The length of the fertile window is associated with the chance of spontaneously conceiving an ongoing pregnancy in subfertile couples

Direct-to-consumer fertility testing: utilization and perceived utility among fertility patients and reproductive endocrinologists

RESEARCH QUESTION

What is the utilization of direct-to-consumer fertility tests (DTCFT) among fertility patients? How does the perceived utility of DTCFT differ between patients and reproductive endocrinologists (REI)?

DESIGN

Infertility patients visiting the Duke Fertility Center between December 2020 and December 2021 were sent an electronic invitation to participate in a patient survey. Members of the Society of Reproductive Endocrinology and Infertility were also sent e-mail invitations to participate in the REI survey. DTCFT were defined as tests not ordered by a physician or performed at a physician's office, including calendar methods of ovulation prediction, urinary ovulation prediction kits, basal body temperature (BBT) monitoring, hormone analysis, ovarian reserve testing and semen analysis. Patients and REI were asked how likely they were to recommend a given DTCFT, on a 0-10 Likert scale.

RESULTS

In total, 425 patients (response rate 50.5%) and 178 REI (response rate 21.4%) completed the surveys. Patients reported the utilization of calendar methods of ovulation prediction (83.8%), urinary ovulation prediction (78.8%), BBT monitoring (30.8%), hormone analysis (15.3%), semen analysis (10.1%) and ovarian reserve testing (9.2%). REI rated the utility of all DTCFT significantly lower than patients did (average discordance -4.2, P < 0.001), except for urinary ovulation prediction, which REI gave a significantly higher score (discordance +1.0, P < 0.001). Prior pregnancy was significantly associated with home ovulation prediction utilization among patients (adjusted odds ratio 3.21, 95% confidence interval 1.2-9.83).

CONCLUSIONS

Methods of ovulation prediction are commonly used by fertility patients. Significant discordance exists in the perceived utility of DTCFT between patients and REI. Patient education and guidelines are needed to better inform individuals considering DTCFT.

International Natural Procreative Technology Evaluation and Surveillance of Treatment for Subfertility (iNEST): enrollment and methods

STUDY QUESTION

What is the feasibility of a prospective protocol to follow subfertile couples being treated with natural procreative technology for up to 3 years at multiple clinical sites?

SUMMARY ANSWER

Overall, clinical sites had missing data for about one-third of participants, the proportion of participants responding to follow-up questionnaires during time periods when participant compensation was available (about two-thirds) was double that of time periods when participant compensation was not available (about one-third) and follow-up information was most complete for pregnancies and births (obtained from both clinics and participants).

WHAT IS KNOWN ALREADY

Several retrospective single-clinic studies from Canada, Ireland and the USA, with subfertile couples receiving restorative reproductive medicine, mostly natural procreative technology, have reported adjusted cumulative live birth rates ranging from 29% to 66%, for treatment for up to 2 years, with a mean women’s age of about 35 years.

STUDY DESIGN, SIZE, DURATION

The international Natural Procreative Technology Evaluation and Surveillance of Treatment for Subfertility (iNEST) was designed as a multicenter, prospective cohort study, to enroll subfertile couples seeking treatment for live birth, assess baseline characteristics and follow them up for up to 3 years to report diagnoses, treatments and outcomes of pregnancy and live birth. In addition to obtaining data from medical record abstraction, we sent follow-up questionnaires to participants (both women and men) to obtain information about treatments and pregnancy outcomes, including whether they obtained treatment elsewhere. The study was conducted from 2006 to 2016, with a total of 10 clinics participating for at least some of the study period across four countries (Canada, Poland, UK and USA).

PARTICIPANTS/MATERIALS, SETTING, METHODS

The 834 participants were subfertile couples with the woman’s age 18 years or more, not pregnant and seeking a live birth, with at least one clinic visit. Couples with known absolute infertility were excluded (i.e. bilateral tubal blockage, azoospermia). Most women were trained to use a standardized protocol for daily vulvar observation, description and recording of cervical mucus and vaginal bleeding (the Creighton Model FertilityCare System). Couples received medical and sometimes surgical evaluation and treatments aimed to restore and optimize female and male reproductive function, to facilitate in vivo conception.

MAIN RESULTS AND THE ROLE OF CHANCE

The mean age of women starting treatment was 34.0 years; among those with additional demographic data, 382/478 (80%) had 16 or more years of education, and 199/659 (30%) had a prior live birth. Across 10 clinical sites in four countries (mostly private clinical practices) with family physicians or obstetrician–gynecologists, data about clinic visits were submitted for 60% of participants, and diagnostic data for 77%. For data obtained directly from the couple, 59% of couples had at least one follow-up questionnaire, and the proportion of women and men responding to fill out the follow-up questionnaires was 69% and 67%, respectively, when participant financial compensation was available, compared to 38% and 33% when compensation was not available. Among all couples, 57% had at least one pregnancy and 44% at least one live birth during the follow-up time period, based on data obtained from clinic and/or participant questionnaires. All sites reported on female pelvic surgical procedures, and among all participants, 22% of females underwent a pelvic diagnostic and/or therapeutic procedure, predominantly laparoscopy and hysterosalpingography. Among the 643 (77%) of participants with diagnostic information, ovulation-related disorders were diagnosed in 87%, endometriosis in 31%, nutritional disorders in 47% and abnormalities of semen analysis in 24%. The mean number of diagnoses per couple was 4.7.

LIMITATIONS, REASONS FOR CAUTION

The level of missing data was higher than anticipated, which limits both generalizability and the ability to study different components of treatment and prognosis. Loss to follow-up may also be differential and introduce bias for outcomes. Most of the participating clinicians were not surgeons, which limits the opportunity to study the impact of surgical interventions. Participants were geographically dispersed but relatively homogeneous with regard to socioeconomic status, which may limit the generalizability of current and future findings.

WIDER IMPLICATIONS OF THE FINDINGS

Multicenter studies are key to understanding the outcomes of subfertility treatments beyond IVF or IUI in broader populations, and the association of different prognostic factors with outcomes. We anticipate that the iNEST study will provide insight for clinical and treatment factors associated with outcomes of pregnancy and live birth, with appropriate attention to potential biases (including adjustment for potential confounders, multiple imputation for missing data, sensitivity analysis and inverse probability weighting for potential differential loss to follow-up, and assessments for clinical site heterogeneity). Future studies will need to either have: adequate funding to compensate clinics and participants for robust data collection, including targeted randomized trials; or a scaled-down, registry-based approach with targeted data points, similar to the multiple national and regional ART registries.

STUDY FUNDING/COMPETING INTEREST(S)

Funding for the study came from the International Institute for Restorative Reproductive Medicine, the University of Utah, Department of Family and Preventive Medicine, Health Studies Fund, the Primary Children’s Medical Foundation, the Mary Cross Tippmann Foundation, the Atlas Foundation, the St. Augustine Foundation and the Women’s Reproductive Health Foundation. The authors declare no competing interests.

