
organic (carbon-containing) solid or liquid com-
pound that evaporates at room temperature.
They react with indoor ozone and create submi-
cronic particles and harmful by-products, some of
which have toxic properties and are potentially
mutagenic.7 VOCs are generated from a variety of
materials,8 the list is long and includes construction
materials, such as wood furniture,9 polyvinyl chlo-
ride flooring materials,10 adhesives, and paints,11 all
of which release formaldehyde or aldehydes.
Cosmetics like perfumes and aftershaves also
release VOCs due to evaporation of their solvent,
which is typically alcohol-based. Autoclaved mate-
rials release VOCs when packs are opened for use.
Also, laboratory plasticware, which is made from a
variety of plastics like polyethylene, polystyrene,
polycarbonate, polypropylene, and acrylic, release
VOCs. These compounds can also be found in
CO2 gas cylinders, insulation used in air handling
systems, and refrigerant gases.5,8,10 Similarly, clean-
ing products can be a source of VOCs (e.g. vinyl
floor liquid wax and ammonia-based products,
glass cleaners, and aerosols that contain butane or
isobutane as propellants).12 Although low-VOCs
disinfectant, specifically designed to use in IVF
laboratories, have been introduced, many laborato-
ries still use ethanol-based products, which despite
its effect against viruses and bacteria, release VOCs.
Finally, mold growth produce carbon dioxide,
water and VOC. VOCs and other small inorganic
gaseous molecules, including nitrous oxide, sulfur
dioxide, and heavy metals, seem to be detrimental
to embryo development.13,14 Furthermore, VOCs
can harm sperm quality by attaching to the
DNA, causing fragmentation and altering cell
Detecting VOCs in the embryology
In the clinical embryology laboratory, VOC levels
are generally measured using portable direct read-
ing instruments using VOC probes. Short- and
long-term sampling (hours or days) can be utilized
to provide a snapshot or average exposure over
time, respectively. These instruments determine
the total VOC concentration (TVOC), that is, the
total concentration of all VOCs in a defined meas-
uring range, using the photo-ionization detection
(PID) method. The measurements are expressed
in parts per million (ppm) or parts per billion
(ppb), depending on the instrument’s type and
detection limits. Although the PID method has the
advantage of obtaining results immediately, it does
not identify the VOC type or quantify them sepa-
rately. The latter will require active sampling on
TenaxTA® Sorbent, thermal desorption, and gas
chromatography using mass spectrometry, which
provides detailed information about non-polar and
weakly polar VOCs. Aldehydes will need different
measurement methods (eg., 2.4-dinitrophenylhy-
drazine impregnated silica tubes or cartridges with
subsequent solvent desorption, clean-up and liq-
uid chromatographic analysis). Therefore, the
VOC assessment in indoor air is highly dependent
on how this evaluation is performed. All available
methods are selective in what they can measure,
and there is no device capable of measuring all
VOCs. Also, the type of instrument chosen will
determine the sensitivity of the measurements.14
Importantly, the portable devices that measure
TVOCs in ppm might not be able to detect poten-
tially genotoxic, or mutagenic VOCs due to their
low detection limits.16 In the IVF laboratory, it
would be more appropriate to perform VOC meas-
urement with instruments providing readings in
ppb. The results might reflect better the indoor air
quality concerning the potential genotoxicity of the
biochemical interaction between gametes/embryos
and contaminants. In one of the author’s (S.C.E.)
facility, a portable VOC meter in ppb is turned on
during operational hours; 100 ppb is set as the
alarm level above which critical activities such as
incubator openings and gamete/embryo manipula-
tion should be avoided. Threshold values above
R Sciorio, E Rapalini et al. 3
which an adverse effect of VOCs is to be expected
in the context of human cell culture are yet to be
established. Studies have reported that increased
levels of VOCs were related with a statistically sig-
nificant decrease in clinical pregnancy rates, but it
remains mostly unknown the specific thresholds
according to the type of VOC, except for alde-
hydes, which should be kept below the detection
limit of 80–100 ppb.8,17–19 Currently, it has been
generally recommended that IVF laboratories
maintain total VOC levels below 400 to 800 ppb.20
However, a study by Worrilow and colleagues,17
including 8 years of clinical outcomes, and evaluat-
ing the dynamic levels of VOCs and viable and
nonviable particulates within the ambient air of the
IVF laboratory, indicated that VOC levels far
below 100 ppb affected preimplantation embryo-
genesis negatively.
Solutions to improve air quality
The principles of AQ control in the embryology
laboratory involves four main aspects, namely:
(1) air pressure differential, (2) turbulent air, (3)
high-efficiency particulate air (HEPA) filtration,
and (4) VOCs filtration.21 Positive pressure cre-
ates an air pressure differential between adjacent
rooms, thus minimizing retention as both particu-
late matter in air suspension and VOCs are car-
ried away, whereas the newly filtered air dilutes
the remaining particles and VOCs. Air pressuri-
zation also creates turbulent air, which washes
out “dead” air in critical spots like those under
workstations, microscopes, and other equipment.
Similarly, the introduction of particles and VOCs
from the outside air is avoided by the forced air
movement, which uses positive air pressurization
through filters. As mentioned above, microorgan-
isms can adhere to PM; thus, a decrease in the
number of particles in air suspension equates to a
decrease of contamination by pathogens. Removal
of air particles is commonly achieved with the use
of HEPA filters. These filters are designed to
remove 99.97% of particles greater than or equal
to 0.3 microns. However, due to their physical
characteristics, HEPA filters remove not only
particles measuring 0.3 microns or higher (by
sieving or impaction) but also smaller particles
the size of viruses (eg., SARS-CoV-2; ~0.1
microns) by diffusion and interception methods.22
VOCs removal is also critical for improving the
AQ in the embryology laboratory. Typically,
VOCs are removed by sorption filtration (mass
transfer from air to adsorbent) using chemical fil-
ters, typically manufactured as a mesh embedded
with activated carbon, potassium permanganate,
activated alumina, and silica gels.23 The space
between the carbon particles contains delocal-
ized electrons that act as electronic glue, thus
inducing the chemical contaminants to attach to
the carbon.24 Alcohols and ketones, which can-
not be removed by carbons filters, are detoxified
with the use of potassium permanganate.14
Alternatively, VOCs can be removed using ultra-
violet photocatalytic oxidation (UVPCO), gen-
erally combined with the use of carbon filters.25
UVPCO uses the energy of UV lights absorbed by
a semiconductor metal oxide (eg., titanium oxide)
to produce reactive species which adsorb VOCs.
