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

Fertility treatments and the risk of preterm birth among women with subfertility: a linked-data retrospective cohort study

Background

In vitro fertilization (IVF) births contribute to a considerable proportion of preterm birth (PTB) each year. However, there is no formal surveillance of adverse perinatal outcomes for less invasive fertility treatments. The study objective was to describe associations between fertility treatment (in vitro fertilization, intrauterine insemination, usually with ovulation drugs (IUI), or ovulation drugs alone) and preterm birth, compared to no treatment in subfertile women.

Methods

The Fertility Experiences Study (FES) is a retrospective cohort study conducted at the University of Utah between April 2010 and September 2012. Women with a history of primary subfertility self-reported treatment data via survey and interviews. Participant data were linked to birth certificates and fetal death records to asses for perinatal outcomes, particularly preterm birth.

Results

A total 487 birth certificates and 3 fetal death records were linked as first births for study participants who completed questionnaires. Among linked births, 19% had a PTB. After adjustment for maternal age, paternal age, maternal education, annual income, religious affiliation, female or male fertility diagnosis, and duration of subfertility, the odds ratios and 95% confidence intervals (CI) for PTB were 2.17 (CI 0.99, 4.75) for births conceived using ovulation drugs, 3.17 (CI 1.4, 7.19) for neonates conceived using IUI and 4.24 (CI 2.05, 8.77) for neonates conceived by IVF, compared to women with subfertility who used no treatment during the month of conception. A reported diagnosis of female factor infertility increased the adjusted odds of having a PTB 2.99 (CI 1.5, 5.97). Duration of pregnancy attempt was not independently associated with PTB. In restricting analyses to singleton gestation, odds ratios were not significant for any type of treatment.

Conclusion

IVF, IUI, and ovulation drugs were all associated with a higher incidence of preterm birth and low birth weight, predominantly related to multiple gestation births.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12978-022-01363-4.

Infertility treatments such as in vitro fertilization are associated with preterm birth, but less is known about how other less invasive treatments contribute to preterm birth. This study compares different types of fertility treatments and rates of preterm birth with women who are also struggling with infertility but did not use fertility treatments at the time of their pregnancy. 490 women were recruited at the University of Utah between 2010 and 2012. Participants were asked to complete a survey and were linked to birth certificate and fetal death certificate data. Women who used in vitro fertilization were 4.24 times more likely to have a preterm birth than those who used no treatment. Use of intrauterine insemination were 3.17 times more likely to have a preterm birth than those who used no treatment at time of conception. Ovulation stimulating drugs were 2.17 times more likely to have a preterm birth. Having female factor infertility was also associated with higher odds of having preterm birth. For those who are having trouble conceiving, trying less invasive treatments to achieve pregnancy might reduce their risk of preterm birth.

Restorative reproductive medicine for infertility in two family medicine clinics in New England, an observational study

BACKGROUND

Restorative reproductive medicine (RRM) seeks to identify and correct underlying causes and factors contributing to infertility and reproductive dysfunction. Many components of RRM are highly suitable for primary care practice. We studied the outcomes amongst couples who received restorative reproductive medicine treatment for infertility in a primary care setting.

METHODS

Two family physicians in Massachusetts trained in a systematic approach to RRM (natural procreative technology, or NaProTechnology) treated couples with infertility. We retrospectively reviewed the characteristics, diagnoses, treatments, and outcomes for all couples treated during the years 1989 to 2014. We compared pregnancy and live birth by clinical characteristics using Kaplan-Meier analysis. We employed the Fleming-Harrington weighted Renyi test or the logrank test to compare the cumulative proportion with pregnancy or with live birth.

RESULTS

Among 370 couples beginning treatment for infertility, the mean age was 34.8 years, the mean prior time trying to conceive was 2.7 years, and 27% had a prior live birth. The mean number of diagnoses per couple was 4.9. Treatment components included fertility tracking with the Creighton Model FertilityCare System (80%); medications to enhance cervical mucus production (81%), to stimulate ovulation (62%), or to support the luteal phase (75%); and referral to female laparoscopy by a surgeon specializing in endometriosis (46%). The cumulative live birth rate at 2 years was 29% overall; this was significantly higher for women under age 35 (34%), and for women with body mass index < 25 (40%). There were 2 sets of twins and no higher-order multiple gestations. Of the 63 births with data available, 58 (92%) occurred at term.

CONCLUSIONS

Family physicians can provide a RRM approach for infertility to identify underlying causes and promote healthy term live births. Younger women and women with body mass index < 25 are more likely to have a live birth.

Fertility Treatment, Use of in Vitro Fertilization, and Time to Live Birth Based on Initial Provider Type

PURPOSE

To explore the relationship between the type of clinician (generalist vs subspecialist) initially seen by infertile women, the treatment received, and the time to pregnancy.