TRIAL REGISTRATION NUMBER

The iNEST study is registered at clinicaltrials.gov, NCT01363596.

Fertility Awareness-Based Methods for Women's Health and Family Planning

Background

Fertility awareness-based methods (FABMs) educate about reproductive health and enable tracking and interpretation of physical signs, such as cervical fluid secretions and basal body temperature, which reflect the hormonal changes women experience on a cyclical basis during the years of ovarian activity. Some methods measure relevant hormone levels directly. Most FABMs allow women to identify ovulation and track this "vital sign" of the menstrual or female reproductive cycle, through daily observations recorded on cycle charts (paper or electronic).

Applications

Physicians can use the information from FABM charts to guide the diagnosis and management of medical conditions and to support or restore healthy function of the reproductive and endocrine systems, using a restorative reproductive medical (RRM) approach. FABMs can also be used by couples to achieve or avoid pregnancy and may be most effective when taught by a trained instructor.

Challenges

Information about individual FABMs is rarely provided in medical education. Outdated information is widespread both in training programs and in the public sphere. Obtaining accurate information about FABMs is further complicated by the numerous period tracking or fertility apps available, because very few of these apps have evidence to support their effectiveness for identifying the fertile window, for achieving or preventing pregnancy.

Conclusions

This article provides an overview of different types of FABMs with a published evidence base, apps and resources for learning and using FABMs, the role FABMs can play in medical evaluation and management, and the effectiveness of FABMs for family planning, both to achieve or to avoid pregnancy.

Optimizing natural fertility: a committee opinion

This committee opinion provides practitioners with suggestions for optimizing the likelihood of achieving pregnancy in couples or individuals attempting conception who have no evidence of infertility. This document replaces the document of the same name previously published in 2013 (Fertil Steril 2013;100:631-7).

Quantitative Versus Qualitative Estrogen and Luteinizing Hormone Testing for Personal Fertility Monitoring

BACKGROUND

A new fertility monitor is now available that provides quantitative measurement of urinary hormones, but clinical use requires validation against an established fertility monitor that provides only qualitative results.

RESEARCH DESIGN AND METHODS

Two fertility monitors were compared using daily first morning urine samples over 3 cycles of use in 21 women users with experience using a fertility monitor with the Marquette Method of Natural Family Planning.

RESULTS

Women were aged 33.4 ± 5.5 years and had menstrual cycles ranging between 23-41 days. The quantitative Mira Monitor estimates of ovulation were highly correlated with the qualitative ClearBlue Fertility Monitor (CBFM) estimates of ovulation. Both monitors provided an accurate estimate of the fertile window.

CONCLUSIONS

In this preliminary trial, the Mira monitor was shown to be effective at delineating the fertile window and ovulation. We demonstrated the feasibility of applying the Marquette Method algorithm with the use of the Mira monitor. Satisfaction differences between the two monitors did not reach statistical significance. We anticipate that quantitative fertility monitoring will give couples and health care providers new and unprecedented insights into the menstrual cycle and fertility.

Cervical mucus patterns and the fertile window in women without known subfertility: a pooled analysis of three cohorts

STUDY QUESTION

What is the normal range of cervical mucus patterns and number of days with high or moderate day-specific probability of pregnancy (if intercourse occurs on a specific day) based on cervical mucus secretion, in women without known subfertility, and how are these patterns related to parity and age?

SUMMARY ANSWER

The mean days of peak type (estrogenic) mucus per cycle was 6.4, the mean number of potentially fertile days was 12.1; parous versus nulliparous, and younger nulliparous (<30 years) versus older nulliparous women had more days of peak type mucus, and more potentially fertile days in each cycle.

WHAT IS KNOWN ALREADY

The rise in estrogen prior to ovulation supports the secretion of increasing quantity and estrogenic quality of cervical mucus, and the subsequent rise in progesterone after ovulation causes an abrupt decrease in mucus secretion. Cervical mucus secretion on each day correlates highly with the probability of pregnancy if intercourse occurs on that day, and overall cervical mucus quality for the cycle correlates with cycle fecundability. No prior studies have described parity and age jointly in relation to cervical mucus patterns.

STUDY DESIGN, SIZE, DURATION

This study is a secondary data analysis, combining data from three cohorts of women: 'Creighton Model MultiCenter Fecundability Study' (CMFS: retrospective cohort, 1990-1996), 'Time to Pregnancy in Normal Fertility' (TTP: randomized trial, 2003-2006), and 'Creighton Model Effectiveness, Intentions, and Behaviors Assessment' (CEIBA: prospective cohort, 2009-2013). We evaluated cervical mucus patterns and estimated fertile window in 2488 ovulatory cycles of 528 women, followed for up to 1 year.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Participants were US or Canadian women age 18-40 years, not pregnant, and without any known subfertility. Women were trained to use a standardized protocol (the Creighton Model) for daily vulvar observation, description, and recording of cervical mucus. The mucus peak day (the last day of estrogenic quality mucus) was used as the estimated day of ovulation. We conducted dichotomous stratified analyses for cervical mucus patterns by age, parity, race, recent oral contraceptive use (within 60 days), partial breast feeding, alcohol, and smoking. Focusing on the clinical characteristics most correlated to cervical mucus patterns, linear mixed models were used to assess continuous cervical mucus parameters and generalized linear models using Poisson regression with robust variance were used to assess dichotomous outcomes, stratifying by women's parity and age, while adjusting for recent oral contraceptive use and breast feeding.

MAIN RESULTS AND THE ROLE OF CHANCE

The majority of women were <30 years of age (75.4%) (median 27; IQR 24-29), non-Hispanic white (88.1%), with high socioeconomic indicators, and nulliparous (70.8%). The mean (SD) days of estrogenic (peak type) mucus per cycle (a conservative indicator of the fertile window) was 6.4 (4.2) days (median 6; IQR 4-8). The mean (SD) number of any potentially fertile days (a broader clinical indicator of the fertile window) was 12.1 (5.4) days (median 11; IQR 9-14). Taking into account recent oral contraceptive use and breastfeeding, nulliparous women age ≥30 years compared to nulliparous women age <30 years had fewer mean days of peak type mucus per cycle (5.3 versus 6.4 days, P = 0.02), and fewer potentially fertile days (11.8 versus 13.9 days, P < 0.01). Compared to nulliparous women age <30 years, the likelihood of cycles with peak type mucus ≤2 days, potentially fertile days ≤9, and cervical mucus cycle score (for estrogenic quality of mucus) ≤5.0 were significantly higher among nulliparous women age ≥30 years, 1.90 (95% confidence interval (CI) 1.18, 3.06); 1.46 (95% CI 1.12, 1.91); and 1.45 (95% CI 1.03, 2.05), respectively. Between parous women, there was little difference in mucus parameters by age. Thresholds set a priori for within-woman variability of cervical mucus parameters by cycle were examined as follows: most minus fewest days of peak type mucus >3 days (exceeded by 72% of women), most minus fewest days of non-peak type mucus >4 days (exceeded by 54% of women), greatest minus least cervical mucus cycle score >4.0 (exceeded by 73% of women), and most minus fewest potentially fertile days >8 days (found in 50% of women). Race did not have any association with cervical mucus parameters. Recent oral contraceptive use was associated with reduced cervical mucus cycle score and partial breast feeding was associated with a higher number of days of mucus (both peak type and non-peak type), consistent with prior research. Among the women for whom data were available (CEIBA and TTP), alcohol and tobacco use had minimal impact on cervical mucus parameters.