The photo-oxidation of VOCs causes the produc-
tion of CO2, water, and partially oxidized by-
products. Volatile by-products can be released as
secondary pollutants, whereas the filters adsorb
non-volatile by-products. Thus, the real effective-
ness of UVPCO filters is still debatable and not
wholly accepted by the scientific community.26,27
Many air cleaning solutions are commercially
available with variable efficiency to control air
contamination. One option consists of portable
filtration systems, first proposed by Cohen and
colleagues.12 This system employs stand-alone
VOCs filtration units equipped with VOCs and
HEPA filters; some units may also have UVPCO
(Figure 1). Data on their efficacy are minimal,
and it is still premature to make a firm conclusion
on the actual effectiveness of these portable
units.24,25 Another option is the use of centralized
air filtration systems, in which a mix of outside
and recirculated indoor air is pressurized and fil-
tered through a series of dust, VOCs, and termi-
nal HEPA filters (Figure 2). Typically, the
amount of outside air and recirculated air in IVF
laboratory cleanrooms is 20%–25% and 75%–
80%, respectively. This balance is important as
recirculated air is stable and has already been fil-
tered, thus securing the optimal life for the expen-
sive HEPA filters and reducing the running costs
and energy waste. On the other hand, VOC can
accumulate in the indoor environment, and fresh
outside air provides a way of both diluting VOCs
and reducing the risk of cross-contamination
between spaces. The filtered air is distributed to
the embryology laboratory and adjacent rooms
via ducts. The choice of the optimal filtration sys-
tem should be based on a risk management analy-
sis. This analysis should include the design,
Therapeutic Advances in Reproductive Health 15
Figure 1. Illustration depicting a portable four-stage free-standing air filtration system. Reprinted from: Sadir
and colleagues,22 with permission from Taylor & Francis.
Figure 2. Schematic representation of cleanrooms (embryology suite, operating theater, and embryo transfer
suite). Airflow patterns and filtration units are also depicted. The air-handling ventilation unit is located in a
separate room. An external rooftop subunit draws outside air that goes through coarse and activated carbon
prefilters before entering into the main unit. The main ventilation unit pulls prefiltered outside air and the
cleanrooms’ return air through coarse filters, past a 16-unit potassium permanganate-impregnated pelletized
coconut shell-based activated carbon filters and then through fine dust filters. Finally, filtered air enters the
cleanrooms through a set of high-efficiency particulate air (HEPA) filters. Floor- and ceiling-level vents in
the cleanrooms return air to the main ventilation unit to be remixed with the existing air. Differential positive
pressure is maintained between rooms. The embryology laboratory/anteroom is positive to the operating
room, which is positive to both the embryo-transfer room and the dressing room/hallways. Reprinted with
permission from Esteves and Bento.7
R Sciorio, E Rapalini et al. 5
qualification, and operation of the embryology
laboratory.26 Critical aspects to be taken into
account include age and size of the laboratory,
outdoor ambient pollution, whether the facility is
old or new, which affects the VOCs levels, and
the existence of regulatory directives dictating the
air cleanliness to be achieved. While compact
cleaning solutions are less expensive and easy to
implement, they provide less control of air con-
tamination than centralized filtration systems due
to inherent technical limitations concerning their
capability to address the four principles of AQ
control discussed above. The available clinical
data—albeit limited—seem to favor the use of
cleanroom laboratories for AQ.27,28 However, it
remains to be determined if a cleanroom is neces-
sary as no randomized controlled trial has exam-
ined this issue. Also, it is not known if the practice
of using a cleanroom would be more useful in
specific situations, such as laboratories installed
in highly polluted areas. Attention to construc-
tion materials, equipment, furniture, and human
activity is also essential to reduce contamination.
The use of low off-gas materials is preferable, and
laboratory personnel should be trained on the
principles of air quality control, including the
function of airflows and airlocks, hygiene, dress
code, and the use of cleaning agents.5 Equally
important is the use of inline gas filtration systems
as compressed gases (eg., CO2) are known sources
of contaminants, including n-butane, acetalde-
hyde, isopropanol, freon, and benzene.29–33 The
use of modern incubators, properly designed for
the embryology laboratory, with built-in VOC
and HEPA filters (some with UV light) and thus
providing clean air in the embryo culture cham-
bers, may offer additional benefit. These incuba-
tors keep culture conditions, including pH,
temperature, and air quality steady through the
entire period of culture, and therefore, may offer
a valid option for AQC for laboratories that adopt
uninterrupted single step culture media.34
A risk management analysis is paramount to
determine what measures should be implemented
to mitigate the risks associated with chemical and
particulate contamination, as discussed above, as
many activities involving gametes and embryos
are performed in the laboratory environment.
Irrespective of the chosen filtration system, moni-
toring the AQ is also essential. The critical air
cleanliness elements to control periodically
includes (1) no. particles in air suspension, (2) air
pressure differential, (3) air exchanges per hour,
(4) total VOC in air, and (5) microbiological con-
trol. Microbiological contamination is a critical
element to be monitored and must be a part of
the routine quality control process, which is usu-
ally carried out periodically (every 3-6 months)
using air samples, sedimentation plates (e.g.
