Probability Of Birth Research Articles

Partner support and relationship quality as potential resources for childbirth and the transition to parenthood

BackgroundThe aim of the present paper was to explore the role of partners for the stressful life events of birth and the transition to parenthood.MethodsIn a first prospective longitudinal study (N = 304 dyads) we tested whether relationship quality positively predicted fewer interventions during labor and birth, a more positive birth experience, and better well-being during the first six weeks after birth. In a second study we surveyed mothers (N = 980; retrospective quasi-experimental design) who had given birth during the first lockdown of the COVID-19 pandemic in spring 2020 – some in the absence of their partners – to test the assumption that regardless of relationship quality, the presence of the partner was positively related to low-intervention births and the birth experience.ResultsThe results of the longitudinal study (Study 1) could be integrated into a Single Indicator model. They revealed that a high relationship quality assessed between week 5 and week 25 of pregnancy had a positive effect on birth experience for the mother and on psychological well-being during the transition to parenthood for both mothers and fathers. Results of the retrospective quasi-experimental field study (Study 2) revealed that the continuous presence of the partner was associated with a higher probability of a low-intervention birth and a more positive birth experience. Presence of a partner for only part of the birth did not positively predict labor and birth, but did positively predict the birth experience. The effects were independent of relationship quality.ConclusionThe results of both studies highlight the importance of partners for psychological well-being during labor and birth and the transition to parenthood.

Assessing the predictive accuracy of the new vaginal birth after cesarean delivery calculator

The vaginal birth after cesarean delivery calculator by the Maternal-Fetal Medicine Units Network was created to help providers counsel patients on predicted success of trial of labor after cesarean delivery using individualized risk assessment. The inclusion of race and ethnicity as predictors of vaginal birth after cesarean delivery in the 2007 calculator was problematic and potentially exacerbated racial disparities in obstetrics. Thus, a modified calculator without race and ethnicity was published in June 2021. This study aimed to assess the accuracy of the 2007 and 2021 Maternal-Fetal Medicine Units vaginal birth after cesarean delivery calculators in predicting vaginal birth after cesarean delivery success among racial/ethnic minority patients receiving obstetrical care at a single urban tertiary medical center. All patients with 1 previous low transverse cesarean delivery who underwent a trial of labor at term with a vertex singleton gestation at an urban tertiary medical center from May 2015 to December 2018 were reviewed. Demographic and clinical data were collected retrospectively. Associations between maternal characteristics and success of vaginal birth after cesarean delivery were assessed using univariate and multivariable logistic regression. Predicted vaginal birth after cesarean delivery success rates using the Maternal-Fetal Medicine Units calculator were compared with actual outcomes (ie, successful trial of labor after cesarean delivery/vaginal birth after cesarean delivery vs repeated cesarean delivery) across each racial and ethnic group. A total of 910 patients met eligibility criteria and attempted trial of labor after cesarean delivery; 662 (73%) achieved vaginal birth after cesarean delivery. The rate of vaginal birth after cesarean delivery was highest among Asian women (81%) and lowest among Black women (61%). Univariate analyses demonstrated that success of vaginal birth after cesarean delivery was associated with maternal body mass index <30 kg/m2, history of vaginal delivery, and absence of indication of arrest of dilation or descent for previous cesarean delivery. Multivariate analyses evaluating predictors of vaginal birth after cesarean delivery reported in the 2021 calculator showed that maternal age, history of arrest disorder for previous cesarean delivery, and treated chronic hypertension were not significant in our patient population. Most patients who were of White, Asian, or "Other" race with a vaginal birth after cesarean delivery had a 2007 calculator-predicted probability of vaginal birth after cesarean delivery of >65%, whereas most Black and Hispanic patients with a vaginal birth after cesarean delivery were more likely to have a predicted probability of vaginal birth after cesarean delivery between 35% and 65% (P<.001). Most White, Asian, and Other-race patients with a repeated cesarean delivery had a 2007 calculator-predicted probability of vaginal birth after cesarean delivery of >65%, whereas most Black and Hispanic patients with a repeated cesarean delivery had a predicted probability of vaginal birth after cesarean delivery between 35% and 65%. Across all racial and ethnic groups, most patients with a vaginal birth after cesarean delivery had a 2021 calculator-predicted probability of vaginal birth after cesarean delivery of >65%. The inclusion of race/ethnicity in the 2007 Maternal-Fetal Medicine Units vaginal birth after cesarean delivery calculator underestimated predicted vaginal birth after cesarean delivery success rates among Black and Hispanic patients receiving obstetrical care at an urban tertiary medical center. Thus, we support the use of the 2021 vaginal birth after cesarean delivery calculator without race/ethnicity. Excluding race and ethnicity from vaginal birth after cesarean delivery counseling may be one way in whichproviders can ultimately contribute toward the reduction of racial and ethnic disparity in maternal morbidity in the United States. Further research is needed to understand the implications of treated chronic hypertension for the success of vaginal birth after cesarean delivery.