LIMITATIONS, REASONS FOR CAUTION

We did not have data on some factors that may impact ovulation, hormone levels, and mucus secretion, such as physical activity and body mass index. We cannot exclude the possibility that some women had unknown subfertility or undiagnosed gynecologic disorders. Only 27 women were age 35 or older. Our study participants were geographically dispersed but relatively homogeneous with regard to race, ethnicity, income, and educational level, which may limit the generalizability of the findings.

WIDER IMPLICATIONS OF THE FINDINGS

Patterns of cervical mucus secretion observed by women are an indicator of fecundity and the fertile window that are consistent with the known associations of age and parity with fecundity. The number of potentially fertile days (12 days) is likely greater than commonly assumed, while the number of days of highly estrogenic mucus (and higher probability of pregnancy) correlates with prior identifications of the fertile window (6 days). There may be substantial variability in fecundability between cycles for the same woman. Future work can use cervical mucus secretion as an indicator of fecundity and should investigate the distribution of similar cycle parameters in women with various reproductive or gynecologic pathologies.

STUDY FUNDING/COMPETING INTEREST(S)

Funding for the three cohorts analyzed was provided by the Robert Wood Johnson Foundation (CMFS), the Eunice Kennedy Shriver National Institute of Child Health and Human Development (TTP), and the Office of Family Planning, Office of Population Affairs, Health and Human Services (CEIBA). The authors declare that they have no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Period tracker applications: What menstrual cycle information are they giving women?

BACKGROUND

Period tracking applications (apps) allow women to track their menstrual cycles and receive a prediction for their period dates. The majority of apps also provide predictions of ovulation day and the fertile window. Research indicates apps are basing predictions on assuming women undergo a textbook 28-day cycle with ovulation occurring on day 14 and a fertile window between days 10 and 16.

OBJECTIVE

To determine how the information period tracker apps give women on their period dates, ovulation day and fertile window compares to expected results from big data.

METHODS

Five women's profiles for 6 menstrual cycles were created and entered into 10 apps. Cycle length and ovulation day for the sixth cycle were Woman 1-Constant 28 day cycle length, ovulation day 16; Woman 2-Average 23 day cycle length, ovulation day 13; Woman 3-Average 28 day cycle length, ovulation day 17; Woman 4-Average 33 day cycle length, ovulation day 20; and Woman 5-Irregular, average 31 day cycle length, ovulation day 14.

RESULTS

The 10 period tracker apps examined gave conflicting information on period dates, ovulation day and the fertile window. For cycle length, the apps all predicted woman 1's cycles correctly but for women 2-5, the apps predicted 0 to 8 days shorter or longer than expected. For day of ovulation, for women 1-4, of the 36 predictions, 3 (8%) were exactly correct, 9 predicted 1 day too early (25%) and 67% of predictions were 2-9 days early. For woman 5, most of the apps predicted a later day of ovulation.

CONCLUSION

Period tracker apps should ensure they only give women accurate information, especially for the day of ovulation and the fertile window which can only be predicted if using a marker of ovulation, such as basal body temperature, ovulation sticks or cervical mucus.

Predictive Factors of Conception and the Cumulative Pregnancy Rate in Subfertile Couples Undergoing Timed Intercourse With Ultrasound

The aim of this study was to determine predictive factors for pregnancy and assess the cumulative pregnancy rate (CPR) and live birth rate (CLBR) in subfertile couples undergoing timed intercourse (TI) using ultrasound. This retrospective cohort study included 285 women (854 cycles) who started TI with ultrasound between January 2017 and October 2019. The overall clinical pregnancy rate was 28.1% (80/285) per couple and 9.4% (80/854) per cycle. Pregnant women had a higher body mass index (BMI), higher percentage of irregular menstrual cycles, a shorter duration of subfertility, lower serum follicle-stimulating hormone levels, and higher anti-Müllerian hormone levels than non-pregnant women. A longer duration of subfertility (≥24 months vs. <12 months; odds ratio: 0.193; 95% confidence interval: 0.043-0.859) and endometriosis (vs. ovulatory factors; odds ratio: 0.282; 95% confidence interval: 0.106-0.746) as causes of subfertility were unfavorable factors that independently affected clinical pregnancy. In subgroup analysis, old age ≥ 35 years [vs. < 35 years; odds ratio: 0.279; 95% confidence interval: 0.083-0.938), a longer duration of infertility ≥24 months (vs. <24 months; odds ratio: 0.182; 95% confidence interval: 0.036-0.913) and a higher BMI ≥ 25 kg/m²(vs. >25 kg/m²; odds ratio: 3.202; 95% confidence interval: 1.020-10.046) in couples with ovulatory factor and a longer duration of infertility ≥24 months (vs. <24 months; odds ratio: 0.185; 95% confidence interval: 0.042-0.819) in couples with non-ovulatory factors were significant independent predictive factors for pregnancy. No significant differences were found in the cycle characteristics between pregnant and non-pregnant women. The CPR substantially increased during the first three cycles and significantly increased until the sixth cycle. No significant increase was observed in the CPR after the sixth cycle. The CLBRs substantially increased during the first three cycles and significantly increased until the fourth cycle. No significant increase was observed in the CLBRs after the fifth cycle. When comparing CPRs and CLBRs according to subfertile causes, CRPs was significantly different and CLBRs was different with borderline significance. Our findings may indicate that women with a longer duration of subfertility or subfertility due to endometriosis have poor outcomes during TI with ultrasound. Women who failed to achieve conception by the fourth or fifth cycle of TI with ultrasound may be encouraged to consider advancing to the next treatment strategy.

