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Accuracy of perception of ovulation day in women trying to conceive

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The likelihood of conception is increased if intercourse is timed to coincide with the fertile period (5 days up to ovulation). However, to be effective, this requires good awareness of the day of ovulation. The aim of this study was to examine the accuracy of women's perceived ovulation day, compared with actual fertile days, in a cohort of women trying to conceive. Comparison of women's estimated day of ovulation with their actual ovulation day (determined by detecting luteinising hormone). This was a sample collection study and volunteer women were recruited via online advertising. At recruitment volunteers reported the cycle day they believed they ovulated. They then used a home urine fertility monitor to test their daily fertility status to time intercourse to try and achieve conception, in addition to collecting early morning urine samples for laboratory analysis. The main outcome measure was a comparison of women's estimated day of ovulation with their actual ovulation day, as determined by urine detection of luteinising hormone. Three hundred and thirty women were recruited onto the study and data was available for 102 volunteers who became pregnant. Thirteen women (12.7%) correctly estimated their ovulation day; median difference +2 days, range -10 to +27 days. The most common days for estimation of ovulation were day 14 (35.5%) and day 15 (15.7%). Only 55% of estimated ovulation days fell within the volunteers' fertile window; only 27% on days of peak fertility. Women trying to conceive may benefit from using a prospective method to identify their fertile phase, as a significant proportion could be incorrectly estimating their fertile days. These observations were made on women who were actively looking for knowledge on fertility and considered only cycles where conception occurred, inaccuracy could be greater if a broader population is considered.
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Current Medical Research & Opinion Vol. 28, No. 5, 2012, 1–6
0300-7995 Article FT-0065.R1/681638
doi:10.1185/03007995.2012.681638 All rights reserved: reproduction in whole or part not permitted
Original article
Accuracy of perception of ovulation day
in women trying to conceive
Michael Zinaman
Tufts University School of Medicine, Boston, USA
Sarah Johnson
SPD Swiss Precision Diagnostics Development Co.
Ltd, Bedford, UK
Jayne Ellis
Alere International, Cranfield, UK
William Ledger
University of New South Wales, Royal Hospital for
Women, Sydney, Australia
Address for correspondence:
Sarah Johnson, PhD, Clinical and Medical Affairs
Manager, SPD Development Company Limited,
Priory Business Park, Bedford, MK44 3UP, UK.
Tel.: þ44 (0)1234 835 486;
Fax: þ44 (0)1234 835 006;
Clearblue – Conception – Cycle variability – hCG – LH
surge – Menstrual cycle length – Ovulation –
Pregnancy – Timing of ovulation
Accepted: 27 March 2012; published online: 18 April 2012
Citation: Curr Med Res Opin 2012; 28:1–6
The likelihood of conception is increased if intercourse is timed to coincide with the fertile period (5 days up
to ovulation). However, to be effective, this requires good awareness of the day of ovulation. The aim of this
study was to examine the accuracy of women’s perceived ovulation day, compared with actual fertile days,
in a cohort of women trying to conceive.
Main outcome measures:
Comparison of women’s estimated day of ovulation with their actual ovulation day (determined by detecting
luteinising hormone).
This was a sample collection study and volunteer women were recruited via online advertising. At
recruitment volunteers reported the cycle day they believed they ovulated. They then used a home urine
fertility monitor to test their daily fertility status to time intercourse to try and achieve conception, in addition
to collecting early morning urine samples for laboratory analysis. The main outcome measure was a
comparison of women’s estimated day of ovulation with their actual ovulation day, as determined by
urine detection of luteinising hormone.
Three hundred and thirty women were recruited onto the study and data was available for 102 volunteers
who became pregnant. Thirteen women (12.7%) correctly estimated their ovulation day; median difference
þ2 days, range 10 to þ27 days. The most common days for estimation of ovulation were day 14 (35.5%)
and day 15 (15.7%). Only 55% of estimated ovulation days fell within the volunteers’ fertile window; only
27% on days of peak fertility.
Women trying to conceive may benefit from using a prospective method to identify their fertile phase, as a
significant proportion could be incorrectly estimating their fertile days. These observations were made on
women who were actively looking for knowledge on fertility and considered only cycles where conception
occurred, inaccuracy could be greater if a broader population is considered.
For successful conception, intercourse must occur within a window that spans
five days prior to ovulation and ends on the estimated ovulation day
. If a woman
has an increased awareness of her most fertile time, it will increase the likelihood
of conception
. Therefore timing intercourse to coincide with the fertile
period is a simple method which can maximise the chances of natural concep-
tion. However, to be effective, timed intercourse requires a good awareness of
the day of ovulation
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The use of hormonal monitoring methods to detect the
luteinising hormone (LH) surge in plasma or urine pro-
vides a means to prospectively identify the time of peak
fertility and eliminates the uncertainty of attempting to
pinpoint ovulatory timing via either calendar extrapola-
tions of previous cycle lengths
, or less reliable physio-
logical methods such as basal body temperature and
cervical mucus evaluation
. The LH surge is one of the
most accurate and reliable markers of impending ovula-
tion, with ovulation occurring 24–36 hours after the LH
Women who are trying to conceive may decide to use
any combination of these methods to try to identify their
fertile days, and so begin to develop an awareness of when
these days are in the cycle. However, if a prospective mon-
itoring method is not used, then inter-cycle follicular
phase variability will impact how accurately they are
able to estimate these days. In this study, we examined
the accuracy of perceived day of ovulation in women
attempting to conceive, compared with their actual fertile
days, using urinary hormone monitoring.