Effect of alternatively designed hospital birthing rooms on the rate of vaginal births: Multicentre randomised controlled trial Be-Up

BackgroundThere is limited research into the effects of the birth environment on birth outcomes. AimTo investigate the effect of a hospital birthing room designed to encourage mobility, self-determination and uptake of upright maternal positions in labour on the rate of vaginal births. MethodsThe multicentre randomised controlled trial Be-Up, conducted from April 2018 to May 2021 in 22 hospitals in Germany, included 3719 pregnant women with a singleton pregnancy in cephalic position at term. In the intervention birthing room, the bed was removed or covered in a corner of the room and materials were provided to promote upright maternal positions, physical mobility and self-determination. No changes were made in the control birthing room.The primary outcome was probability of vaginal births; secondary outcomes were episiotomy, perineal tears degree 3 and 4, epidural anaesthesia, “critical outcome of newborns at term”, and maternal self-determination (LAS). Analysis: intention-to-treat. FindingsThe rate of vaginal births was 89.1 % (95 % CI 87.5–90.4%; n = 1836) in the intervention group and 88.5 % (95 % CI 87.0–89.9 %; n = 1863) in the control group. The risk difference in the probability of vaginal birth was + 0.54 % (95 % CI − 1.49 % to 2.57 %), the odds ratio was 1.06 (95 % CI 0.86–1.30). Neither the secondary endpoints nor serious adverse events showed significant differences. Regardless of group assignment, there was a significant association between upright maternal body position and maternal self-determination. ConclusionThe increased vaginal birth rates in both comparison groups can be explained by the high motivation of the women and the staff.

Racial bias in cesarean decision-making

Category II fetal heart tracing noted during continuous external fetal monitoring is a frequent indication for cesarean delivery in the United States despite its somewhat subjective interpretation. Black patients have higher rates of cesarean delivery and higher rates for this indication. Racial bias in clinical decision-making has been demonstrated throughout medicine, including in obstetrics. We sought to examine if racial bias affects providers' decisions about cesarean delivery for an indication of category II fetal heart tracings. We constructed an online survey study consisting of 2 clinical scenarios of patients in labor with category II tracings. Patient race was randomized to Black and White; the vignettes were otherwise identical. Participants had the option to continue with labor or to proceed with a cesarean delivery at 3 decision points in each scenario. Participants reported their own demographics anonymously. This survey was distributed to obstetrical providers via email, listserv, and social media. Data were analyzed using chi-square tests at each decision point in the overall sample and in subgroup analyses by various participant demographics. A total of 726 participants contributed to the study. We did not find significant racial bias in cesarean delivery decision-making overall. However, in a scenario of a patient with a previous cesarean delivery, Fisher's exact tests showed that providers <40 years old (n=322; P=.01) and those with <10 years of experience (n=239; P=.050) opted for a cesarean delivery for Black patients more frequently than for White patients at the first decision point. As labor progressed in this scenario, the rates of cesarean delivery equalized across patient race. Younger providers and those with fewer years of clinical experience demonstrated racial bias in cesarean delivery decision-making at the first decision point early in labor. Providers did not show racial bias as labor progressed, nor in the scenario with a patient without a previous cesarean delivery. This bias may be the consequence of provider training with the Maternal-Fetal Medicine Unit Network Vaginal Birth After Cesarean Calculator, developed in 2007, and widely used to estimate the probability of successful vaginal birth after a cesarean delivery. This calculator used race as a predictive factor until it was removed in June 2021. Future studies should investigate if this bias persists following this change, while also focusing on interventions to address these findings.