90 mm plates), and swabbing methods. The num-
ber of colony forming units is measured and the
type of microbial can be determined. Besides,
contamination control measures are of utmost
importance to mitigate the risk of microbial con-
tamination (e.g. use of gloves, masks, and cover-
alls). The heating, ventilation, and air conditioning
(HVAC) is an integral element of the air quality
system. It has to be properly installed, main-
tained, and cleaned. Air ducts, coils, drain pan,
grills, blower motor, air plenum, and air filters are
some of the parts that need to be decontaminated.
During HVAC cleaning, air pressurization should
be placed under negative pressure or vacuum to
prevent the spread of contaminants. The negative
pressure also helps to get rid of dust and fine par-
ticles, as well as loosened contaminants. After
mechanical cleaning, sanitizers are applied to
nonporous surfaces of HVAC systems to control
for microbial contamination. As for filter replace-
ment, it is essential to consider that filter satura-
tion depends on outside air quality and pollution
levels and on the strategies adopted by the embry-
ology laboratory to mitigate the introduction,
generation, and retention of particles and VOCs.
Thus, filter replacement should be guided by the
concurrent analysis of AQ rather than the manu-
facturer’s specifications. A detailed description of
how to perform AQ control in the embryology
laboratory can be found elsewhere.35–37
Summary evidence
In 1997, Cohen and colleagues12 investigated the
effect of chemical contamination on IVF outcomes
in different settings. In this study, a new IVF labo-
ratory was built above one of the busiest streets of
southern Italy, known for its high industrial emis-
sion and stagnant air. At the beginning of the clini-
cal activities, the authors reported a significant
drop in pregnancy rate. After the installation of a
pump to push air through a water-filtered gas bot-
tle before entering the incubator, the pregnancy
results were returned to average values. In another
Therapeutic Advances in Reproductive Health 15
setting, the authors installed solid carbon and
potassium permanganate filters in the IVF labora-
tory to remove adhesive and paint smells and other
pollutants. Sixteen months after the installation,
they found an overall increased implantation rate
from 22% to 36% in a cohort of 1400 patients.
This study suggested that chemical air contamina-
tion might adversely affect in vitro embryo culture
and pregnancy outcomes, albeit the VOC levels
were not precisely evaluated before and after the
introduction of air filtration. The same group in a
subsequent trial investigated the effect of acrolein
on mouse embryo development.14 Acrolein belongs
to the group of aldehydes, and is found in the air,
probably as a result of industrial activity. The com-
pound has also been detected in tobacco smoke.38
The authors found that the mouse embryos
growth was significantly affected after acrolein was
added at different concentrations to the culture
environment.14 The physiological effect was noted
at concentrations in the low ppm range. Although
this is not a typical condition in ART, it could be,
however, speculated that acrolein and other alde-
hydes might be associated with reduced growth of
mammalian embryos.39 Other studies in the late
1990s provided insights into the compounds and
factors that impact AQ. Schimmel and colleagues40
showed that both incubators and compressed
medical gasses are sources of VOCs, as well as ster-
ile Petri dishes, incubators, cleaning supplies,
monitors, microscopes, and even furniture, all of
which contribute to the emission of VOCs.13 A
study published by Nijs and colleagues used the
human sperm survival test to identify potential
reprotoxic products and consumables used in ART
procedures. They analyzed several products cus-
tomarily used in the IVF laboratory, including sur-
gical gloves, ovum pickup needle, type of embryo
transfer catheter, and also sterile Pasteur pipette
and culture Petri dish, and found that 13 of 36
products analyzed were potentially toxic. The
authors speculated that these products might
release chemical compounds toxic to sperm.41
Another critical aspect to consider concerning
chemical contamination to human embryo culture
is the use of mineral oil as a protective overlay dur-
ing human embryo culture. On the one hand, an
oil overlay could be a barrier to water-soluble
VOCs such as ethanol, acetone, and formalde-
hyde. On the other hand, benzene, isobutylene,
and styrene are oil-soluble, highlighting the impor-
tance of controlling VOC sources in the IVF lab.
Added to this, mineral oil is a petroleum-derived
product that can vary widely in quality.
Commercially available oil might contain aromatic
and unsaturated hydrocarbons that are susceptible
to peroxidation and free radical formation,42 par-
ticularly during storage or culture conditions.43
Lately, with the widespread use of the single-step
medium in human in vitro embryo culture, the
mineral oil might be exposed to a longer incuba-
tion time at 37°C up to 7 days, thus increasing the
risk of peroxidation and generation of toxic com-
pounds that could be directly transferred to the
embryo.44 In a 1997 retrospective cohort study
involving infertile couples undergoing IVF, Boone
and colleagues31 observed that the construction of
class 100 cleanroom for air particulates improved
air quality and increased the number of high-qual-
ity embryos available for transfer, ultimately
increasing clinical pregnancy rates. Later in 2013,
Esteves and Bento5 also reported their results after
the construction of a new IVF facility that used a
centralized air ventilation system to supply filtered
air in terms of particles and VOCs to the IVF labo-
ratory, operating room and embryo transfer room.
The new filtration system used forced air move-
ment through a series of pre-filters, 16 beds of acti-
vated carbon mixed with potassium permanganate
and silica, and HEPA filters before the air supplied
the critical areas. The authors reported that during
the study period, few changes other than the envi-
ronmental conditions were made. They measured
air particles and VOC levels before and after the
installation of the new system and noticed a sharp
decrease in both contaminants. In parallel, they
showed an increased live birth rate (35.6% vs
25.8%, P = .02) and decreased miscarriage rate
(20.0% vs 28.7%; P = .04) compared to their
results before the implementation of AQ.5 In 2015,
Munch and colleagues45 assessed the fertilization,
cleavage, blastocyst formation, clinical pregnancy,
and live birth rates in the presence and absence of
carbon filtration. This retrospective cohort
included a total of 524 fresh cycles. The authors
found that fertilization, cleavage, and blastocyst
formation rates were significantly reduced in fresh
IVF when, by mistake, the carbon filters were not
replaced. They also noticed that these metrics
returned to normal ranges when new carbon filters
were installed, thus suggesting that the lack of car-
bon air filtration adversely affected embryo devel-
opment, in particular, around the time of
fertilization, when the oocytes are very sensitive to
air quality changes.45 However, VOC levels were
not reported before and after filters’ replacement,
and it remains speculative if indeed VOC levels
were high in the absence of carbon filtration. In
R Sciorio, E Rapalini et al. 7
another study, Heitmann and colleagues32 assessed
IVF pregnancy outcomes before and after renovat-
ing their IVF facility. The new facility included a
dedicated centralized air filtration system for parti-
cles and VOCs. The authors emphasized that no
changes occurred in the personnel, laboratory
equipment, or protocols during this period.