Patients and methods
This study was a prospective cohort study, which ran
between July 2008 and February 2009. This study enabled
investigation of women’s knowledge of their menstrual
cycle length characteristics and ovulatory timing by com-
paring their reported cycle length history and estimated
ovulation day with actual cycle lengths and ovulation days,
as determined via urinary hormonal monitoring. Ethical
approval for this study was obtained from the local Ethics
Committee and all study volunteers provided written
informed consent.
Women seeking conception (n¼330) were recruited from
across the UK via an advert on the UK Clearblue website
and had to meet the following inclusion criteria: aged
18–45 years at recruitment; not breast feeding; shortest
cycle 422 days and longest 539 days in the previous 6
months; at least three normal cycles since discontinuation
of hormonal contraception (not taking any medication or
using contraception that could impact their normal men-
strual cycle, e.g. HRT, OCP, Mirena, etc.). Any women
testing positive for pregnancy (Clearblue home pregnancy
test (HPT), SPD Swiss Precision Diagnostics GmbH),
prior to their first menstrual cycle on the trial were
Study protocol
At recruitment, the participants were asked their average
cycle length, their shortest remembered cycle length, their
longest remembered cycle length, and the day of their
cycle on which they thought they ovulated. Participants
were not afforded any assistance when answering the first
three questions and were asked to provide their ‘best esti-
mate’ if they were unsure. They were permitted to answer
‘not known’ to the question concerning their ovulation
date. Data on prior experience of using home ovulation
tests was also collected. These admission results were con-
sidered as the woman’s knowledge of her menstrual cycle.
Volunteers were provided with a home urine fertility
monitor (Clearblue Fertility Monitor, SPD Swiss Precision
Diagnostics GmbH) and urine test sticks that measure
levels of both luteinising hormone (LH) and the oestrogen
metabolite, oestrone-3-glucoronide (E3G), to provide
users with daily information on their fertility status (low,
high and peak fertility), in order for them to appropriately
time intercourse to try and achieve conception.
Volunteers also collected daily early morning urine sam-
ples into bar-coded, childproof containers containing
sodium azide as preservative. Samples were stored by vol-
unteers at 4C and sent to the study centre once the stor-
age container was full (maximum 15 samples). Daily
diaries were also completed for each cycle, recording
menses, monitor usage and medications and were returned
to the study centre on completion of each cycle.
Laboratory analysis
The day of the LH surge was identified in the laboratory
using a home ovulation test (Clearblue Home Ovulation
Test, SPD Swiss Precision Diagnostics GmbH) and was
confirmed by quantitative LH measurements using
AutoDelfia (Perkin Elmer). It was also corroborated
against volunteer diary entries. In addition, pregnancy
was confirmed in the laboratory using HPT and quantita-
tive hCG measurement (AutoDelfia) on the daily urine
samples 15 days following LH surge, for all cycles where
conception occurred.
The average menstrual cycle length reported by volunteers
on admission to the study was 29 days. The average actual
cycle length was calculated for volunteers who failed to
become pregnant in the first cycle (n¼273), and was also
found to be 29 days. However, the range in actual first
cycle length (22–54 days) was considerably greater than
that reported by the non-pregnant volunteers in cycle 1
(24–37 days). One hundred and thirty women conceived
during the study. The pregnancy rate was 17% for cycle 1;
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by cycle 3, 33% of the 330 volunteers had become preg-
nant, and by cycle 6, 42% had become pregnant.
One hundred and two (78.5%) of the pregnant volun-
teers had provided an estimate of their day of ovulation.
Demographic details for these 102 women are presented in
Table 1. The mean age of these women was 30.6 years
(SD 4.63). Seventy-one women (69.6%) had used a
home ovulation test prior to study entry.
Compared with women who had not used home ovula-
tion tests (HOTs) prior to the start of the study, a signif-
icantly higher proportion of HOT users were able to
answer the question: ‘On what day of your cycle do you
think you ovulate?’ (88.8% [95% CI: 80–95%] HOT users
versus 62.0% [95% CI: 47–75%] non-HOT users;
Day 15 (15.7%) and day 14 (35.3%) were the most
common responses for women’s estimated day of ovula-
tion. No women believed they ovulated earlier than day
9 or later than day 25 (Figure 1A). The study population’s
laboratory-calculated actual ovulation days ranged from
day 9 to day 44. Only 19.6% of the women had a calculated
day of ovulation of either day 14 (2.0%) or day 15 (17.6%)
(Figure 1B).
Only 13 women (12.7%) correctly predicted their day
of ovulation, of which 8 (62%) had previously used HOTs,
which is comparable to the number of previous HOT users
recruited to the study (69.6%). A further 39 women
(38.2%) estimated their ovulation day within 1 day
and 57 women (55.9%) estimated their ovulation day
within 2 days. The range of estimated versus actual ovu-
lation days spanned from 10 (i.e. ovulation occurred 10
days earlier than expected) to þ27 (i.e. ovulation occurred
27 days later than expected) (Figure 2) with the median
difference being þ2 days (i.e. the actual ovulation day was
a median of 2 days later than the estimated ovulation day).