Influencing factors and predictive model of live birth involving low-grade blastocyst frozen–thawed transfer: a retrospective study

BackgroundWhether only low-grade blastocysts should undergo freeze–thaw transfer during the in vitro fertilization/intracytoplasmic sperm injection cycle remains controversial; however, high-quality embryos cannot be obtained from some patients. Therefore, we aimed to identify factors that may affect the live birth.MethodsA total of 662 couples with only low-grade blastocysts who voluntarily accepted freeze–thaw blastocyst transfer at a single reproductive center over a 7-year period were followed-up. According to the outcome after transfer, they were divided into live birth group and failed pregnancy group. A nomogram was constructed for predicting live births.ResultsBaseline information and clinical treatment characteristics of patients in the two groups were comparable. Fifty-two of the 662 cycles (7.9%) resulted in live birth. Paternal age, maternal basal luteinizing hormone level, endometrial preparation scheme, and blastocyst development days were independent factors that affected low-grade blastocyst freeze–thaw transfer outcomes. The predictive model constructed based on these four factors presented favorable calibration and discriminatory abilities (area under the curve, 0.734; 95% confidence interval, 0.781–0.813).ConclusionsFor patients who exclusively underwent low-grade blastocyst freeze–thaw transfer, advanced paternal age and a high level of maternal basal luteinizing hormone adversely affected low-grade blastocyst freeze–thaw transfer outcomes. Artificial cycle preparation of the endometrium and day 5 blastocyst selection may improve the probability of live birth.

Increases in Obstetric Interventions and Changes in Gestational Age Distributions of U.S. Births.

Objective: To examine how changes in induction of labor (IOL) and cesarean deliveries between 1990 and 2017 affected gestational age distributions of births in the United States. Materials and Methods: Singleton first births were drawn from the National Vital Statistics System Birth Data for years 1990-2017. Separate analytic samples were created (1) by maternal race/ethnicity (Hispanic, non-Hispanic Black, non-Hispanic Asian, and non-Hispanic white), (2) by maternal age (15-19, 20-24, 25-29, 30-34, 35-39, 40-49), (3) by U.S. states, and (4) for women at low risk for obstetric interventions (e.g., age 20-34, no hypertension, no diabetes, no tobacco use). Gestational age was measured in weeks, and obstetric intervention status was measured as: (1) no IOL, vaginal delivery; (2) no IOL, cesarean delivery; and (3) IOL, all deliveries. The joint probabilities of birth at each gestational week by obstetric intervention status for years 1990-1991, 1998-1999, 2007-2008, and 2016-2017 were estimated. Results: Between 1990 and 2017, the percent of singleton first births occurring between 37 and 39 weeks of gestation increased from 38.5% to 49.5%. The changes were driven by increases in IOL and a shift in the use of cesarean deliveries toward earlier gestations. The changes were observed among all racial/ethnic groups and all maternal ages, and across all U.S. states. The same changes were also observed among U.S. women at low risk for interventions. Conclusion: Changes in gestational age distributions of U.S. births and their underlying causes are likely national-level phenomena and do not appear to be responding to increases in maternal risk for interventions.