Overall, the total VOC (819.4 g/m3 vs 32.0 ug/m3)
and aldehyde (13.7 µg/m3 vs 5.2 µg/m3) concentra-
tions in the IVF laboratory decreased after the
installation of the new AQ system. The decrease in
VOC levels were associated with increased rates of
implantation (24.3% vs 32.4%, P < .01), as well as
clinical pregnancy (40.8% vs 50.2%, P = .01) and
live birth (31.8% to 39.3%, P = .03). Table 1 sum-
marizes the relevant clinical studies on AQ and
IVF outcomes published to date. These studies
collectively suggest that laboratory air filtration
might improve both embryonic and pregnancy
outcomes of infertile couples undergoing ART.
However, it is worth noting that the existing stud-
ies are mainly retrospective in nature and lack
proper control groups. Moreover, the implemen-
tation of other relevant changes rather than air
filtration alone could have positively impacted
IVF outcomes. Thus, a cause-effect relationship
remains to be demonstrated in prospective con-
trolled trials.
Gaps in knowledge and future directions
Due to the increasing evidence suggesting an asso-
ciation between laboratory air quality and ART
outcomes, regulatory bodies issued cleanroom
specifications.48,49 While these directives are
intended to safeguard public health in line with the
precautionary principle, they differ in the specifica-
tions on how AQ control has to be handled.5 For
instance, the EU directive focuses on particulate
air only, whereas the Brazilian directive tackles
both particles and VOCs. Along the same lines,
VOC thresholds for embryology laboratories are
lacking, as are specific practice guidelines on good
embryology laboratory practices concerning AQ
control. Nevertheless, a recent document dis-
cussed the relevant aspects concerning AQ control
in the embryology laboratory and provided practi-
cal recommendations based on expert judgment to
guide laboratory design, qualification, and opera-
tion concerning AQ control.20 Nevertheless, level 1
evidence is still lacking to support any recommen-
dation concerning the minimum AQ requirements
for optimal human gamete manipulation and
embryo culture. Indeed, several gaps in knowledge
exist in this area. Notably, it is challenging to per-
form well-designed studies on the effect of air
quality and environmental pollutants on embryo
development. First, there are many chemical com-
pounds partitioned in the air. Second, the VOC
mass transfer from air to water/culture phase of the
cultured cells and embryos is difficult to model.
Nowadays, culture systems are not biphasic due to
the effect of the commonly used oil interphase.
Thus, all gaseous interactions occur through min-
eral oil. Third, the relative solubility of a chemical
compound in oil is described by its oil–water parti-
tion coefficient. Partitioning into mineral oil or
water/culture medium is not the same for different
classes of compounds. Compounds with a high
partition coefficient are hydrophobic (e.g. ben-
zene, styrene) and achieve a much higher concen-
tration in the oil phase than in the aqueous phase
at equilibrium. By contrast, hydrophilic com-
pounds (e.g. ethanol, acrolein) accumulate prefer-
entially into the aqueous phase. Future studies
should focus on the objective determination of the
most relevant chemical contaminants in the IVF
lab, and their thresholds. In this sense, triphasic
models would be essential to study the effects of
chemical contamination on embryo development.
Equally important would be to investigate (e.g.
using well-designed pragmatic clinical trials) the
effectiveness of different air filtration approaches
(eg., cleanroom vs portable filtration systems), and
whether modern “sealed” incubators equipped
with VOC and HEPA filters could compensate the
lack of stringent AQ control. The results of these
studies will be invaluable to elaborate evidence-
based practice guidelines for AQ control in embry-
ology laboratories.
The association between the environment, preim-
plantation toxicology, and successful embryogen-
esis demands a comprehensive evaluation of the
main variables that contribute to air contamination
in the embryology laboratory. Particulate matter
and VOCs are the primary pollutants to be con-
trolled for in the embryology laboratory as they
might adversely affect embryogenesis, implanta-
tion, and conception in ART cycles. Embryology
laboratories that are willing to adopt strict air qual-
ity control should be constructed and used to min-
imize the introduction, retention, and generation
of particles and VOCs, in which temperature,
humidity, and pressure are continuously controlled
and monitored. Attention should also be paid to
Therapeutic Advances in Reproductive Health 15
Table 1. Evidence summarya concerning the impact of air quality control in the embryology laboratory on the outcomes of assisted reproductive technology cycles.
Study Study design Study population Air quality control Outcome
Schimmel and
Descriptive qualitative
None Air sampling and VOCs in human
IVF laboratories
Higher levels of VOC found in CO2 tanks and incubators compared to outside air.
Air filtration using carbon activated and potassium permanganate reduced VOC levels
Hall and colleagues14 Descriptive qualitative
and observational
cohort studies
In vitro mouse
Air sampling and VOCs in human
IVF laboratories and Acrolein
bioassay using mouse embryos
Increased levels of VOC observed in ambient air of human IVF laboratories.
Reduction in aldehyde levels by air filtration using carbon-activated and
In vitro mouse embryo development, implantation, and post-implantation
development inversely correlated with acrolein concentration
Boone and colleagues31 Observational study 275 infertile couples
undergoing IVF;
fresh ET
Centralized system (Class 100
cleanroom) for particle filtration.