METHODS

We analyzed mixed-mode questionnaire data from 867 women with primary infertility enrolled into a retrospective cohort through population- and fertility clinic-based sampling. We compared women presenting first to generalist providers with women presenting first to fertility subspecialists, with the main outcomes of receiving in vitro fertilization (IVF), time to pregnancy, and live birth.

RESULTS

The first contact for most (84%) women with infertility was a generalist provider. Only 8% of women sought care first from a fertility subspecialist, and these women were older and had been trying longer to conceive. Women who presented first to a generalist provider were less likely to receive IVF (adjusted odds ratio, 0.48; 95% confidence interval, 0.28-0.82), were equally likely to achieve pregnancy, and had similar times to pregnancy (adjusted hazard ratio, 1.11; 95% confidence interval, 0.80-1.53) compared with women who presented first to a subspecialist.

CONCLUSIONS

Generalist providers are frequently the first point of care for women with difficulty conceiving and are uniquely positioned to promote the balanced management of infertility.

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.

Natural conception: repeated predictions over time

STUDY QUESTION

How can we predict chances of natural conception at various time points in couples diagnosed with unexplained subfertility?

SUMMARY ANSWER

We developed a dynamic prediction model that can make repeated predictions over time for couples with unexplained subfertility that underwent a fertility workup at a fertility clinic.

WHAT IS KNOWN ALREADY

The most frequently used prediction model for natural conception (the 'Hunault model') estimates the probability of natural conception only once per couple, that is, after completion of the fertility workup. This model cannot be used for a second or third time for couples who wish to know their renewed chances after a certain period of expectant management.

STUDY DESIGN, SIZE, DURATION

A prospective cohort studying the long-term follow-up of subfertile couples included in 38 centres in the Netherlands between January 2002 and February 2004. Couples with bilateral tubal occlusion, anovulation or a total motile sperm count <1 × 10⁶ were excluded.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The primary endpoint was time to natural conception, leading to an ongoing pregnancy. Follow-up time was censored at the start of treatment or at the last date of contact. In developing the new dynamic prediction model, we used the same predictors as the Hunault model, i.e. female age, duration of subfertility, female subfertility being primary or secondary, sperm motility and referral status. The performance of the model was evaluated in terms of calibration and discrimination. Additionally, we assessed the utility of the model in terms of the variability of the calculated predictions.

MAIN RESULTS AND THE ROLE OF CHANCE

Of the 4999 couples in the cohort, 1053 (21%) women reached a natural conception leading to an ongoing pregnancy within a mean follow-up of 8 months (5th and 95th percentile: 1-21). Our newly developed dynamic prediction model estimated the median probability of conceiving in the first year after the completion of the fertility workup at 27%. For couples not yet pregnant after half a year, after one year and after one and a half years of expectant management, the median probability of conceiving over the next year was estimated at 20, 15 and 13%, respectively. The model performed fair in an internal validation. The prediction ranges were sufficiently broad to aid in counselling couples for at least two years after their fertility workup.

LIMITATIONS, REASONS FOR CAUTION

The dynamic prediction model needs to be validated in an external population.

WIDER IMPLICATIONS OF THE FINDINGS

This dynamic prediction model allows reassessment of natural conception chances after various periods of unsuccessful expectant management. This gives valuable information to counsel couples with unexplained subfertility that are seen for a fertility workup.

STUDY FUNDING/COMPETING INTERESTS

This study was facilitated by grant 945/12/002 from ZonMW, The Netherlands Organization for Health Research and Development, The Hague, The Netherlands. No competing interests.

Methods for a Retrospective Population-based and Clinic-based Subfertility Cohort Study: the Fertility Experiences Study

BACKGROUND

Most cohort-based research for subfertility has been conducted in clinic-based cohorts, which may differ from population-based cohorts.

METHODS

We retrospectively recruited parallel cohorts of subfertile women: one by sampling two specialty fertility clinics in Utah, and one by population-based sampling based on marriage and birth records. The index date (of first clinic visit or subfertility status) was between 2000 and 2009, and we linked the women recruited to subsequent birth certificate records through December 2010.

RESULTS

We enrolled 459 women through clinic-based sampling and 501 women through population-based sampling. Clinic-based women were older, had higher annual household income and more likely to have had a most intensive treatment of intrauterine insemination (31%) or in vitro fertilisation (46%) than women from population recruitment (19% and 14% respectively). Conversely, they were less likely to have received no medical treatment (9%) compared to women from population recruitment (41%). For both types of sampling, prior to eligibility screening, non-responders were less likely to link to a live birth than responders: 51% vs. 58% for clinic-based, and 69% vs. 76% for the population-based with an index date in 2004.

CONCLUSIONS

Population-based sampling for subfertility cohort research identifies women who were more likely to have had less intensive treatment or no treatment. However, in both clinic-based and population-based sampling, women who have had a live birth are more likely to respond to retrospective recruitment.