Effect of state insurance mandates on racial/ethnic disparities in the utilization and outcomes of donor oocyte–assisted reproductive technologies

To characterize racial/ethnic disparities in donor oocyte-assisted reproductive technology (ART) nationwide and examine the impact of state insurance mandates on disparities in utilization and outcomes. Retrospective cohort study. Donor oocyte ART cycles in the United States (US). Women who underwent donor oocyte ART in 2014-2016, as reported to the Society for Assisted Reproductive Technology Clinic Outcome Reporting System. Race/ethnicity of oocyte recipients. Live birth through 1 or more donor oocyte ART cycles in 2014-2016 per recipient. We analyzed 44,033 donor ART cycles performed for 28,157 oocyte recipients, 99.2% (27,919/28,157) of whom were aged 25-54 years. Race/ethnicity data were reported for 61.4% (17,281/28,157) of the recipients. Among recipients aged 25-54 years with race data, 65.8% (11,264/17,128) identified as non-Hispanic White, whereas 58.9% were White among women aged 25-54 in the 2016 US census. In contrast, Black recipients comprised 8.3% of those aged 25-54 years with race data, compared with 13.7% nationwide. Among White recipients, 7.0% (791/11,356) lived in states with donor ART mandates (Massachusetts/New Jersey), compared with 6.5% (93/1,439) of Black recipients, 8.1% (108/1,335) of Hispanic recipients, and 5.8% (184/3,151) of Asian recipients. Black recipients had a higher median age and body mass index and were more likely to have uterine factor infertility. White recipients had the highest cumulative probability of live birth in the nonmandate (64.6%, 6,820/10,565) and mandate (69.5%, 550/791) states, followed by Asian recipients (nonmandate, 63.4% [1,881/2,967]; mandate, 65.2% [120/184]), Hispanic recipients (nonmandate, 60.5% [742/1,227]; mandate, 68.5% [74/108]), and Black recipients (nonmandate, 48.7% [655/1,346]; mandate, 48.4% [45/93]). The multivariable Poisson regression adjusting for donor's age and recipient's age, body mass index, nulliparity, history of recurrent pregnancy loss, diminished ovarian reserve, tubal factor and uterine factor infertility, prior ART treatment, use of preimplantation genetic testing, cumulative number of embryos transferred, use of blastocysts, and frozen-thawed transfers, demonstrated that Black recipients had a lower cumulative probability of a live birth than White recipients (relative risk [RR], 0.82; 95% confidence interval [CI], 0.77-0.87), as were Hispanic recipients (RR, 0.93; 95% CI, 0.89-0.99) and Asian recipients (RR, 0.96; 95% CI, 0.93-0.99). These disparities were not modified by state mandate for donor ART. State mandates for donor oocyte ART in their current forms are insufficient in decreasing racial/ethnic disparities.

Counterintuitive properties of evolutionary measures: A stochastic process study in cyclic population structures with periodic environments

Local environmental interactions are a major factor in determining the success of a new mutant in structured populations. Spatial variations in the concentration of genotype-specific resources change the fitness of competing strategies locally and thus can drastically change the outcome of evolutionary processes in unintuitive ways. The question is how such local environmental variations in network population structures change the condition for selection and fixation probability of an advantageous (or deleterious) mutant. We consider linear graph structures and focus on the case where resources have a spatial periodic pattern. This is the simplest model with two parameters, length scale and fitness scales, representing heterogeneity. We calculate fixation probability and fixation times for a constant population birth–death process as fitness heterogeneity and period vary. Fixation probability is affected by not only the level of fitness heterogeneity but also spatial scale of resources variations set by period of distribution T. We identify conditions for which a previously a deleterious mutant (in a uniform environment) becomes beneficial as fitness heterogeneity is increased. We observe cases where the fixation probability of both mutant and resident types are more than their neutral value, 1/N, simultaneously. This coincides with exponential increase in time to fixation which points to potential coexistence of resident and mutant types. Finally, we discuss the effect of the ‘fitness shift’ where the fitness function of two types has a phase difference. We observe significant increases (or decreases) in the fixation probability of the mutant as a result of such phase shift.

Towards an explainable clinical decision support system for large-for-gestational-age births.