Air particles decreased (P < .001) after implementation of centralized air filtration.
Reduction in air particles was associated with an increase in the number of high-
quality embryos (62% vs. 71, P < .001) and CPR per transfer (59% vs. 35%, P = .003).
Khoudja and
Descriptive qualitative
and observational study
1403 infertile
couples undergoing
IVF/ICSI cycles;
fresh ET
Combination of centralized and
portable system to filter particles
and VOCs
VOC levels decreased and overall air quality improved after installation of
centralized VOC air filtration system.
Higher fertilization (83.7% vs. 70.1%, P < .001) blastocyst rate (51.1% vs. 41.7%,
P < .001), IR (34.4% vs. 26.4%, P = .001), and CPR (54.6% vs. 40.6%, P = .001) were
observed after the incorporation of strict air quality control.
Esteves and Bento5Descriptive qualitative
and observational study
2060 ICSI cycles;
fresh ET
Centralized system for particles
(ISO 5 cleanroom) and VOC
filtration (new facility) compared
with portable air filtration system
(old facility)
Higher rates of high-quality embryos and live birth rates (35.6% vs. 25.8%, P = .02),
and lower miscarriage rates (28.7% vs. 20.0%, P = .04) in the new facility than in the
old facility.
Munch and colleagues45 Observational study 524 fresh and 156
cryopreserved IVF/
ICSI cycles
VOC and HEPA air filtration (not
specified if centralized or portable)
Embryonic (cleavage and blastocyst rates rates) and pregnancy (IR, CPR, LBR)
outcomes decreased significantly (P < .05) in fresh cycles carried out in the absence
of VOC air filtration and increased (P < .05) after installation of VOC filters.
Heitmann and
Combination of
descriptive qualitative
and observational study
820 IVF/ICSI cycles;
fresh ET
Centralized system for particle
and VOC filtration (new facility)
compared with portable air
filtration system (old facility)
Lower VOC levels (Total VOC 819.4 μm3 vs. 32 ug/m3, and aldehyde 13.69 ug/m3 vs.
5.2 ug/m3), and higher IR (32.4% vs. 24.3%; P < .01) and LBR (39.3% vs. 31.8%, P = .03)
in the new facility than in the old facility.
Agarwal and
Combination of
descriptive qualitative
and observational study
1036 IVF/ICSI cycles;
fresh ET
Portable air filtration system for
particles and VOCs
Lower VOC levels (P < .0001), higher No. blastocysts (6.3 ± 0.8 vs. 4.5 ± 0.4; P = .04),
and higher IR (42% vs. 31%, P = .001) as well as LBR (31% vs. 23%, P = .009) after
incorporation of air filtration.
CPR: clinical pregnancy rate; ET: embryo transfer; HEPA: high-efficiency particulate air; IR: implantation rate; ISO: international organization for standardization; IVF: in vitro fertilization; ICSI:
intracytoplasmic sperm injection; LBR: live birth rate; VOC: volatile organic compound.
aWe conducted a PubMed search to identify relevant studies published in English until March 3rd, 2020 (start search date not specified). The search terms used were “air quality” AND “in vitro fertilisation” OR
“assisted reproductive technology.” We limited the search to full-text human studies that reported pregnancy outcomes, including cohort studies, case series, cross-sectional studies, and prospective studies.
R Sciorio, E Rapalini et al. 9
other critical issues that might affect indoor air
quality and VOCs emissions, such as laboratory
furniture, wood, equipment, clothing and cosmet-
ics, and sterile plasticware, gloves, incubators and
numbers of embryologist working simultaneously
in the same area. Ideally, a risk management analy-
sis concerning laboratory air quality should take
into consideration not only to reduce but also to
avoid the risks associated with poor air quality con-
ditions.50 Fair evidence indicates that laboratory
air quality is associated with IVF outcome,
although the evidence is not unequivocal.46,47,51
Solid evidence based on prospective trials on the
optimal solution for AQ in ART is still missing.
Most published studies cited earlier are retrospec-
tive and lack proper controls. Some studies were
performed after laboratory renovation; therefore,
additional features might be changed, not only the
air filtration. However, evaluating the impact of
AQ on human early embryo development using
randomized controlled trials are not easy to per-
form due to technical and possible ethical implica-
tions. Furthermore, there are a multitude of factors
affecting ART results, including the characteristics
of treated patients, protocols and procedures, and
environmental pollutants. Finally, we do believe
that the optimal approach of AQ would involve an
embryology laboratory cleanroom, in which a mix-
ture of filtered fresh outside air and recirculated air
for PM and VOC air is supplied, and that includes
both the transfer and operating rooms. Such facil-
ity should be constructed and used in a way to
minimize the introduction, generation, and reten-
tion of particles and VOCs.
Author contributions
R.S., E.R., and S.C.E. contributed to the concep-
tion and designed the manuscript. R.S. and E.R.
wrote the first draft of the manuscript. R.S. and
S.C.E. wrote sections of the manuscript and
revised it for content. All authors contributed to
manuscript revision, read, and approved the sub-
mitted version.
The authors received no financial support for the
research, authorship, and/or publication of this
Conflict of interest statement
The authors declared no potential conflicts of
interest with respect to the research, authorship,
and/or publication of this article.
Romualdo Sciorio
Data availability statement
All data are included in the study.
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... Contrary to common belief, the IVF lab may be less clean in terms of VOCs compared to outside air that is relatively VOC free [44]. Common sources of VOCs are construction materials, wood furniture, paints, adhesives, motor vehicles emissions, and cleaning products [90]. Additionally, they may originate from various sources in the IVF laboratory such as microorganisms, transferred from the overlying oil to the culture medium, tanks of medical gases used for embryo culture, plastic petri dishes, or plastic packages of disposable supplies [91]. ...