Ultradian rhythms in heart rate variability and distal body temperature anticipate onset of the luteinizing hormone surge

The menstrual cycle is characterized by predictable patterns of physiological change across timescales. Although patterns of reproductive hormones across the menstrual cycle, particularly ultradian rhythms, are well described, monitoring these measures repeatedly to predict the preovulatory luteinizing hormone (LH) surge is not practical. In the present study, we explored whether non-invasive measures coupled to the reproductive system: high frequency distal body temperature (DBT), sleeping heart rate (HR), sleeping heart rate variability (HRV), and sleep timing, could be used to anticipate the preovulatory LH surge in women. To test this possibility, we used signal processing to examine these measures in 45 premenopausal and 10 perimenopausal cycles alongside dates of supra-surge threshold LH and menstruation. Additionally, urinary estradiol and progesterone metabolites were measured daily surrounding the LH surge in 20 cycles. Wavelet analysis revealed a consistent pattern of DBT and HRV ultradian rhythm (2-5 h) power that uniquely enabled anticipation of the LH surge at least 2 days prior to its onset in 100% of individuals. Together, the present findings reveal fluctuations in distal body temperature and heart rate variability that consistently anticipate the LH surge, suggesting that automated ultradian rhythm monitoring may provide a novel and convenient method for non-invasive fertility assessment.

Fecundability in relation to use of mobile computing apps to track the menstrual cycle

STUDY QUESTION

To what extent does the use of mobile computing apps to track the menstrual cycle and the fertile window influence fecundability among women trying to conceive?

SUMMARY ANSWER

After adjusting for potential confounders, use of any of several different apps was associated with increased fecundability ranging from 12% to 20% per cycle of attempt.

WHAT IS KNOWN ALREADY

Many women are using mobile computing apps to track their menstrual cycle and the fertile window, including while trying to conceive.

STUDY DESIGN, SIZE, DURATION

The Pregnancy Study Online (PRESTO) is a North American prospective internet-based cohort of women who are aged 21-45 years, trying to conceive and not using contraception or fertility treatment at baseline.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We restricted the analysis to 8363 women trying to conceive for no more than 6 months at baseline; the women were recruited from June 2013 through May 2019. Women completed questionnaires at baseline and every 2 months for up to 1 year. The main outcome was fecundability, i.e. the per-cycle probability of conception, which we assessed using self-reported data on time to pregnancy (confirmed by positive home pregnancy test) in menstrual cycles. On the baseline and follow-up questionnaires, women reported whether they used mobile computing apps to track their menstrual cycles ('cycle apps') and, if so, which one(s). We estimated fecundability ratios (FRs) for the use of cycle apps, adjusted for female age, race/ethnicity, prior pregnancy, BMI, income, current smoking, education, partner education, caffeine intake, use of hormonal contraceptives as the last method of contraception, hours of sleep per night, cycle regularity, use of prenatal supplements, marital status, intercourse frequency and history of subfertility. We also examined the impact of concurrent use of fertility indicators: basal body temperature, cervical fluid, cervix position and/or urine LH.

MAIN RESULTS AND THE ROLE OF CHANCE

Among 8363 women, 6077 (72.7%) were using one or more cycle apps at baseline. A total of 122 separate apps were reported by women. We designated five of these apps before analysis as more likely to be effective (Clue, Fertility Friend, Glow, Kindara, Ovia; hereafter referred to as 'selected apps'). The use of any app at baseline was associated with 20% increased fecundability, with little difference between selected apps versus other apps (selected apps FR (95% CI): 1.20 (1.13, 1.28); all other apps 1.21 (1.13, 1.30)). In time-varying analyses, cycle app use was associated with 12-15% increased fecundability (selected apps FR (95% CI): 1.12 (1.04, 1.21); all other apps 1.15 (1.07, 1.24)). When apps were used at baseline with one or more fertility indicators, there was higher fecundability than without fertility indicators (selected apps with indicators FR (95% CI): 1.23 (1.14, 1.34) versus without indicators 1.17 (1.05, 1.30); other apps with indicators 1.30 (1.19, 1.43) versus without indicators 1.16 (1.06, 1.27)). In time-varying analyses, results were similar when stratified by time trying at study entry (<3 vs. 3-6 cycles) or cycle regularity. For use of the selected apps, we observed higher fecundability among women with a history of subfertility: FR 1.33 (1.05-1.67).

LIMITATIONS, REASONS FOR CAUTION

Neither regularity nor intensity of app use was ascertained. The prospective time-varying assessment of app use was based on questionnaires completed every 2 months, which would not capture more frequent changes. Intercourse frequency was also reported retrospectively and we do not have data on timing of intercourse relative to the fertile window. Although we controlled for a wide range of covariates, we cannot exclude the possibility of residual confounding (e.g. choosing to use an app in this observational study may be a marker for unmeasured health habits promoting fecundability). Half of the women in the study received a free premium subscription for one of the apps (Fertility Friend), which may have increased the overall prevalence of app use in the time-varying analyses, but would not affect app use at baseline. Most women in the study were college educated, which may limit application of results to other populations.

WIDER IMPLICATIONS OF THE FINDINGS

Use of a cycle app, especially in combination with observation of one or more fertility indicators (basal body temperature, cervical fluid, cervix position and/or urine LH), may increase fecundability (per-cycle pregnancy probability) by about 12-20% for couples trying to conceive. We did not find consistent evidence of improved fecundability resulting from use of one specific app over another.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported by grants, R21HD072326 and R01HD086742, from the Eunice Kennedy Shriver National Institute of Child Health and Human Development, USA. In the last 3 years, Dr L.A.W. has served as a fibroid consultant for AbbVie.com. Dr L.A.W. has also received in-kind donations from Sandstone Diagnostics, Swiss Precision Diagnostics, FertilityFriend.com and Kindara.com for primary data collection and participant incentives in the PRESTO cohort. Dr J.B.S. reports personal fees from Swiss Precision Diagnostics, outside the submitted work. The remaining authors have nothing to declare.

TRIAL REGISTRATION NUMBER

N/A.

Real-life insights on menstrual cycles and ovulation using big data

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.

Fecundability in relation to use of fertility awareness indicators in a North American preconception cohort study

OBJECTIVE

To quantify the frequency of use of selected fertility awareness indicators and to assess their influence on fecundability.

DESIGN

Web-based prospective cohort study.

SETTING

Not applicable.

PATIENT(S)

Female pregnancy planners, aged 21-45 years, attempting conception for ≤6 cycles at study entry.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

We ascertained time to pregnancy, in menstrual cycles, with bimonthly questionnaires. We estimated adjusted fecundability ratios (FRs) and confidence intervals (CIs) using proportional probabilities models, controlling for age, income, education, smoking, intercourse frequency, and other lifestyle and reproductive factors.