A myriad of maternal and neonatal complications can result from delivery of a large-for-gestational-age (LGA) infant. LGA birth rates have increased in many countries since the late 20th century, partially due to a rise in maternal body mass index, which is associated with LGA risk. The objective of the current study was to develop LGA prediction models for women with overweight and obesity for the purpose of clinical decision support in a clinical setting. Maternal characteristics, serum biomarkers and fetal anatomy scan measurements for 465 pregnant women with overweight and obesity before and at approximately 21 weeks gestation were obtained from the PEARS (Pregnancy Exercise and Nutrition with smart phone application support) study data. Random forest, support vector machine, adaptive boosting and extreme gradient boosting algorithms were applied with synthetic minority over-sampling technique to develop probabilistic prediction models. Two models were developed for use in different settings: a clinical setting for white women (AUC-ROC of 0.75); and a clinical setting for women of all ethnicity and regions (AUC-ROC of 0.57). Maternal age, mid upper arm circumference, white cell count at the first antenatal visit, fetal biometry and gestational age at fetal anatomy scan were found to be important predictors of LGA. Pobal HP deprivation index and fetal biometry centiles, which are population-specific, are also important. Moreover, we explained our models with Local Interpretable Model-agnostic Explanations (LIME) to improve explainability, which was proven effective by case studies. Our explainable models can effectively predict the probability of an LGA birth for women with overweight and obesity, and are anticipated to be useful to support clinical decision-making and for the development of early pregnancy intervention strategies to reduce pregnancy complications related to LGA.

The sex preference for children in Europe: Children’s sex and the probability and timing of births

The preference for having children of a particular sex may be reflected in fertility behavior. For example, parents who want to have a son may be more likely to have another child if their firstborn child is female or if they have two female children. They

Does a free maternity policy in Kenya work? Impact and cost–benefit consideration based on demographic health survey data

This paper evaluates the overall effect of the Kenyan free maternity policy (FMP) on the main outcomes (early neonatal and neonatal deaths) and intermediate outcomes (delivery through Caesarean Section (CS), skilled birth attendance (SBA), birth in a public hospital and low birth weight (LBW)) using the 2014 Demographic Health Survey. We applied the difference-in-difference (DID) approach to compare births (to the same mothers) happening before and after the start of the policy (June 2013) and a limited cost–benefit analysis (CBA) to assess the net social benefit of the FMP. The probabilities of birth resulting in early neonatal and neonatal mortality are significantly reduced by 17–21% and 19–20%, respectively, after the FMP introduction. The probability of birth happening through CS reduced by 1.7% after implementing the FMP, while that of LBW birth is increased by 3.7% though not statistically significant. SBA and birth in a public facility did not moderate the policy’s effects on early neonatal mortality, neonatal mortality, and delivery through CS. They were not significant determinants of the policy effects on the outcomes. There is a significant causal impact of the FMP in reducing the probability of early neonatal and neonatal mortality, but not the delivery through CS. The FMP cost-to-benefit ratio was 21.22, and there were on average 4015 fewer neonatal deaths in 2013/2014 due to the FMP. The net benefits are higher than the costs; thus, there is a need to expand and sustainably fund the FMP to avert more neonatal deaths potentially.

Temporal trends and factors associated with preterm birth in Chile, 1992-2018.

An analytical study based on Chilean birth records obtained from the Department of Statistics and Health Information (DEIS) was conducted. This study aimed to evaluate temporal trends in preterm births by maternal age in Chile from 1990 to 2018. Results show that the preterm birth rate in 1992 was 5.0% and increased to 7.2% in 2018. The average annual percent change (AAPC) was 1.44. Age groups at the extremes (19 and under and 35 and over) presented the highest rates of preterm birth, both at the beginning and at the end of the study period. The latter group showed a smaller decrease at the beginning (1992 to 1995), with an annual percentage change (APC) of -3.00. The probability of preterm birth in both groups was higher compared to the 20-34 year old group. Although Chile boasts some of the best maternal and child health indicators in the region, repercussions associated with the current postponement of maternity - including preterm birth - must be monitored.