We attempted to ascertain whether HOT users were more
accurate in their prediction of day of ovulation than non-
HOT users. Although 51.6% of non-HOT users were more
than 2 days out, either way, with their ovulation-day pre-
diction, compared to 39.4% for the HOT user cohort, the
study numbers were too low to statistically confirm this
When considering whether the women’s estimation of
day of ovulation would have resulted in intercourse on a
day where pregnancy was possible, only 54.9% (Table 2)
would have targeted a day within their fertile window (the
3 days preceding LH surge, day of LH surge and day fol-
lowing the LH surge [calculated day of ovulation]) and
only 26.5% would have targeted their time of peak fertility
(day of LH surge and the following day).
This study, conducted on women seeking to become preg-
nant, found that the majority of women who were able to
estimate their day of ovulation thought that they ovulated
on day 14. The dominance of day 14 may indicate that
women are relying on the text book definitions of a men-
strual cycle, rather than understanding their own actual
cycles. Women who had previously used home ovulation
tests were more likely to provide an answer to the question
On what day of your cycle do you think you ovulate?’ indi-
cating that their use had provided some degree of educa-
tion and awareness regarding their menstrual cycles.
Overall, only 56% of women estimated their day of
ovulation correctly within a margin of 2 days in the
Table 1. Demographic characteristics of the 102 women who conceived
during the study and who predicted their ovulation day.
Characteristic (n¼102 women)
Mean (SD) 30.6 (4.63)
Median 30.5
Quartiles (lower, upper) 28, 34
Minimum, maximum 20, 41
Average cycle length reported at recruitment (days)
Mean (SD) 29.0 (2.50)
Median 28
Quartiles (lower, upper) 28, 30
Minimum, maximum 23, 35
How long have you been trying to conceive? (months)
Mean (SD) 8.1 (6.73)
Median 6
Quartiles (lower, upper) 3, 12
Minimum, maximum 0, 38
No. of women % of women
Age group
18–25 14 14%
26–30 38 37%
31–35 35 34%
36–40 13 13%
41–45 2 2%
Number of previous pregnancies
None 21 21%
1 40 39%
2 20 20%
3 12 12%
Highest qualifications achieved
None 2 2%
GCSE or NVQ 13 13%
HNC/A levels 46 45%
Degree 23 23%
Postgraduate 17 17%
Other 1 1%
Professional 24 24%
Office/administration 37 36%
Other 41 40%
Ever used a home pregnancy test
Yes 99 97%
Ever used a home ovulation test
Yes 71 70%
Age is calculated as at day 1 of cycle 1.
Age group is from subject history form completed at recruitment.
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cycle in which they conceived. When considering whether
this would have enabled timing of intercourse to a fertile
day, only 26.5% would have targeted their most fertile days
and 54.9% would have identified a day where pregnancy
was possible. This was probably due to two important fac-
tors: a lack of awareness of their own menstrual cycle char-
acteristics and their own intra-cycle variability. The
average menstrual cycle length variability is around 7
, with the majority of this variability attributable
to the follicular phase. The only way to correct for this
normal variability is to employ a method that can accu-
rately and prospectively detect the fertile phase within any
given cycle. Such methods include home ovulation tests,
the dual-hormone fertility monitoring device used by the
women in this study (i.e. the Clearblue Fertility Monitor),
or cervical mucus observations. This point is emphasised
by the observation that, ovulation leading to conception
occurred as early as day 9 or as late as day 44, which would
20 Ovulation day earlier than expected
Ovulation day estimated correctly
Ovulation day later than expected
-10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 >=16
Estimated ovulation day - ovulation day reported at recruitment
Percentage of women
Min, Max
2 days later
0, 4 days later
-10, +27 days
Figure 2. The difference between the 102 women’s expected ovulation day and actual ovulation day in the cycle in which they conceived. The actual
ovulation day occurred on the woman’s expected ovulation day in fewer than 13% of instances.
Percentage of women
Laboratory-calculated day of ovulation
>=272513 15 17 19 21 23
cle da
reported as da
of ovulation
911 >=272513 15 17 19 21 23911
(A) (B)
40 40
Median day 14 Median day 16
Quartiles day 14, 16 Quartiles day
30 Min, Max day 9,25 30 Min,
Percentage of women
10 10
Figure 1. A: Range of estimates from the 102 (78%) women who answered the question: On what day of your cycle do you think you ovulate? Fifty-one per
cent of these women believed they ovulated either on day 14 or day 15. No women believed they ovulated earlier than day 9 or later than day 25. B: Range of
‘actual’ ovulation days as calculated via laboratory analysis for the study’s 102 conception cycles. In all cases, the day after the LH surge, as measured by the
Clearblue Ovulation Test (and confirmed by quantitative LH measurements using AutoDelfia (Perkin Elmer), was calculated as the day of ovulation. Ovulation
was found to occur as early as day 9 or as late as day 44.
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be extremely difficult to predict without a prospective
method. It is unlikely that this observation is unusual as
the average and range of menstrual cycle length seen in
these volunteers was consistent with other studies
mean age of these women was 30.6 years (SD 4.63) con-
sistent with the UK average age in pregnancy of 29.5
The cycle length characteristics seen in this study are
strikingly similar to that reported by other authors
However, one interesting observation in this study is the
small number of women whose calculated day of ovulation
(day following LH surge) in their conception cycle was
actually day 14. This is likely to be due to our relatively
small study cohort, although other authors have made sim-
ilar observations. Baird et al. reported that only 10% of
women with regular 28-day menstrual cycles ovulated on
day 14
; furthermore, the most logical conclusion for a
study which found that the human gestational period was
283 (rather than 280) days, is that ovulation on days 15–17
is typical and not delayed
In this study, only 19.6% of women ovulated on day 14
or 15 of their cycle and the actual ovulation day was on
average 2 days later than estimated (Figure 2).