... Several studies have documented the detrimental effect of VOCs on human and animal cells in vitro and have linked OS induction with the toxicity of several pollutants [92][93][94][95]. ART outcomes (pregnancy and live birth rates) are indeed linked to air quality of the ART laboratory [90,91]. In humans, environmental pollution has been correlated with high levels of VOCs in human semen, which also corresponded to poorer semen quality in the young males who were inhabiting the area [96]. ...
Full-text available
Oxidative stress (OS) due to an imbalance between reactive oxygen species (ROS) and antioxidants has been established as an important factor that can negatively affect the outcomes of assisted reproductive techniques (ARTs). Excess ROS exert their pathological effects through damage to cellular lipids, organelles, and DNA, alteration of enzymatic function, and apoptosis. ROS can be produced intracellularly, from immature sperm, oocytes, and embryos. Additionally, several external factors may induce high ROS production in the ART setup, including atmospheric oxygen, CO2 incubators, consumables, visible light, temperature, humidity, volatile organic compounds, and culture media additives. Pathological amounts of ROS can also be generated during the cryopreservation-thawing process of gametes or embryos. Generally, these factors can act at any stage during ART, from gamete preparation to embryo development, till the blastocyst stage. In this review, we discuss the in vitro conditions and environmental factors responsible for the induction of OS in an ART setting. In addition, we describe the effects of OS on gametes and embryos. Furthermore, we highlight strategies to ameliorate the impact of OS during the whole human embryo culture period, from gametes to blastocyst stage.
... Multiple layers of protection are typically in place so as to mitigate VOC from the air in IVF laboratories, which can be exposed to high concentrations of embryotoxic VOC. It is well established that IVF facilities should limit VOC, yet thresholds 'remain mostly unknown' for specific VOC (Sciorio et al., 2021). ...
Full-text available
Research Question Can volatile organic compounds (VOCs) be modelled in an in vitro fertilization clinical setting? Design The study is the first known attempt to perform equilibrium modeling of low level airborne VOCs partitioning from the air phase into the oil cover layer into the water based culture media and into/onto the embryo (air-oil-water-embryo). The air phase volatile organic compounds were modelled based on reported VOC concentrations found in modern ART suites, older IVF clinics, hospitals, as well as at 10 ppb and 100 ppb for all compounds. The modeling was performed with 23 documented healthcare specific VOCs. Results The results of the equilibrium partitioning modeling of volatile organic compounds provides fundamental understanding of how airborne VOCs partition from the air phase and negatively influence human IVF outcomes. The results presented herein are based on the theoretical model and the values presented herein have not yet been measured in a laboratory or clinical setting. Conclusions Based on the partitioning model, seven compounds (acrolein, formaldehyde, phenol, toluene, acetaldehyde, ethanol, and isopropanol) should be of great concern to the embryologist and clinician. Acrolein, formaldehyde, phenol, toluene, and acetaldehyde are the VOCs with the most potent cytotoxic factor and the highest toxic VOC level in media. Additionally, ethanol and isopropanol are routinely found in the greatest air-phase concentrations and modelled to have the highest water-based culture concentrations. High air-phase concentrations and toxic levels of VOCs in culture media are likely indicators of poor clinical outcomes. Based on this model, improved air quality in IVF laboratories lowers the chemical burden imparted on embryos, which supports findings of improved IVF outcomes with lowered air-phase VOC concentrations.
... In the past decades, VOCs have attracted worldwide attention and posed a major threat to public health (González-Martín et al., 2021). Researches show that most VOCs such as benzene, toluene, formaldehyde, n-hexane, and ethyl acetate are toxic to human health, and may even cause cancer and death (Sciorio et al., 2021;Davidson et al., 2021;Azhagapillai et al., 2020). Therefore, developing removal technologies for VOCs is an urgent challenge for researchers. ...
Carbon-based adsorbents with a high adsorption capacity and low price have been widely used in the removal of volatile organic compounds (VOCs), but the poor gas selectivity and reusability limit their industrial applications. In this work, disc-like nitrogen-rich porous carbon materials (HAT-Xs) were synthesized to remove typical VOCs via adsorption. By controlling the synthesis temperature from 450 to 1000 °C, the C/N ratio of the HAT-Xs increased from 1.85 to 12.56. The HAT-650 synthesized at 650 °C with the high specific surface area of 305 m2 g-1 exhibits the highest adsorption capacity of 141 mg g-1 for ethyl acetate (which is 3.2 times for that of activated carbon), and 39.4 mg g-1 for n-hexane, 48.6 mg g-1 for toluene. Kinetic studies indicated that the adsorption is physical adsorption and that the interior surface diffusion is the main rate-determining step during the adsorption progress, the interior surface diffusion rate of ethyl acetate on HAT-650 is 1.455 mg g-1 min-0.5. At the same time, the desorption and reuse tests show that HAT-650 has excellent reusability with low desorption and regeneration temperature of 120 °C, and high desorption efficiency of 95.2% and that it could be a promising ethyl acetate adsorbent for industrial applications.
The ART laboratory is a complex system designed to sustain the fertilization, survival, and culture of the preimplantation embryo to the blastocyst stage. ART outcomes depend on numerous factors, among which are the equipment, supplies and culture media used. The number and type of incubators also may affect ART results. While large incubators may be more suitable for media equilibration, bench-top incubators may provide better embryo culture conditions in separate or smaller chambers and may be coupled with time-lapse systems that allow continuous embryo monitoring. Microscopes are essential for observation, assessment, and micromanipulation. Workstations provide a controlled environment for gamete and embryo handling and their quantity should be adjusted according to the number of ART cycles treated in order to provide a steady and efficient workflow. Continuous maintenance, quality control and monitoring of equipment is essential and quality control devices such as the thermometer, and pH-meter are necessary to maintain optimal culture conditions. Tracking, appropriate delivery and storage conditions, and quality control of all consumables is recommended so that the adequate quantity and quality is available for use. Embryo culture media have evolved: preimplantation embryos are cultured either by sequential media or single-step media that can be used for interrupted or uninterrupted culture. There is currently no sufficient evidence that any individual commercially-available culture system is better than others in terms of embryo viability. In this review, we aim to analyse the various parameters that should be taken into account when choosing the essential equipment, consumables and culture media systems that will create optimal culture conditions and provide the most effective patient treatment.