The Differential Impacts of Contingent Employment on Fertility: Evidence from Australia

Abstract Many studies have reported evidence of negative associations between fixed-term contract employment and fertility. With few exceptions, these studies assume that employment status is exogenous and thus results are likely biased. Furthermore, previous research has mostly not considered whether the effects of employment status on fertility might vary with other worker characteristics. We draw on nineteen years of data from the Household, Income and Labour Dynamics in Australia Survey to investigate the causal effect of contingent forms of employment (including both fixed-term and casual employment) on first births, and how that effect varies with selected worker characteristics. The issue of endogeneity is addressed through the use of instrumental variables estimation. Our main finding is that both fixed-term contracts and casual employment lead to a significantly lower probability of first births among men, with the effect of fixed-term contracts being almost as twice as large as the effect of casual employment. We also find that these negative fertility effects vary with workers’ education, occupational status, country of origin, age, and relationship status. In the case of women, one of the instruments fails to satisfy the exclusion restriction, suggesting endogeneity remains a concern when analyzing female fertility outcomes.

Confounding by Conception Seasonality in Studies of Temperature and Preterm Birth: A Simulation Study.

Seasonal patterns of conception may confound acute associations between birth outcomes and seasonally varying exposures. We aim to evaluate four epidemiologic designs (time-stratified case-crossover, time-series, pair-matched case-control, and time-to-event) commonly used to study acute associations between ambient temperature and preterm births. We conducted simulations assuming no effect of temperature on preterm birth. We generated pseudo-birth data from the observed seasonal patterns of birth in the United States and analyzed them in relation to observed temperatures using design-specific seasonality adjustments. Using the case-crossover approach (time-stratified by calendar month), we observed a bias (among 1,000 replicates) = 0.016 (Monte-Carlo standard error 95% CI: 0.015-0.018) in the regression coefficient for every 10°C increase in mean temperature in the warm season (May-September). Unbiased estimates obtained using the time-series approach required accounting for both the pregnancies-at-risk and their weighted probability of birth. Notably, adding the daily weighted probability of birth from the time-series models to the case-crossover models corrected the bias in the case-crossover approach. In the pair-matched case-control design, where the exposure period was matched on gestational window, we observed no bias. The time-to-event approach was also unbiased but was more computationally intensive than others. Most designs can be implemented in a way that yields estimates unbiased by conception seasonality. The time-stratified case-crossover design exhibited a small positive bias, which could contribute to, but not fully explain, previously reported associations.

Predicted probabilities of live birth following assisted reproductive technology using United States national surveillance data from 2016 to 2018

As the use of invitro fertilization continues to increase in the United States, up-to-date models that estimate cumulative live birth rates after multiple oocyte retrievals and embryo transfers (fresh and frozen) are valuable for patients and clinicians weighing treatment options. This study aimed to develop models that generate predicted probabilities of live birth in individuals considering invitro fertilization based on demographic and reproductive characteristics. Our population-based cohort study used data from the National Assisted Reproductive Technology Surveillance System 2016 to 2018, including 196,916 women who underwent 207,766 autologous embryo transfer cycles and 25,831 women who underwent 36,909 donor oocyte transfer cycles. We used data on autologous invitro fertilization cycles to develop models that estimate a patient's cumulative live birth rate after all embryo transfers (fresh and frozen) within 12 months after 1, 2, and 3 oocyte retrievals in new and returning patients. Among patients using donor oocytes, we estimated the cumulative live birth rate after their first, second, and third embryo transfers. Multinomial logistic regression models adjusted for age, prepregnancy body mass index (imputed for 18% of missing values), parity, gravidity, and infertility diagnoses were used to estimate the cumulative live birth rate. Among new and returning patients undergoing autologous invitro fertilization, female age had the strongest association with cumulative live birth rate. Other factors associated with higher cumulative live birth rates were lower body mass index and parity or gravidity ≥1, although results were inconsistent. Infertility diagnoses of diminished ovarian reserve, uterine factor, and other reasons were associated with a lower cumulative live birth rate, whereas male factor, tubal factor, ovulatory disorders, and unexplained infertility were associated with a higher cumulative live birth rate. Based on our models, a new patient who is 35 years old, with a body mass index of 25 kg/m2, no previous pregnancy, and unexplained infertility diagnoses, has a 48%, 69%, and 80% cumulative live birth rate after the first, second, and third oocyte retrieval, respectively. Cumulative live birth rates are 29%, 48%, and 62%, respectively, if the patient had diminished ovarian reserve, and 25%, 41%, and 52%, respectively, if the patient was 40 years old (with unexplained infertility). Very few recipient characteristics were associated with cumulative live birth rate in donor oocyte patients. Our models provided estimates of cumulative live birth rate based on demographic and reproductive characteristics to help inform patients and providers of a woman's probability of success after invitro fertilization.