RESULT(S)

A total of 5,688 women were analyzed, with a mean age of 29.9 years and mean time trying of 2.1 cycles at baseline; 30% had ever been pregnant. At baseline, 75% were using one or more fertility indicators (counting days or charting menstrual cycles [71%], measuring basal body temperature [BBT, 21%], monitoring cervical fluid [39%], using urine LH tests [32%], or feeling for changes in position of the cervix [12%]). Women using any fertility indicator at baseline had higher subsequent fecundability (adjusted FR 1.25, 95% CI 1.16-1.35) than those not using any fertility indicators. For each individual indicator, adjusted FRs ranged from 1.28-1.36, where 1.00 would indicate no relation with fecundability. The adjusted FR for women using a combination of charting days, cervical fluid, and urine LH was 1.48 (95% CI 1.31-1.67) relative to women using no fertility indicators.

CONCLUSION(S)

In a North American preconception cohort study, use of fertility indicators indicating the fertile window was common, and was associated with greater fecundability.

Increased Likelihood of Pregnancy Using an App-Connected Ovulation Test System: A Randomized Controlled Trial

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.

Humanae vitae, ideología de género y futuro biotecnológico

Este artículo tiene como finalidad hacer un comentario breve alusivo a la influencia de la Humanae vitae, cincuenta años después de haber sido publicada. En este contexto se comentan algunos aspectos alusivos a la influencia positiva que confiere esta encíclica al entorno afectivo de la sexualidad, tanto en la edad adulta como en edades temprana de la juventud, ante la influencia de la ideología LGTBI. La visión antropológica de la sexualidad confiere un entorno de respeto por la dignidad de la persona, ante las desviaciones que pueden llegar a presentarse debidas a la influencia de la ideología de género. Finalmente, se citan algunos artículos científicos de índole internacional, que ilustran positivamente la posibilidad de compatibilizar la ciencia con el carácter unitivo y procreativo de la Humanae vitae, en un entorno globalizado.

Timing is crucial: Some critical thoughts on using LH tests to determine women's current fertility

Naturally cycling women reportedly go through a variety of psychological and behavioural changes over menstrual cycle. Evolutionary informed scholars have interpreted such changes as maximising reproductive success. However, concerns have been raised regarding this ovulatory shift hypothesis, since recent studies have yielded inconsistent findings. We suggest that the inconsistent findings regarding the ovulatory shift hypothesis may result from a too simplistic definition of the fertile window. Presently, most studies use LH tests to determine the fertile window. The problem with this "gold standard" is that it builds on the misconception that fertility peaks with ovulation and that ovulation regularly occurs 24 to 48 hours after the LH surge. While commercially available urinary LH test strips are a cheap and easy way to reliably detect LH surges, the LH surge itself marks the impending end of the fertile window. So if women are invited to the laboratory after the LH surge (as is often done for practical reasons) there is a high probability of misclassifying women as fertile when in fact the fertile window has already closed. We discuss possible advancements that may help to increase the accuracy and reliability of determining a woman's individual fertile window, during which any adaptive changes that increase the chance of reproduction should be best observable.

Resolving speculations of methodological inadequacies in the standardized protocol for characterizing women's fertility: Comment on Lobmaier and Bachofner (2018)

Lobmaier and Bachofner (2018) suggest a series of methodological practices to increase the accuracy and reliability of determining a woman's fertile window, claiming the standardized protocol for characterizing women's fertility by Blake et al. (2016) is inadequate. These practices include observing participants for purportedly fertile sessions a considerable time before the LH surge, and using salivary ferning and cervical mucus evaluation as real-time measures of current fertility. Here I explain that Lobmaier and Bachofner's (2018) recommendations decrease rather than increase the likelihood of observing women during peak fertility. I also summarize the pertinent literature on salivary ferning and cervical mucus evaluations, showing that neither method has sufficient sensitivity and specificity to characterize peak fertility. Using meta-analytic data of 10K menstrual cycles, I then show that the protocol provided by Blake et al. (2016) recruits women when conception probability is at its peak and is statistically higher than the window recommended by Lobmaier and Bachofner (2018).

Can apps and calendar methods predict ovulation with accuracy?

OBJECTIVE

The accuracy of prediction of ovulation by cycle apps and published calendar methods was determined by comparing to true probability of ovulation.

METHODS

A total of 949 volunteers collected urine samples for one entire menstrual cycle. Luteinizing hormone was measured to assign surge day, enabling probability of ovulation to be determined across different cycle lengths. Cycle-tracking apps were downloaded. As none provided their methodology, four published calendar-based methods were also examined: standard days, rhythm, alternative rhythm and simple calendar method. The volunteer ovulation data was applied to the app/calendar methods to determine their accuracy.

RESULTS

Mean cycle length was 28 days (range: 23-35); 34% of women believed they had a 28-day cycle, but only 15% did. No LH surge was seen for 99 women. Most likely day of ovulation for a 28-day cycle was day 16 (21%). Accuracy of ovulation prediction was no better than 21% by the apps. The standard days and rhythm methods were most likely to predict ovulation (70% and 89%, respectively) but had very low accuracy.

CONCLUSIONS

Ovulation day varies considerably for any given menstrual cycle length, thus it is not possible for calendar/app methods that use cycle-length information alone to accurately predict the day of ovulation. National Clinical Trial Code: NCT01577147. Registry website: www.clinicaltrials.gov .

Natural conception rates in subfertile couples following fertility awareness training

PURPOSE

To analyze cumulative pregnancy rates of subfertile couples after fertility awareness training.

METHODS

A prospective observational cohort study followed 187 subfertile women, who had received training in self-observation of the fertile phase of the menstrual cycle with the Sensiplan method, for 8 months. The women, aged 21-47 years, had attempted to become pregnant for 3.5 years on average (range 1-8 years) before study entry. Amenorrhea, known tubal occlusion and severe male factor had been excluded. An additional seven women, who had initially been recruited, became pregnant during the cycle immediately prior to Sensiplan training: this is taken to be the spontaneous pregnancy rate per cycle in the cohort in the absence of fertility awareness training.

RESULTS

The cumulative pregnancy rate of subfertile couples after fertility awareness training was 38% (95% CI 27-49%; 58 pregnancies) after eight observation months, which is significantly higher than the estimated basic pregnancy rate of 21.6% in untrained couples in the same cohort. For couples who had been seeking to become pregnant for 1-2 years, the pregnancy rate increased to 56% after 8 months. A female age above 35 (cumulative pregnancy rate 25%, p = 0.06), couples who had attempted to become pregnant for more than 2 years (cumulative pregnancy rate 17%, p < 0.01), all significantly reduce the chances of conceiving naturally at some point.

CONCLUSIONS

Training women to identify their fertile window in the menstrual cycle seems to be a reasonable first-line therapy in the management of subfertility.

Optimizing natural fertility: a committee opinion

This Committee Opinion provides practitioners with suggestions for optimizing the likelihood of achieving pregnancy in couples/individuals attempting conception who have no evidence of infertility. This document replaces the document of the same name previously published in 2013, Fertil Steril 2013;100(3):631-7.