Misjudgement of their actual ovulation day could there-
fore be one reason why the women in this study had been
trying to conceive for an average of 8 months prior to the
study (Table 1). This is considerably longer than observed
in women using fertility awareness methods
. As these
women were able to conceive on this study when using a
fertility monitor, it suggests that incorrect timing may
have been a factor in why these women had previously
failed to conceive. Accurate prediction of ovulation
using home ovulation tests or fertility monitors is thus a
useful aid for women trying to get pregnant and could
shorten the time to conception
Mistiming of intercourse is a primary reason for failure
to conceive
, and although conception-seeking couples are
usually advised to increase their coital frequency, for many
couples, this is neither desirable or achievable
. Use of a
home ovulation test or dual-hormone fertility monitor can
accurately detect the LH surge that immediately precludes
. This enables women to accurately predict
their ovulation date themselves, without expensive labo-
ratory tests or ultrasound examinations
. However, for
some women, these home tests may still be unaffordable.
Cervical mucus monitoring or noting cervical position can
both be used to prospectively identify the fertile period,
although often training is required and these methods can
be of lower accuracy
An important limitation of this study is that it studied
women recruited via an advertisement on a pregnancy/fer-
tility focused website, which is likely to have biased
recruitment towards those seeking more information to
assist with conception. As these women are taking an
active interest in conception it would be expected that
they would be more knowledgeable about their menstrual
cycle than those less actively planning a pregnancy. Also
the analysis only considered cycles in which conception
actually occurred, therefore the findings relate to truly fer-
tile cycles. It is likely that, if non-conceptual cycles were
included, there would be increased variability of menstrual
cycle characteristics, thus women’s perception of their
menstrual cycle characteristics could be less accurate if
these cycles were also considered.
Women trying to conceive may benefit from using a pro-
spective method to identify the fertile phase, as a signifi-
cant proportion could be incorrectly estimating their
fertile days and so incorrectly timing intercourse in order
to conceive.
Declaration of funding
This study was funded by SPD Swiss Precision Diagnostics
Declaration of financial/other relationships
S.J. has disclosed that she is an employee of SPD Development
Company Ltd, UK. J.E. has disclosed that she is a former
employee of SPD Swiss Precision Diagnostics GmbH,
Switzerland. M.Z. and W.L. have disclosed that they have
received honoraria from, and provide ongoing consultancy,
to SPD Development Company Ltd.
CMRO peer reviewers may have received honoraria for their
review work. The peer reviewers on this manuscript have dis-
closed that they have no relevant financial relationships.
The authors would like to thank IMC Healthcare
Communication, funded by SPD Swiss Precision Diagnostics
GmbH, for their assistance in preparing this manuscript.
Previous presentation: ACOG 59th Annual Clinical Meeting,
Washington, USA, 30 April–4 May 2011.
Table 2. Proportion of women (n¼102) whose estimate of day of ovulation
would mean that they would time intercourse to coincide with their fertile
window: peak 2 days (day of LH surge and LH surge þ1), three most fertile
days (day preceding surge, day of LH surge, LH surge þ1), four most fertile
days (2 days before, day of LH surge, LH surge þ1), full fertile window
(3 days preceding surge, day of surge, LH surge þ1).
Number of women Percentage of women
Peak 2 days 27 26.47
Three most fertile days 40 39.22
Four most fertile days 49 48.04
Full fertile window 56 54.90
LH: luteinising hormone.
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... Return of fertility after discontinuation of the LARC methods such as IUD, pills and implants appears to be faster than that after the discontinuation of injectables due to the women's hormonal effects. Duration of contraceptive use, age, parity, women's knowledge on reproductive health (especially of fertile period), occupation, smoking and alcohol consumption have been reported as factors influencing the return of fertility following contraceptive discontinuation [2,4,14,15,18,19]. ...
... The second step provides estimates of survival probabilities (in this case the probabilities of becoming pregnant) after the discontinuation of a LARC. This estimation uses a product-limit formula of the Kaplan-Meier method [19]. In this study, as mentioned above the Kaplan-Meier procedure is used for estimating the probability of women who have conceived at the time t (f) following the discontinuation of reversible contraceptives. ...
Full-text available
Objective The objective of this research is to estimate the probability of pregnancy resumption after discontinuing reversible contraceptives—pills, injectables, implants and IUDs, and to examine the factors associated with the resumption of fertility. Method The study uses pregnancy calendar data from Indonesia Demographic and Health Surveys (IDHS) of 2007, 2012 and 2017. A hazard model survival method is used for estimating the time needed to resume pregnancy since discontinuing reversible contraceptives. Retrospective data on 4,573; 5,183 and 5,989 episodes of reversible contraceptive discontinuation at the three surveys respectively have been analysed. Results This study shows that women regained fecundity within one year of discontinuing IUD, pill, injectables or implants. Women using IUD could resume their pregnancy faster than those using implants, pills and injectables. Over the three IDHS 2007, 2012 and 2017 the age-specific percentages of women becoming pregnant after one year of contraceptive discontinuation vary between 72 and 85 for IUD, 75 and 81 for pills, 72 and 76 for implants and 64 and 67 for injectables, with the percentages being higher among younger women. The analysis further shows that length of contraceptive use, parity, prior sexually transmitted infections, knowledge of fertile period, household wealth status and place of residence have no impact on occurrence of pregnancy after contraceptive discontinuation. Conclusion The analysis disproves a myth that reversible contraceptives make women infertile. Depending on the type of reversible contraceptive used, 65% to 85% of the women were able to conceive after one year of discontinuation.