What is the optimal GnRH antagonist protocol for ovarian stimulation during ART treatment? A systematic review and network meta-analysis.

Several GnRH antagonist protocols are currently used during COS in the context of ART treatments; however, questions remain regarding whether these protocols are comparable in terms of efficacy and safety. A systematic review followed by a pairwise and network meta-analyses were performed. The systematic review and pairwise meta-analysis of direct comparative data according to the PRISMA guidelines evaluated the effectiveness of different GnRH antagonist protocols (fixed Day 5/6 versus flexible, ganirelix versus cetrorelix, with or without hormonal pretreatment) on the probability of live birth and ongoing pregnancy after COS during ART treatment. A frequentist network meta-analysis combining direct and indirect comparisons (using the long GnRH agonist protocol as the comparator) was also performed to enhance the precision of the estimates. The systematic literature search was performed using Embase (Ovid), MEDLINE (Ovid), Cochrane Central Register of Trials (CENTRAL), SCOPUS and Web of Science (WOS), from inception until 23 November 2021. The search terms comprised three different MeSH terms that should be present in the identified studies: GnRH antagonist; assisted reproduction treatment; randomized controlled trial (RCT). Only studies published in English were included. The search strategy resulted in 6738 individual publications, of which 102 were included in the systematic review (corresponding to 75 unique studies) and 73 were included in the meta-analysis. Most studies were of low quality. One study compared a flexible protocol with a fixed Day 5 protocol and the remaining RCTs with a fixed Day 6 protocol. There was a lack of data regarding live birth when comparing the flexible and fixed GnRH antagonist protocols or cetrorelix and ganirelix. No significant difference in live birth rate was observed between the different pretreatment regimens versus no pretreatment or between the different pretreatment protocols. A flexible GnRH antagonist protocol resulted in a significantly lower OPR compared with a fixed Day 5/6 protocol (relative risk (RR) 0.76, 95% CI 0.62 to 0.94, I2 = 0%; 6 RCTs; n = 907 participants; low certainty evidence). There were insufficient data for a comparison of cetrorelix and ganirelix for OPR. OCP pretreatment was associated with a lower OPR compared with no pretreatment intervention (RR 0.79, 95% CI 0.69 to 0.92; I2 = 0%; 5 RCTs, n = 1318 participants; low certainty evidence). Furthermore, in the network meta-analysis, a fixed protocol with OCP resulted in a significantly lower OPR than a fixed protocol with no pretreatment (RR 0.84, 95% CI 0.71 to 0.99; moderate quality evidence). The surface under the cumulative ranking (SUCRA) scores suggested that the fixed protocol with no pretreatment is the antagonist protocol most likely (84%) to result in the highest OPR. There was insufficient evidence of a difference between fixed/flexible or OCP pretreatment/no pretreatment interventions regarding other outcomes, such as ovarian hyperstimulation syndrome and miscarriage rates. Available evidence, mostly of low quality and certainty, suggests that different antagonist protocols should not be considered as equivalent for clinical decision-making. More trials are required to assess the comparative effectiveness of ganirelix versus cetrorelix, the effect of different pretreatment interventions (e.g. progestins or oestradiol) or the effect of different criteria for initiation of the antagonist in the flexible protocol. Furthermore, more studies are required examining the optimal GnRH antagonist protocol in women with high or low response to ovarian stimulation.