A Survey on Main Semen Parameters in Natural Pregnancy and Intrauterine Insemination: Are There Any Significant Differences?

Intrauterine insemination (IUI) is a treatment of choice compared with other invasive and expensive techniques of assisted reproduction. Sperm quality is used to predict its outcome and success. Establishing threshold levels for sperm parameters is useful to avoid spending time and money to do other assisted reproductive techniques. This study was carried out to compare various semen parameters in a group of men eligible to participate in an IUI program with those of fertile men whose wives were pregnant at the time of the study. Two hundred and thirty-four semen samples were evaluated from subfertile men whose partners were candidates for IUI and 234 semen samples were evaluated from fertile men whose partners were pregnant less than 12 weeks. To assess the sensitivity and specificity of the main semen parameters, receiver operating characteristic (ROC) curves were used. Normal sperm morphology is more sensitive and specific compared with its progressive motility and concentration. No significant differences in various semen parameters of fertile men and those of the male partners of IUI candidates were observed. ROC analysis identified that sperm normal morphology using strict criteria may be a good indicator of fertility status in men. No significant difference in various semen parameters between the male partners of IUI candidates and the fertile men was seen. However, utilizing ROC curves, sperm morphology using strict criteria could be a good predictor of fertility.

Fertility treatments and adverse perinatal outcomes in a population-based sampling of births in Florida, Maryland, and Utah: a cross-sectional study

OBJECTIVE

To investigate perinatal outcomes associated with fertility treatments, including assisted reproductive technology (ART), intrauterine insemination with ovulation stimulation (IUI), and ovulation stimulation alone (OS).

DESIGN

Population-representative cross-sectional survey of women with live births, 2004-2008.

SETTING

Florida, Maryland, and Utah, USA.

SAMPLE

21 803 women, weighted to represent 1 022 597 women.

METHODS

Survey and birth certificate data were analysed with logistic regression models adjusted for age, education, race, income, and parity, using separate models for singletons and all births. We used two referent groups: (1) women who never used fertility treatment and (2) subfertile women conceiving without treatment.

MAIN OUTCOME MEASURES

Preterm birth (<37 weeks), very preterm birth (<34 weeks), low birthweight (<2500 g), and very low birthweight (<1500 g).

RESULTS

Referent group 1: In singletons, ART was associated with preterm birth (OR 3.28; 95% CI 1.74, 6.20) and low birthweight (OR 2.91; 95% CI 1.99, 4.26). OS was also associated with low birthweight (OR 1.62; 95% CI 1.19, 2.19). Including all births, treatment was associated with preterm birth and low birthweight: ART (OR 6.21; 95% CI 4.21, 9.16 and OR 6.51; 95% CI 4.85, 8.73); IUI (OR 2.10; 95% CI 1.24, 3.56 and OR 2.41; 95% CI 1.54, 3.76); OS (OR 1.40; 95% CI 1.01, 1.94 and OR 2.10; 95% CI 1.60, 2.75), respectively. Referent group 2: ART was associated with both outcomes in all births, but not singletons.

CONCLUSIONS

Preterm birth and low birthweight associated with fertility treatments are largely attributable to multiple gestation, but are also related to underlying subfertility.

TWEETABLE ABSTRACT

Preterm birth is associated with subfertility, and with fertility treatments through multiple gestation.

Use of fertility treatments in relation to the duration of pregnancy attempt among women who were trying to become pregnant and experienced a live birth

The purpose of this study was to compare the utilization of medical help for fertility among women who reported up to a year versus more than a year of trying to become pregnant and to describe the characteristics of those women seeking early treatment. Data from the 2004-2008 Pregnancy Risk Assessment Monitoring System (PRAMS) survey were used to assess attempt duration and use of fertility treatments in a sample of 9,517 women who had a recent live birth in Utah. PRAMS respondents who were trying to become pregnant at the time of conception were asked questions about fertility treatments (sampling n = 5,238; representative n = 153,036). Univariate and bivariate analyses were used to describe and compare characteristics of women who sought treatment after attempting pregnancy for a year or less and women who waited at least a year to seek treatment. Among women who were trying to become pregnant, 9.5 % reported using some medical assistance to conceive. Among the women trying to become pregnant, 89.3 % had been trying for ≤12 months and 10.7 % reported having tried >12 months. 5.2 % of those trying to become pregnant for up to a year reported use of fertility treatment, compared with 45.8 % of those trying for a year or more. Women who had previous live births were significantly more likely to use early treatment than nulliparous women (aOR = 2.4, 95 % CI = 1.5, 3.9). The use of fertility drugs and other treatments were more common than ART among recipients of early treatment (aOR = 3.7, 95 % CI = 1.7, 7.9). Some women may be receiving fertility treatment before it is clinically indicated. Instead of invasive treatment, these women may benefit from preconception counseling on folic acid, healthy prepregnancy weight and use of ovulation monitoring to time intercourse.