Full-text available
Background: Pregnancy rates after in vitro fertilisation (IVF) treatment continue to improve, while intrauterine insemination (IUI) programmes show no such trend. There is a need to improve success rates with IUI to retain it as a viable option for couples who prefer avoiding IVF as a first line treatment. Objective: To investigate if a modified slow-release insemination (SRI) increases the clinical pregnancy rate (CPR) after intrauterine insemination (IUI) with partner semen. Materials and methods: This was a prospective cohort study in a Belgian tertiary fertility centre. Between July 2011 and December 2018, we studied data from an ongoing prospective cohort study including 989 women undergoing 2565 IUI procedures for unexplained or mild/moderate male infertility. These data were analysed in order to study the importance of different covariates influencing IUI success. Generalised estimating equations (GEEs) were used for statistical analysis. Results of two periods (2011-2015, period 1 and 2016-2018, period 2) were examined and compared. From January 2016 (period 2) onwards, a standardised SRI procedure instead of bolus injection of sperm was applied. The primary outcome parameter was the difference in clinical pregnancy rate (CPR) per cycle between period 1 (bolus IUI) and period 2 (modified SRI). Secondary outcome results included all other parameters significantly influencing CPR after IUI. Results: Following the application of modified SRI the CPR increased significantly, from 9.03% (period 1) to 13.52% (period 2) (p = 0.0016). Other covariates significantly influencing CPR were partner's age, smoking/non-smoking partner, BMI patient, ovarian stimulation protocol and Inseminating Motile Count (after semen processing). Conclusions: Conclusions: The intentional application of modified slow-release of processed semen appears to significantly increase CPRs after IUI with homologous semen. Future studies should investigate whether SRI, patient-centred measures, or a combination of both, are responsible for this improvement.
Full-text available
The optimum oxygen tension for culturing mammalian embryos has been widely debated by the scientific community. While several laboratories have moved to using 5% as the value for oxygen tension, the majority of modern in vitro fertilization (IVF) laboratory programmes still use 20%. Several in vivo studies have shown the oxygen tension measured in the oviduct of mammals fluctuates between 2% and 8% and in cows and primates this values drops to <2% in the uterine milieu. In human IVF, a non-physiological level of 20% oxygen has been used in the past. However, several studies have shown that atmospheric oxygen introduces adverse effects to embryo development, not limited to numerous molecular and cellular physiology events. In addition, low oxygen tension plays a critical role in reducing the high level of detrimental reactive oxygen species within cells, influences embryonic gene expression, helps with embryo metabolism of glucose, and enhances embryo development to the blastocyst stage. Collectively, this improves embryo implantation potential. However, clinical studies have yielded contradictory results. In almost all reports, some level of improvement has been identified in embryo development or implantation, without any observed drawbacks. This review article will examine the recent literature and discusses ongoing efforts to understand the benefits that low oxygen tension can bring to mammal embryo development in vitro .
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Air pollution is a cause of concern for human health. For instance, it is associated with an increased risk for cancer, cardiovascular and respiratory disorders. In vitro and in vivo studies suggested that air pollutants could act as endocrine disruptors, promote oxidative stress and exert genotoxic effect. Whether air pollution affects female infertility is under debate. The aim of the present study was to conduct a systematic review of studies that evaluated the impact of air pollution on female infertility. We systematically searched the MEDLINE (PubMed) and SCOPUS databases to identify all relevant studies published before October 2017. No time or language restrictions were adopted, and queries were limited to human studies. We also hand-searched the reference lists of relevant studies to ensure we did not miss pertinent studies. The risk of bias and quality assessment of the studies identified were performed using the Newcastle-Ottawa Scale. Primary outcomes were conception rate after spontaneous intercourse and live birth rate after in vitro fertilization (IVF) procedures. Secondary outcomes were first trimester miscarriage, stillbirths, infertility, number of oocytes and embryo retrieved. Eleven articles were included in the analysis. We found that in the IVF population, nitrogen dioxide and ozone were associated with a reduced live birth rate while particulate matter of 10 mm was associated with increased miscarriage. Furthermore, in the general population, particulate matter of 2.5 mm and between 2.5 and 10 mm were associated with reduced fecundability, whereas sulfur dioxide, carbon monoxide and nitrogen dioxide might promote miscarriage and stillbirths. The main limitation of our findigns resides in the fact that the desegn of studies included are observational and retrospective. Furthermore, there was a wide heterogenity among studies. Although larger trials are required before drawing definitive conclusions, it seems that air pollution could represent a matter of concern for female infertility. Electronic supplementary material The online version of this article (10.1186/s12958-018-0433-z) contains supplementary material, which is available to authorized users.