A Bayesian joint model of menstrual cycle length and fecundity

Menstrual cycle length (MCL) has been shown to play an important role in couple fecundity, which is the biologic capacity for reproduction irrespective of pregnancy intentions. However, a comprehensive assessment of its role requires a fecundity model that accounts for male and female attributes and the couple's intercourse pattern relative to the ovulation day. To this end, we employ a Bayesian joint model for MCL and pregnancy. MCLs follow a scale multiplied (accelerated) mixture model with Gaussian and Gumbel components; the pregnancy model includes MCL as a covariate and computes the cycle-specific probability of pregnancy in a menstrual cycle conditional on the pattern of intercourse and no previous fertilization. Day-specific fertilization probability is modeled using natural, cubic splines. We analyze data from the Longitudinal Investigation of Fertility and the Environment Study (the LIFE Study), a couple based prospective pregnancy study, and find a statistically significant quadratic relation between fecundity and menstrual cycle length, after adjustment for intercourse pattern and other attributes, including male semen quality, both partner's age, and active smoking status (determined by baseline cotinine level 100 ng/mL). We compare results to those produced by a more basic model and show the advantages of a more comprehensive approach.

Impact of instruction in the Creighton model fertilitycare system on time to pregnancy in couples of proven fecundity: results of a randomised trial

BACKGROUND

The Creighton Model FertilityCare System (CrMS) teaches women to identify days when intercourse is likely to result in pregnancy. We sought to assess the impact of the CrMS on time to pregnancy (TTP), via per-cycle pregnancy rates (fecundability).

METHODS

We conducted a parallel randomised trial at the University of Utah School of Medicine, 2003-06. Women ages 18-35 years, in a relationship of proven fertility, who desired to conceive, were block-randomised and stratified for age, with allocation concealment by opaque sequentially numbered sealed envelopes. The control group received the advice to have intercourse 2-3 times per week, and the intervention group received CrMS instruction. All women were asked to begin trying to conceive starting the second cycle in the study and were followed actively up to seven cycles, without blinding of research personnel. We calculated descriptive statistics and fecundability, and estimated Cox models for TTP. (Clinicaltrials.gov NCT00161395).

RESULTS

There were 143 women randomised: 71 to the control group (all analysed) and 72 to the CrMS group (69 analysed). The adjusted hazard ratio for the influence of CrMS on TTP was 0.86 [95% confidence interval (CI): 0.53, 1.38]. Fecundability in cycles with intent to conceive was 31% in controls and 36% with CrMS (P = 0.32). By the first cycle, fecundability was 17% in controls, and 4% with CrMS (P = 0.02). No adverse events were reported.

CONCLUSIONS

We found no significant impact of CrMS on TTP or fecundability, but fewer of the women receiving CrMS conceived by the first cycle.

Long-term ongoing pregnancy rate and mode of conception after a positive and negative post-coital test

OBJECTIVE

Many fertility clinics have decided to abolish the post-coital test. Yet, it is a significant factor in prognostic models that predict the spontaneous pregnancy rate within one year. The aim of this study was to evaluate (1) the long-term outcome of infertile couples with a positive or a negative post-coital test during their fertility work-up and (2) the contribution of the different modes of conception.

DESIGN

Retrospective cohort study.

SETTING

Three fertility clinics in the Netherlands, of which two are secondary care training hospitals and is a one tertiary care academic training hospital.

POPULATION

2476 newly referred infertile couples, where a post-coital test was performed in 1624 couples.

METHODS

After basic fertility work-up, couples were treated according to the national treatment protocols.

MAIN OUTCOME MEASURES

Spontaneous and overall ongoing pregnancy rate.

RESULTS

The spontaneous and overall ongoing pregnancy rates after three years were 37.7 and 77.5% after a positive post-coital test compared with 26.9 and 68.8% after a negative test (p < 0.001). Even in couples with severe male factor infertility (total motile sperm count <3) (p = 0.005) and mild male factor infertility (total motile sperm count 3-20) (p < 0.001), there was a significantly higher spontaneous ongoing pregnancy rate, justifying expectant management.

CONCLUSION

After a follow-up of three years a positive post-coital test is still associated with a higher spontaneous and a higher overall ongoing pregnancy rate, even in couples with severe male factor infertility.

The Fertile Window and Biomarkers: A Review and Analysis of Normal Ovulation Cycles

El objetivo de este artículo es revisar los principales conceptos en la literatura acerca de la ventana de la fertilidad en pacientes con ciclos menstruales normales. El énfasis principal del artículo se ha dirigido al análisis de la teoría de Brown de la ovulación, revisar conceptos básicos de la ovulación, secreción y metabolismo de la hormona folículo estimulante, y al estudio clínico, ecográfico y bioquímicos del desarrollo folicular de la ventana de la fertilidad. Este artículo también repasa los biomarcadores clínicos y los diferentes metabolitos endocrinos que delimitan en la fase fértil del ciclo. Se revisan diferentes estudios en los cuales las valoraciones en suero y orina de los esteroides sexuales, han corroborado tener una correlación directa para enmarcar el período fértil. Actualmente tienen relevancia estos conocimientos en diferentes grupos de interés, sobre todo en mujeres con un alto nivel de motivación interesadas en el reconocimiento de su fertilidad, las cuales pueden beneficiarse mediante la aplicación de conocimientos técnicos actuales que detectan la ventana fértil. También estos conocimientos suelen cobrar importancia en aquellas personas que pertenecen a programas de regulación de la fertilidad (PRF), con intención de distanciar un embarazo, o de reconocer el periodo fértil del ciclo para conseguir un embarazo espontáneamente, o mediante programas de NaProTecnología. Otros grupos de interés, son aquellos en los cuales no se tiene experiencia en cursos de PRF, pero desean mejorar sus conocimientos en el reconocimiento de la fertilidad por medio de una breve entrevista, o por medio de cursos de orientación familiar.

Comparison of a digital ovulation test with three popular line ovulation tests to investigate user accuracy and certainty

OBJECTIVES

To determine the accuracy and certainty with which volunteers interpreted results of a digital ovulation test, Clearblue digital ovulation test (CB-DOT), compared with three home use non-digital visual ovulation tests: Clearblue ovulation test (CB-OT), First Response (FR) and Answer (AN).

METHODS

A total of 72 female volunteers aged 18 - 45 years interpreted test results from each of the four ovulation tests to determine the day of the luteinising hormone surge in 40 individual menstrual cycles. We used urine previously collected from 25 volunteers. The accuracy with which volunteers interpreted the test results was calculated by comparing their results with results obtained by trained technicians using a blinded test regime. For each of the four tests, volunteers were also asked to rate seven attributes of certainty and eight attributes of preference. The primary objective was to compare the accuracy with which volunteers read results from CB-DOT when compared to three visual-based line ovulation tests.