Differences in cumulus cells gene expression between modified natural and stimulated in vitro fertilization cycles

PURPOSE

The aim of our study was to determine whether there are any differences in the cumulus cell gene expression profile of mature oocytes derived from modified natural IVF and controlled ovarian hyperstimulation cycles and if these changes could help us understand why modified natural IVF has lower success rates.

METHODS

Cumulus cells surrounding mature oocytes that developed to morulae or blastocysts on day 5 after oocyte retrieval were submitted to microarray analysis. The obtained data were then validated using quantitative real-time PCR.

RESULTS

There were 66 differentially expressed genes between cumulus cells of modified natural IVF and controlled ovarian hyperstimulation cycles. Gene ontology analysis revealed the oxidation-reduction process, glutathione metabolic process, xenobiotic metabolic process and gene expression were significantly enriched biological processes in MNIVF cycles. Among differentially expressed genes we observed a large group of small nucleolar RNA's whose role in folliculogenesis has not yet been established.

CONCLUSION

The increased expression of genes involved in the oxidation-reduction process probably points to hypoxic conditions in modified natural IVF cycles. This finding opens up new perspectives for the establishment of the potential role that oxidation-reduction processes have in determining success rates of modified natural IVF.

Efficacy of sperm motility after processing and incubation to predict pregnancy after intrauterine insemination in normospermic individuals

BACKGROUND

Intrauterine insemination (IUI) is widely used to treat infertility, and its adequate indication is important to obtain good pregnancy rates. To assess which couples could benefit from IUI, this study aimed to evaluate whether sperm motility using a discontinuous gradient of different densities and incubation in CO2 in normospermic individuals is able to predict pregnancy.

METHODS

A total of 175 couples underwent 175 IUI cycles. The inclusion criteria for women were as follows: 35 years old or younger (age range: from 27 to 35 years) with normal fallopian tubes; endometriosis grades I-II; unexplained infertility; nonhyperandrogenic ovulatory dysfunction. Men with normal seminal parameters were also included. All patients underwent ovarian stimulation with clomiphene citrate and human hMG or r-FSH. When one or (at most) three follicles measuring 18 to 20 mm were observed, hCG (5000 UI) or r-hCG (250 mcg) was administered and IUI performed 36-40 h after hCG. Sperm processing was performed using a discontinuous concentration gradient. A 20 microliters aliquot was incubated for 24 h at 37 degrees C in 5% CO2 following a total progressive motility analysis. The Mann-Whitney and Chi-square tests, as well as a ROC curve were used to determine the cutoff value for motility.

RESULTS

Of the 175 couples, 52 (in 52 IUI cycles) achieved clinical pregnancies (CP rate per cycle: 29.7%). The analysis of age, duration and causes of infertility did not indicate any statistical significance between pregnancy and no pregnancy groups, similar to the results for total sperm count and morphology analyses, excluding progressive motility (p < 0.0001). The comparison of progressive motility after processing and 24 h after incubation between these two groups indicated that progressive motility 24 h after incubation was higher in the pregnancy group. The analysis of the progressive motility of the pregnancy group after processing and 24 h after incubation has not shown any motility difference at 24 h after incubation; additionally, in couples who did not obtain pregnancy, there was a statistically significant decrease in progressive motility 24 h after incubation (p < 0.0001). The ROC curve analysis generated a cutoff value of 56.5% for progressive motility at 24 h after incubation and this cutoff value produced 96.1% sensitivity, 92.7% specificity, 84.7% positive predictive value and 98.3% negative predictive value.

CONCLUSIONS

We concluded that the sperm motility of normospermic individuals 24 h after incubation at 37 degrees C in 5% CO2, with a cutoff value of 56.5%, is predictive of IUI success.

Infertility treatment in a population-based sample: 2004-2005

To describe the characteristics of women seeking infertility treatment and the types of fertility treatment sought within a population-based sample. We analyzed data from the cross-sectional Pregnancy Risk Assessment Monitoring System (PRAMS) of women with a live birth using data from seven states. Logistic regression was used to determine factors associated with infertility treatment utilization. Infertility treatment was reported by 10.5% of women who were trying to become pregnant. The most common treatment reported was fertility enhancing drugs (29%), followed by assisted reproductive technology including in vitro fertilization (21%), and artificial insemination together with fertility enhancing drugs (15%). Some women reported using other types of treatment (23%). The PRAMS data provide insights into the use of infertility treatment among women giving birth in the United States. Further research is needed to understand the true prevalence of infertility, factors that influence treatment choices, and the longitudinal impact of infertility treatment on outcomes.