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Study question: What are the European trends and developments in ART and IUI in 2014 as compared to previous years? Summary answer: The 18th ESHRE report on ART shows a continuing expansion of both treatment numbers in Europe and more variability in treatment modalities resulting in a rising contribution to the birth rates in most participating countries. What is known already: Since 1997, ART data generated by national registries have been collected, analysed by the European IVF-monitoring (EIM) Consortium and reported in 17 manuscripts published in Human Reproduction. Study design, size, duration: Continuous collection of European data by the EIM for ESHRE. The data for treatments performed in 2014 between 1 January and 31 December in 39 European countries were provided by national registries or on a voluntary basis by clinics or professional societies. Participants/materials, setting, methods: From 39 countries and 1279 institutions offering ART services, a total of 776 556 treatment cycles, involving 146 148 with IVF, 362 285 with ICSI, 192 027 with frozen embryo replacement (FER), 15 894 with PGT, 56 516 with egg donation (ED), 292 with IVM and 3404 with frozen oocyte replacement (FOR) were reported. European data on IUI using husband/partner's semen (IUI-H) and donor semen (IUI-D) were reported from 1364 institutions offering IUI in 26 countries and 21 countries, respectively. A total of 120 789 treatments with IUI-H and 49 163 treatments with IUI-D were included. Main results and the role of chance: In 14 countries (17 in 2013), where all institutions contributed to their respective national registers, a total of 291 235 treatment cycles were performed in a population of ~208 million inhabitants, corresponding to 1925 cycles per million inhabitants (range: 423-2978 per million inhabitants). After treatment with IVF the clinical pregnancy rates (PR) per aspiration and per transfer were marginally higher in 2014 than in 2013, at 29.9 and 35.8% versus 29.6 and 34.5%, respectively. After treatment with ICSI the PR per aspiration and per transfer were also higher than those achieved in 2013 (28.4 and 35.0% versus 27.8 and 32.9%, respectively). After FER with own embryos the PR continued to rise, from 27.0% in 2013 to 27.6% in 2014. After ED a similar trend was observed with PR reaching 50.3% per fresh transfer (49.8% in 2013) and 48.7% for FOR (46.4% in 2013). The delivery rates (DR) after IUI remained stable at 8.5% after IUI-H (8.6% in 2013) and at 11.6% after IUI-D (11.1% in 2013). In IVF and ICSI together, 1, 2, 3 and ≥4 embryos were transferred in 34.9, 54.5, 9.9 and in 0.7% of all treatments, respectively (corresponding to 31.4%, 56.3, 11.5% and 1% in 2013). This evolution in embryo transfer strategy in both IVF and ICSI resulted in a singleton, twin and triplet DR of 82.5, 17.0 and 0.5%, respectively (compared to 82.0, 17.5 and 0.5%, respectively, in 2013). Treatments with FER in 2014 resulted in a twin and triplet DR of 12.4 and 0.3%, respectively (versus 12.5 and 0.3% in 2013). Twin and triplet DR after IUI were 9.5 and 0.3%, respectively, after IUI-H (in 2013:9.5 and 0.6%) and 7.7 and 0.3% after IUI-D (in 2013: 7.5 and 0.3%). Limitation, reasons for caution: The method of data collection and reporting varies among European countries. The EIM receives aggregated data from various countries with variable levels of completeness. Registries from a number of countries have failed to provide adequate data about the number of initiated cycles and deliveries. As long as incomplete data are provided, the results should be interpreted with caution. Wider implications of the findings: The 18th ESHRE report on ART shows a continuing expansion of treatment numbers in Europe. The number of treatments reported, the variability in treatment modalities and the rising contribution to the birth rates in most participating countries point towards the increasing impact of ART on reproduction in Europe. Being the largest data collection on ART, the report gives detailed information about ongoing developments in the field. Study funding/competing interest(s): The study has no external funding and all costs are covered by ESHRE. There are no competing interests.
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This proceedings report presents the outcomes from an international Expert Meeting to establish a consensus on the recommended technical and operational requirements for air quality within modern assisted reproduction technology (ART) laboratories. Topics considered included design and construction of the facility, as well as its heating, ventilation and air conditioning system; control of particulates, micro-organisms (bacteria, fungi and viruses) and volatile organic compounds (VOC) within critical areas; safe cleaning practices; operational practices to optimize air quality while minimizing physicochemical risks to gametes and embryos (temperature control versus air flow); and appropriate infection-control practices that minimize exposure to VOC. More than 50 consensus points were established under the general headings of assessing site suitability, basic design criteria for new construction, and laboratory commissioning and ongoing VOC management. These consensus points should be considered as aspirational benchmarks for existing ART laboratories, and as guidelines for the construction of new ART laboratories.
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Purpose: This study aims to describe the role of implementing good laboratory practices to improve in vitro fertilization (IVF) outcomes which are of great interest for practitioners dealing with infertility. Methods: Certain modifications were introduced in May 2015 in our IVF laboratory like high-efficiency particulate air CODA system, steel furniture instead of wooden, use of new disinfectants like oosafe, and restriction of personnel entry along with avoidance of cosmetics like perfume to improve pregnancy rates. Volatile organic compound (VOC) meter reading was monitored at two time points and five different places in the laboratory to compare the embryonic development parameters before (group A: July 2014-April 2015) and after (group B: July 2015-April 2016) remodeling. Results: The IVF outcomes from 1036 cycles were associated in this study. Reduction in VOC meter readings, enhanced air quality, improvement in blastocyst formation rate, implantation, and clinical pregnancy rate were observed in the laboratory after implementation of new facilities. Results illustrated that the attention must be focused on potential hazards which expose laboratories to elevated VOC levels. Blastocyst formation rate increased around 18%. Implantation rate, clinical pregnancy rate, and live birth rate increased by around 11, 10, and 8%, respectively. Conclusion: In conclusion, with proper engineering and material selection, we have been able to reduce chemical contamination and adverse effects on culture with optimized IVF results. Support: None.
Social and legal equality for same-sex male couples continues to grow in many countries. Consequently, increasing numbers of same-sex male couples are seeking assisted reproductive technology to achieve parenthood. Fertility treatment for same-sex male couples is an undoubtedly complex issue and raises a variety of ethical concerns. Relevant considerations include ethical issues relating to the surrogate and a possible egg donor, the commissioning same-sex couple, the welfare of the child and the fertility clinic itself. This work analyses these arguments in the context of modern fertility services, providing reflection on the evidence present and what it means for clinicians today. Herein, we argue that fertility treatment for same-sex male couples via surrogacy agreements are acceptable, subject to considerations of each individual case, as in all assisted reproductive treatment. It is in the interest of open and equal access to health services that barriers to assisted reproductive technology for same-sex male couples should be minimised where possible.
This monograph, written by the pioneers of IVF and reproductive medicine, celebrates the history, achievements, and medical advancements made over the last 40 years in this rapidly growing field.