RESULTS

A significantly higher percentage of volunteers/technicians agreed on the interpretation of the results from CB-DOT (97.3%) than for CB-OT (83.5%; p = 0.0153), AN (73%; p = 0.0011) or FR (64.3%; p = 0.0001). CB-DOT was also found to have significantly better Likert scores than CB-OT, FR and AN for all seven attributes of certainty and was the test that 97.2% of volunteers preferred.

CONCLUSIONS

Women can misread the results of line ovulation tests. Over 97% of volunteers correctly read the result of CB-DOT. CB-DOT was also the test that women read with most certainty and the test that most users preferred.

Intrauterine insemination versus timed intercourse with clomiphene citrate in polycystic ovary syndrome: a randomized controlled trial

OBJECTIVE

To compare the efficacy of intrauterine insemination vs. timed intercourse with clomiphene citrate as a first-line treatment for anovulatory infertility associated with polycystic ovary syndrome.

DESIGN

A randomized controlled trial following the CONSORT criteria.

SETTING

A university hospital and a private practice setting.

PATIENTS

188 women (525 cycles) with polycystic ovary syndrome.

MAIN OUTCOME MEASURES

Women received three consecutive cycles of ovulation induction with clomiphene citrate and intrauterine insemination (n=93, 259 cycles) or three consecutive cycles of clomiphene citrate with timed intercourse (n=95, 266 cycles).

OUTCOME MEASURES

Clinical pregnancy rate per cycle, number of growing and mature follicles, serum estradiol, endometrial thickness at the hCG day, serum progesterone, ovulation, miscarriage and live birth rates.

RESULTS

There were no differences between the two groups regarding the clinical pregnancy rate per cycle or per woman (8.49 vs. 7.89% and 23.6 vs. 22.1%; p=0.26 and p=0.33, respectively). Two twin pregnancies occurred in each group. Miscarriage and live birth rates were comparable (18.1 vs. 19% and 19.35 vs. 17.89%; p=0.31 and p=0.33, respectively). No ectopic, higher-order pregnancies or cases of ovarian hyperstimulation syndrome occurred. No differences were found regarding the number of follicles, serum progesterone, ovulation rates, estradiol levels or endometrial thickness at the hCG day (7.7±0.4 vs. 7.5±0.6mm; p=0.54).

CONCLUSIONS

Ovulation induction with clomiphene citrate and timed intercourse is as effective as that with intrauterine insemination for achieving pregnancy in polycystic ovary syndrome and could represent the initial treatment option, being less invasive and less expensive than intrauterine insemination.

Severity of oligo-asteno-teratozoospermia no longer determines overall success rate in male subfertility

In this longitudinal multicentre cohort study, the overall ongoing pregnancy rate after current evidence-based management in male subfertility was studied. All subfertile couples who visited the fertility clinic for the first time between 2002 and 2006, and had male subfertility as a single diagnosis (n = 762 of 2476 couples), were included in this study. Couples were grouped by the severity of male factor. Group I (n = 541) had a total motile sperm count (TMSC) 1-20 × 10(6). Group II (n = 161) had a TMSC <1 × 10(6). Group III (n = 60) had azoospermia. The overall ongoing pregnancy rate was 65.5% (500/762). The overall ongoing pregnancy rates in group I (69.3%) and group II (61.5%) were comparable (p = 0.06). However, group I and group II conceived significantly more frequently than group III (43.3%) (group I vs. group III p < 0.001 and group II vs. group III p = 0.02, respectively). Moreover, the spontaneous ongoing pregnancy rate in group I was 35.3%, in group II 22.4% and in group III, 1.7% (group I vs. group II p = 0.002; group I vs. group III p < 0.001; group II vs. group III p < 0.001). Thus, despite a significant difference in spontaneous ongoing pregnancy rates, except for azoospermia, the overall ongoing pregnancy rates, regardless of the severity of the male factor, were comparable. Couples with poorer sperm parameters, however, have to undergo more invasive treatment to reach the same goal.

The molecular basis of recurrent pregnancy loss: impaired natural embryo selection

Recurrent pregnancy loss (RPL) is a common and distressing disorder. Chromosomal errors in the embryo are the single most common cause, whereas uterine factors are invariably invoked to explain non-chromosomal miscarriages. These uterine factors are, however, poorly defined. The ability of a conceptus to implant in the endometrium is normally restricted to a few days in the menstrual cycle. A limited 'window of implantation' ensures coordinated embryonic and endometrial development, thereby minimizing the risk of late implantation of compromised embryos. In this paper, we review emerging evidence, indicating that RPL is associated with impaired differentiation of endometrial stromal cells into specialized decidual cells. From a functional perspective, this differentiation process, termed decidualization, is not only critical for placental development but also signals the end of the implantation window and bestows on the endometrium the ability to recognize, respond to and eliminate implanting compromised embryos. Thus, we propose that spontaneous decidualization of the human endometrium, which inevitably causes menstrual shedding in the absence of a viable conceptus, serves as functional 'window for natural embryo selection'. Conversely, impaired decidualization predisposes to late implantation, negates embryo quality control and causes early placental failure, regardless of the embryonic karyotype. This pathological pathway also explains the common observation that many RPL patients seem exceptionally fertile, often conceiving within one or two cycles. Thus, as the clinical correlate of inappropriate uterine receptivity, 'superfertility' should be considered as a genuine reproductive disorder that requires targeted intervention.

Joint modeling of intercourse behavior and human fecundability using structural equation models

Human fecundability is defined as the probability of conception during a menstrual cycle among couples at risk for pregnancy. It is highly relevant for understanding human reproduction and represents a series of highly interrelated and timed processes. The statistical literature has recognized the need to incorporate both biological and behavioral factors (Barrett and Marshall, 1969; Dunson and Stanford, 2005) when modeling conception probabilities, given that intercourse during the fertile window is a necessary but not sufficient criterion for conception. The heterogeneity of behaviors such as the timing and frequency of intercourse in a menstrual cycle needs to be considered when estimating conception. Here we propose a joint model of intercourse behavior and human fecundability through a classic conception probability model and a structural equation model (SEM) to accommodate intercourse during the menstrual cycle. The SEM part of the proposed model allows the dependency between intercourse behaviors on consecutive days in a menstrual cycle to vary across days. Consequently, the proposed model can accommodate not only a broad variety of intercourse patterns and dependency structures but also general covariate effects. Finally, we present a detailed analysis of the New York State Angler Cohort Prospective Pregnancy Study to illustrate the proposed methodology.

Cumulative pregnancy probabilities among couples with subfertility: effects of varying treatments

OBJECTIVE

To model the cumulative probability of pregnancy among couples with subfertility without a definitive diagnosis, according to different treatment strategies.