... Detecting the full fertile window, or the time during which estrogen levels are high and conception is possible, is key for those trying to achieve pregnancy or tracking ovulation for health. However, fewer than 13% of women can correctly identify ovulation [1]. Historically, it was thought that a typical, healthy menstrual cycle lasts 28 days and the fertile days fall between days 10 to 17, based on two assumptions: that a woman ovulates on cycle day (CD) 14 and that she is fertile from the time sperm may survive preceding ovulation through the lifetime of the egg following ovulation (Figure 1a) [2]. ...
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Background and Objectives: To achieve pregnancy, it is highly beneficial to identify the time of ovulation as well as the greater period of fertile days during which sperm may survive leading up to ovulation. Confirming successful ovulation is also critical to accurately diagnose ovulatory disorders. Ovulation predictor kits, fertility monitors, and tracking apps are all available to assist with detecting ovulation, but often fall short. They may not detect the full fertile window, provide accurate or real-time information, or are simply expensive and impractical. Finally, few over-the-counter products provide information to women about their ovarian reserve and future fertility. Therefore, there is a need for an easy, over-the-counter, at-home quantitative hormone monitoring system that assesses ovarian reserve, predicts the entire fertile window, and can screen for ovulatory disorders. Materials and Methods: Proov Complete is a four-in-one at-home multihormone testing system that utilizes lateral flow assay test strips paired with the free Proov Insight App to guide testing of four hormones—FSH, E1G, LH, and PdG—across the woman’s cycle. In a pilot study, 40 women (including 16 with a fertility-related diagnosis or using fertility treatments) used Complete for one cycle. Results: Here, we demonstrate that Proov Complete can accurately and sensitively predict ovarian reserve, detect up to 6 fertile days and confirm if ovulation was successful, in one easy-to-use kit. Ovulation was confirmed in 38 cycles with a detectable PdG rise. An average of 5.3 fertile days (from E1G rise to PdG rise) were detected, with an average of 2.7 days prior to LH surge. Ovulation was confirmed via PdG rise an average of 2.6 days following the LH surge. While 38/40 women had a PdG rise, only 22 had a sustained PdG level above 5 ug/mL throughout the critical implantation window, indicating ovulatory dysfunction in 16 women. Conclusion: Proov Complete can detect the entire fertile window of up to 6 fertile days and confirm ovulation, while also providing information on ovarian reserve and guidance to clinicians and patients.
... [11][12][13] In order for women to be effective at timing intercourse in relationship to the fertile period, a good awareness of their ovulation day is beneficial. 14 Findings from a study on women of reproductive age reported that fertility knowledge, specifically relating to topics such as ovulation, conception, and miscarriage, is limited. 15 Fertility-tracking applications (apps) typically associated with smartphones can be used to track the menstrual cycle. ...
Background: Natural conception requires intercourse to occur during the fertile window of a woman's menstrual cycle. This follow-up study of a randomized controlled trial aimed to determine whether the use of a urine ovulation test system, which tracks elevations in both luteinizing hormone and an estradiol metabolite, increases the likelihood of live births in women trying to conceive. Materials and Methods: In the home-based trial, 844 women aged 18-40 years who were attempting to conceive were randomized 1:1 into the test or control arms. Volunteers participated for up to two full cycles and conducted digital pregnancy tests, collected urine samples, and kept a menstrual diary to determine pregnancy status. In this follow-up, all pregnant volunteers were asked to complete a form on final pregnancy outcome. Results: Overall, 247 (29.3%) of the 844 volunteers reported a pregnancy; final outcome data were available for 198 pregnancies. For cycle one, the live birth rate was 16.4% for the test group and 8.5% for the control group (odds ratio: 2.12; 95% confidence interval [CI]: 1.34-3.35; p = 0.001). For cycles one and two combined, the live birth rate was 24.5% and 17.5% for the test and control groups, respectively (odds ratio: 1.53; 95% CI: 1.07-2.19; p = 0.023). The proportion of miscarriages was not significantly different between both groups and 78% of pregnancies resulted in a live birth. Conclusions: The increased conception rate observed following the use of the Clearblue Connected Ovulation Test System was found to translate into an increased live birth rate. Clinical Trial Registration number: NCT03424590.
... HCG is also known to play myriads of function. It has been shown by [18] that a nexus exist that links HCG with umbilical cord development, suppression of myometrial concentration, angiogenesis, regulation of immune tolerance and the promotion of growth and differentiation of fetal organs. ...
... For couples seeking to conceive, the timing of intercourse is a critical question. Almost 45-50 percent of women do not know their fertile window 1,2 . Calendar based methods cannot accurately predict the fertile window. ...