DESIGN

A beta distribution of fecundity was fitted that reproduced the cumulative probability of pregnancy in prospective studies of natural fertility, and this distribution was applied to simulated cohorts starting with one million couples each. Probabilities of pregnancy were generated for each cycle of each couple.

SETTING

Simulation study.

PATIENT(S)

Hypothetic subfertile population.

INTERVENTION(S)

After 2 or 4 years of attempting pregnancy and diagnostic evaluation to exclude anovulation, tubal obstruction, and severe male factor, simulated treatments were applied to the remaining nonpregnant couples, with treatment effects based on published literature.

MAIN OUTCOME MEASURE(S)

Simulated cumulative probability of pregnancy.

RESULT(S)

Initially, the cumulative probability of pregnancy was highest for early treatment with IVF, but over time, conservative treatment or frequent intercourse approached the same cumulative probability.

CONCLUSION(S)

In couples without clear indications for IVF, the main benefit of early IVF may be to shorten time to pregnancy, a benefit that must be weighed against costs and potential adverse outcomes. Couples should be encouraged to maintain regular intercourse to maximize chances of pregnancy, even after unsuccessful treatment attempts.

Polychlorinated biphenyl serum concentrations, lifestyle and time-to-pregnancy

BACKGROUND

Consumption of fish contaminated with polychlorinated biphenyls (PCBs) and prenatal PCB serum concentrations have been associated with a longer time-to-pregnancy (TTP). However, the relationship between preconception serum PCBs concentrations and TTP has not been previously studied.

METHODS

Eighty-three women (contributing 442 menstrual cycles) planning pregnancies completed daily diaries regarding menstruation, intercourse, home pregnancy test results, and reported use of alcohol and cigarettes. TTP denoted the number of observed menstrual cycles required for pregnancy. Preconception blood specimens underwent toxicologic analysis for 76 PCB congeners via gas chromatography with electron capture; serum lipids were quantified with enzymatic methods. A priori, PCB congeners were summed into a total and three groupings-estrogenic, anti-estrogenic and other-and entered into discrete analogs of Cox models with time-varying covariates to estimate fecundability odds ratios (FOR) and corresponding 95% confidence intervals (CIs).

RESULTS

Estrogenic and anti-estrogenic PCB concentrations (ng/g serum) conferred reduced FORs in fully adjusted models (0.32; 95% CI 0.03, 3.90 and 0.01: 95% CI < 0.00, 1.99, respectively). Reduced FORs (0.96) were observed for alcohol consumption standardized to a 28-day menstrual cycle in the same adjusted model (FOR = 0.96; 95% CI 0.93, 1.00).

CONCLUSIONS

These data suggest that environmental exposures including those amenable to change, such as alcohol consumption, may impact female fecundity. The findings are sensitive to model specification and PCB groupings, underscoring the need to further assess the impact of chemical mixtures on sensitive reproductive outcomes, such as TTP, especially in the context of lifestyle factors which are amenable to change, thereby improving reproductive health.

Predicting fertility

Various predictors of fertility have been described, suggesting that none are ideal. The literature on tests of ovarian reserve is largely limited to women undergoing in vitro fertilization, and is reliant on the use of surrogate markers, such as cycle cancellation and number of oocytes retrieved, as reference standards. Currently available prediction models are far from ideal; most are applicable only to subfertile women seeking assisted reproduction, and lack external validation. Systematic reviews and meta-analyses of predictors of fertility are limited by their heterogeneity in terms of the population sampled, predictors tested and reference standards used. There is an urgent need for consensus in the design of these studies, definition of abnormal tests, and, above all, a need to use robust outcomes such as live birth as the reference standard. There are no reliable predictors of fertility that can guide women as to how long childbearing can be deferred.

Nitric oxide extends the oocyte temporal window for optimal fertilization

Deteriorating oocyte quality is a critical hurdle in the management of infertility, especially one associated with advancing age. In this study, we explore the role of nitric oxide (NO) on the sustenance of oocyte quality postovulation. Sibling oocytes from superovulated mice were subjected to intracytoplasmic sperm injection (ICSI) with cauda-epididymal spermatozoa following exposure to either the NO donor, S-nitroso-N-acetylpenicillamine (SNAP, 0.23 microM/min), an NO synthase (NOS) inhibitor, N omega-nitro-L-arginine methyl ester (L-NAME, 1 mM), or an inhibitor of soluble guanylyl cyclase (sGC), 1H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-1-one (ODQ, 100 microM); while their sibling oocytes were subjected to ICSI either before (young) or after culture for the corresponding period of time (old). Outcomes of normal fertilization, cleavage, and development to the morula and blastocyst stages were compared. Embryos from each subgroup were also subjected to TUNEL assay for apoptosis. A significant deterioration in the ability of the oocytes to undergo normal fertilization and development to morula and blastocyst stages occurred among oocytes aged in culture medium compared to their sibling cohorts subjected to ICSI immediately after ovulation (P<0.05). This deterioration was prevented in oocytes exposed to SNAP. In contrast, exposure to L-NAME or ODQ resulted in a significant compromise in fertilization and development to the morula and blastocyst stages (P<0.05). Finally, apoptosis was noted in embryos derived from aged oocytes and those exposed to L-NAME or ODQ, but not in embryos derived from young oocytes or oocytes exposed to SNAP. Thus, NO is essential for sustenance of oocyte quality postovulation.

What is the most valid comparison treatment in trials of intrauterine insemination, timed or uninfluenced intercourse? A systematic review and meta-analysis of indirect evidence

BACKGROUND

Timed intercourse (TI), which is the usual control treatment in trials of intrauterine insemination (IUI), is not a typical coital activity and could impair fertility. This review summarizes the trials of IUI of male partner's prepared semen among subfertile couples according to whether the control group had TI or expectant management.

METHODS

A search of relevant databases and bibliographies until February 2008 yielded 150 citations of which 31 were potentially relevant and 11 met all criteria. The total estimates of the differences in pregnancy rates per couple were calculated with weights equal to the inverse variance. The primary analysis was a categorical meta-analysis by the type of control treatment (TI or expectant management).

RESULTS

In 11 trials with 13 comparisons of IUI and intercourse among 1329 couples with subfertility, the average difference in pregnancy rate between IUI and controls was 6.1% in trials with TI and 3.9% in trials with expectant management, as the control. The adjusted indirect estimate of the difference between the types of control groups was 2.8% (95% CI -6.3, 10.7). The difference by type of control treatment was not significant, neither in the 11 most relevant trials (P = 0.82), nor in a broader group of 19 trials and 2512 patients (P = 0.20).

CONCLUSIONS

The additional benefit accruing to IUI, where TI is the control, is not significant, but it is consistent with the possibility that pregnancy may be less likely in TI controls than in expectant management controls.