Fertility testing using urinary hormones has been used to effectively improve the likelihood of pregnancy. To provide fertility scores, the existing home-use systems measure one or two hormones. However, the hormone profiles vary depending on cycle duration, fertility-related disorders, drugs and other treatments. Here, we introduce Inito, a mobile-phone connected reader that is scalable to multiple hormone tests. In this report, we assess the accuracy of the quantitative home-based fertility monitor, the Inito Fertility Monitor (IFM), and suggest using IFM as a device to monitor and analyse female hormone patterns. There were two aspects of the study: i. evaluation of the efficacy of IFM in quantifying urinary Estrone-3-glucuronide (E3G), pregnanediol glucuronide (PdG) and luteinizing hormone (LH), and ii. A retrospective study of patients’ hormone profiles using IFM. We observed that with all three hormones, IFM had an accurate recovery percentage and had a CV of less than 10 percent. Furthermore, in predicting the concentration of urinary hormones, IFM showed a high correlation with ELISA. Using Inito in clinical trials, we report a novel criterion for earlier confirmation of ovulation compared to existing criteria. We also present a novel hormone pattern consistent across most menstrual cycles included in the study. In conclusion, the Inito Fertility Monitor is an effective tool for calculating the urinary concentrations of E3G, PdG and LH and can also be used to provide accurate fertility scores and confirm ovulation. In addition, the sensitivity of IFM facilitates the monitoring of menstrual cycle-related hormone patterns, therefore also making it a great tool for physicians to track the hormones of their patients.
... 5,6 Although the timing of sexual intercourse greatly influences the chances of becoming pregnant, many women seeking to conceive appear to have an inaccurate perception of their ovulatory pattern. 7,8 There is a high degree of intra-and inter-individual variation, both in the length of the menstrual cycle and the relative day of ovulation, which means the fertile window can vary considerably. 9,10 Even for women with an average cycle length of 28 days, ovulation can occur as early as day 11 and as late as day 20 in the cycle. ...
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Background: Women trying to conceive are increasingly using fertility-tracking software applications to time intercourse. This study evaluated the difference in conception rates between women trying to conceive using an application-connected ovulation test system, which measures urinary luteinizing hormone and an estrogen metabolite, versus those trying without using ovulation testing. Materials and Methods: This home-based study involved 844 volunteers aged 18-40 years seeking to conceive. Volunteers randomized to the test arm were required to use the test system for the duration of the study while those randomized to the control arm were instructed not to use ovulation testing. Pregnancy rate differences across one and two cycles between the two groups were examined. Results: Volunteers in the test (n = 382) and control arms (n = 403) had similar baseline demographics. The proportion of women pregnant after one cycle was significantly greater in the test arm (25.4%) compared with the control arm (14.7%; p < 0.001). After two cycles, there continued to be a greater proportion of women pregnant in the test arm compared with the control arm (36.2% vs. 28.6%; p = 0.026). In the test arm, volunteers had intercourse less frequently per cycle compared with those not using ovulation testing (9 [range: 1-60] vs. 10 [range: 1-50]; p = 0.027), but were more likely to target intercourse to a particular part of their cycle compared with those not using ovulation testing (88.5% vs. 57.8%; p < 0.001). Conclusion: Using the test system to time intercourse within the fertile window increases the likelihood of conceiving within two menstrual cycles.
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Study question: What variations underlie the menstrual cycle length and ovulation day of women trying to conceive? Summary answer: Big data from a connected ovulation test revealed the extent of variation in menstrual cycle length and ovulation day in women trying to conceive. What is known already: Timing intercourse to coincide with the fertile period of a woman maximises the chances of conception. The day of ovulation varies on an inter- and intra-individual level. Study design size duration: A total of 32 595 women who had purchased a connected ovulation test system contributed 75 981 cycles for analysis. Day of ovulation was determined from the fertility test results. The connected home ovulation test system enables users to identify their fertile phase. The app benefits users by enabling them to understand their personal fertility information. During each menstrual cycle, users input their perceived cycle length into an accessory application, and data on hormone levels from the tests are uploaded to the application and stored in an anonymised cloud database. This study compared users' perceived cycle characteristics with actual cycle characteristics. The perceived and actual cycle length information was analysed to provide population ranges. Participants/materials setting methods: This study analysed data from the at-home use of a commercially available connected home ovulation test by women across the USA and UK. Main results and the role of chance: Overall, 25.3% of users selected a 28-day cycle as their perceived cycle length; however, only 12.4% of users actually had a 28-day cycle. Most women (87%) had actual menstrual cycle lengths between 23 and 35 days, with a normal distribution centred on day 28, and over half of the users (52%) had cycles that varied by 5 days or more. There was a 10-day spread of observed ovulation days for a 28-day cycle, with the most common day of ovulation being Day 15. Similar variation was observed for all cycle lengths examined. For users who conducted a test on every day requested by the app, a luteinising hormone (LH) surge was detected in 97.9% of cycles. Limitations reasons for caution: Data were from a self-selected population of women who were prepared to purchase a commercially available product to aid conception and so may not fully represent the wider population. No corresponding demographic data were collected with the cycle information. Wider implications of the findings: Using big data has provided more personalised insights into women's fertility; this could enable women trying to conceive to better time intercourse, increasing the likelihood of conception. Study funding/competing interests: The study was funded by SPD Development Company Ltd (Bedford, UK), a fully owned subsidiary of SPD Swiss Precision Diagnostics GmbH (Geneva, Switzerland). I.S., B.G. and S.J. are employees of the SPD Development Company Ltd.
Im Laufe ihres Lebens erlebt die Frau in einem „ovariellen Kontinuum“ das Erwachen und Erlöschen ihrer Fruchtbarkeit, das sich in den verschiedenen Zyklusformen widerspiegelt. Aber auch während der reproduktiven Lebensphase können jederzeit verschiedene Stressoren zu Zyklusstörungen und vorübergehender Beeinträchtigung der Fertilität führen. Es ist jedoch festzuhalten, dass bereits der natürliche und gesunde Zyklus eine große inter- und intraindividuelle Schwankungsbreite aufweist und damit auch Eisprung und fruchtbares Fenster sehr variabel sind, ein Faktum, das angesichts des pilleninduzierten 4-Wochen-Rhythmus bisher nicht im gesellschaftlichen Bewusstsein verankert ist. Der 28-Tage-Zyklus als geforderte Norm für weibliche Gesundheit und Stabilität wird weiterhin in Schulbüchern an jede neue Generation weitergegeben. Das Märchen vom Eisprung am 14. Zyklustag erlebt durch Eisprungrechner und Zyklus-Apps gerade wieder eine unrühmliche und problematische Renaissance. In diesem Kapitel werden die Variabilität des gesunden Zyklus, sowie die verschiedenen Zyklusveränderungen (verlängerte Follikelreifung, Lutealinsuffizienz, Anovulation, Oligo- und Amenorrhöe), ihre hormonellen Ursachen und ihre Auswirkungen auf die NFP beleuchtet.
Halbwissen um die fruchtbare Zeit und die damit verbundene Fokussierung des Sexualverkehrs auf die Zyklusmitte führen nicht selten zu einer Verzögerung des Schwangerschaftseintritts bei Kinderwunsch. Die bisherigen Studienergebnisse rechtfertigen die Integration der Selbstbeobachtung von Zyklussymptomen in das Management des unerfüllten Kinderwunsches als eine nicht invasive, nebenwirkungsfreie und kostengünstige first-line Maßnahme. Dies gilt sowohl bei normal fertilen als auch bei subfertilen Frauen. Oft reicht dabei schon der simple Ratschlag aus, „auf den Zervixschleim zu achten“. Die Zervixschleimbeobachtung bietet ein breiteres fertiles Fenster und ist damit den LH-Testkits überlegen.
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BACKGROUND: The likelihood of spontaneous conception in subsequent cycles is important for a balanced management of infertility. Previous studies on time to pregnancy are mostly retrospective and biased because of exclusion of truly infertile couples. The study aim was to present a non‐parametric estimation of cumulative probabilities of conception (CPC) in natural family planning (NFP) users illustrating an ideal of human fertility potential. METHODS: A total of 346 women was observed who used NFP methods to conceive from their first cycle onwards. The couples practising NFP make optimal use of their fertility potential by timed intercourse. The CPC were estimated for the total group and for couples who finally conceived by calculating Kaplan‐Meier survival rates. RESULTS: A total of 310 pregnancies occurred among the 346 women; the remaining 36 women (10.4%) did not conceive. Estimated CPC for the total group (n = 340 women) at one, three, six and 12 cycle(s) were 38, 68, 81 and 92% respectively. For those who finally conceived (truly fertile couples, n = 304 women), the respective pregnancy rates were 42, 75, 88 and 98% respectively. Although the numbers of couples in both groups were similar, the impact of age on time to conception, as judged by the Wilcoxon test, was less in the truly fertile than in the total group. CONCLUSIONS: Most couples conceive within six cycles with timed intercourse. Thereafter, every second couple is probably either subfertile or infertile. CPC decline with age because heterogeneity in fecundity increases. In the subgroup of truly fertile couples, an age‐dependent decline in CPC is statistically less obvious because of high homogeneity, even with advancing age.
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To define the variability of menstrual cycle length and contribution of follicular and luteal phases to overall cycle variability, and to examine the rise in urinary hCG in early pregnancy. Menstrual cycle study. Urine samples from 101 women (recruited from two south-east counties in the UK) were assayed to determine day of luteinising hormone (LH) surge, lengths of follicular and luteal phases and correlations with total menstrual cycle length. HCG study. Daily urine samples collected from 86 women prior to conception until 43 days post-conception were assayed for hCG and examined versus time since LH surge, determined using fertility test kits. Mean menstrual cycle length was 27.7 +/- 3.4 days, mean follicular phase length was 14.5 +/- 3.4 days and mean luteal phase length was 13.2 +/- 1.9 days. Total cycle lengths varied between and within women. There was a significant correlation (r(2) = 0.70) between follicular phase length and total cycle length; luteal phase length was less variable and showed no association with total cycle length. Concentrations of hCG were significantly similar between women when referenced against the day since LH surge. Three thresholds were determined to indicate time since conception as 1-2 weeks, 2-3 weeks and 3+ weeks. Total cycle length variation is mainly determined by follicular phase variation and predicting menses onset to estimate time of pregnancy testing is unreliable. Evaluating concentrations of hCG relative to LH surge results in consistent increases between women up to 21 days after conception. Therefore, urinary hCG concentration can be used to accurately estimate time since conception.
The intra- and interwoman variation in nine physiologic or biochemical indices of the fertile period has been studied over 58 menstrual cycles from 13 experienced users of the symptothermal method of family planning by periodic abstinence. The time and duration of a possible fertile period have been determined by five methods (symptothermal, cervical mucus, basal body temperature plus calendar calculation, defined changes in the concentration of estrone-3-glucuronide and the ratio of estrone-3-glucuronide to pregnanediol-3 alpha-glucuronide as determined by immunochemical tests on daily samples of early morning urine). The values were compared with a period of probable fertility (day of urinary luteotropin [LH] peak -3 to day of LH peak +2). The duration of the possible fertile period by each method (mean +/- standard deviation) was 13.4 (2.9), 11.9 (2.9), 11.8 (3.3), 9.3 (2.2), and 10.9 (2.3) days, respectively, while the percentage of the probable fertile periods covered entirely by each approach was 98%, 91%, 90%, 83%, and 84%, respectively. The results warrant the initiation of clinical trials to ascertain the practical value of the individual or combined tests for family planning and the management of infertility.
To review and describe various over-the-counter testing products available to the infertility patient, a billion-dollar a year industry that continues to grow. Methodology involved a detailed Medline search of literature, use of online search engines, and focused communications with various manufacturers to determine the usefulness and validity of existing products. Although some home tests have been subjected to scientific scrutiny, others have not. At-home testing represents an opportunity for physicians to involve patients actively in their care. When properly used, these tests also may result in cost savings. However, physicians and consumers must understand the limitations of these tests. Many of the technologies used are innovative and, with proper evaluation and implementation, could serve as valuable adjuncts to medical practice.
Fifty consecutive clients achieved pregnancy using a standardization modification of the Billings ovulation method (the Creighton Model Natural Family Planning System). Of 50 clients followed, 38 (76%) achieved pregnancy in the first cycle of fertility-focused intercourse, 45 of 50 (90%) achieved pregnancy by the third cycle and 49 of 50 achieved pregnancy by the sixth cycle (98%).
We have analysed the duration of pregnancy for singleton births in Sweden during 1976-80 by means of data from the Swedish Birth Registry. Information, which was obtained from special forms with standard questions, include date of first day of last menstrual period (LMP) and whether that date was considered reliable or not. Recording was done prospectively, starting at the first antenatal visit. In 10% of cases the dates were labelled uncertain. Information on LMP and birth dates, parity, age of mother, sex of child, and/or mode of delivery was missing in 5.5% of the singleton cases, leaving 427,581 singleton births for analysis. In cases of reliable menstrual dates, the average duration from LMP to vaginal birth was 282 days (median), 281 days (mean) and 283 days (mode), remaining constant over the years of study. One standard deviation of the mean was approximately 13 days, varying slightly with age and parity. Ten per cent of these women gave birth post term (past 294 days). The duration of cesarean section births became shorter over the years, in spite of little change in cesarean section frequency (9.5% in 1976-7 and 10.9% in 1979-80). Mothers aged 35 and over tended to give birth 2 days earlier than those below 35. Second and subsequent children of mothers below 35 had slightly shorter gestations than first-borns. Boys were born earlier than girls, on average. When LMP was unreliable, the distribution of gestational lengths was wide. We also noted a seasonal rhythmicity in average duration of pregnancy, with consistent shortening in the month of December.
This study was designed to evaluate the accuracy of various methods in predicting and detecting ovulation in 14 spontaneous and 17 clomiphene citrate (CC)-induced cycles. From cycle day 11 all subjects (n = 27) were followed with daily transvaginal ultrasound; rapid measurement of serum luteinizing hormone (LH) and estradiol (E2); determination of urinary LH with First Response (Tambrands Inc., Palmer, MA) and Ovustick (Monoclonal Antibodies, Inc., Mountain View, CA) kits; and recording of basal body temperature (BBT). The results demonstrated that transvaginal ultrasound detected ovulation in all cycles. Mean daily serum LH levels were similar in both groups, and peak values of 40 mIU/ml or greater preceded the day of ovulation in all cycles. Serum E2 peak was significantly greater in CC cycles (961 +/- 96 versus 463 +/- 39 pg/ml) (P less than 0.01) and preceded the LH peak in 97% of the cycles. First Response and Ovustick predicted ovulation in 53.3% and 87.5% of the cycles, respectively (P less than 0.01). BBT nadir predicted the day of ovulation in only 10% of cycles. In conclusion, this study revealed that transvaginal ultrasound is an excellent method for detection of ovulation and that Ovustick is a very useful method for prediction of the day of ovulation.
The timing of sexual intercourse in relation to ovulation strongly influences the chance of conception, although the actual number of fertile days in a woman's menstrual cycle is uncertain. The timing of intercourse may also be associated with the sex of the baby. We recruited 221 healthy women who were planning to become pregnant. At the same time the women stopped using birth-control methods, they began collecting daily urine specimens and keeping daily records of whether they had sexual intercourse. We measured estrogen and progesterone metabolites in urine to estimate the day of ovulation. In a total of 625 menstrual cycles for which the dates of ovulation could be estimated, 192 pregnancies were initiated, as indicated by increases in the urinary concentration of human chorionic gonadotropin around the expected time of implantation. Two thirds (n = 129) ended in live births. Conception occurred only when intercourse took place during a six-day period that ended on the estimated day of ovulation. The probability of conception ranged from 0.10 when intercourse occurred five days before ovulation to 0.33 when it occurred on the day of ovulation itself. There was no evident relation between the age of sperm and the viability of the conceptus, although only 6 percent of the pregnancies could be firmly attributed to sperm that were three or more days old. Cycles producing male and female babies had similar patterns of intercourse in relation to ovulation. Among healthy women trying to conceive, nearly all pregnancies can be attributed to intercourse during a six-day period ending on the day of ovulation. For practical purposes, the timing of sexual intercourse in relation to ovulation has no influence on the sex of the baby.