Correlation of Qualitative Alpha1-microglobulin, Values of Interleukin 6, Cervicometry and Cervical Infection in Pregnant Women with Symptoms of Preterm Birth.

One of the problems in modern obstetrics is how to identify and select pregnant women who are most likely to give premature birth. In the last ten years, due to false-positive test results, i.e., tests with low positive predictive values, there is an increase in unnecessary hospitalization days as well as unnecessary therapy. The probability of preterm birth is 25% in a population of pregnant women with symptoms of preterm birth. The aim was to analyze diagnostic accuracy of tests for the purpose of predicting premature births in< 37th and <34th week of pregnancy.Incidence of preterm births in < 37th week of pregnancy was 28%, while the incidence of preterm births up until 34th week of pregnancy, was < 8%. We included two groups of pregnant women in a prospective study; one group with the symptoms of threatening preterm birth between 22nd and 37th week of pregnancyand the other one of the same gestation period with no symptoms. Each pregnant woman underwent test for placental alphamicroglobulin-1, cervical length screening, cervical sampling for microbiological analysis, blood sampling for IL6 and CRP analysis. There were 16% of preterm births, up until 7 days from hospitalization, and they were all PAMG-1 positive; There is 75% of preterm births if PAMG-1 is positive with cervical length under 25mm. Combining tests, we reached the best predictive accuracy with positive PAMG-1 test, cervical length under 15mm along with the increase of CRP values above 15.96%. Total number of hospitalization days was 29% with preterm births up to 71% with full term births regardless the symptomatology, which justifies further studies towards releasing the pressure from the health care system and from doctors as well in the process of reaching a decision on treatment of pregnant women with the signs of preterm birth.

Anti-β2-glycoprotein I antibody maybe a novel biomarker of spontaneous preterm birth.

Spontaneous preterm birth is challenging to prevent. Only few predictors of spontaneous preterm birth risk have been reported, and further studies on spontaneous preterm birth should be conducted to reduce the number of cases. The aim of the present study was to explore if anti-β2-glycoprotein I antibody can be used to predict the risk of spontaneous preterm birth, and its clinical value in assessing the risk of spontaneous preterm birth. A total of 302 pregnant women who had delivered between January 2019 and December 2021 were enrolled into the study. The subjects were assigned to the case group (28-33+6weeks, n = 41; 34-36+6weeks, n = 96) and control group (37-42weeks, n = 165) according to the gestational period. The age, body mass index, and gestational days of the two groups were recorded. Blood samples were collected and the levels of anti-β2-glycoprotein I antibody, white blood cell, red blood cell, hemoglobin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, urea, creatinine, glucose, triglyceride, and total cholesterol were evaluated. Pregnant women diagnosed with sPTB that met the standards after evaluation by the clinician were included in the study. The level of anti-β2-glycoprotein I antibody was higher in case group than in the control group [(23.93 ± 8.11)Ru/mL vs (11.50 ± 5.33)Ru/mL]. The results showed that anti-β2-glycoprotein I antibody was an independent risk factor for spontaneous preterm birth. The area under ROC curve of anti-β2-glycoprotein I antibody to predict spontaneous preterm birth was 0.8875 (95%CI 0.8443-0.9307). The highest predicted value of anti-β2-glycoprotein I antibody was 16.49Ru/ml. Anti-β2-glycoprotein I antibody has a high clinical significance and can be used by clinicians to evaluate the probability of spontaneous preterm birth.

Fresh vs. frozen embryo transfer: new approach to minimize the limitations of using national surveillance data for clinical research

To assess the benefit of frozen vs. fresh elective single embryo transfer using traditional and novel methods of controlling for confounding. Retrospective cohort study using data from the National Assisted Reproductive Technology Surveillance System. Not applicable. A total of 44,750 women aged 20-35 years undergoing their first lifetime oocyte retrieval and embryo transfer in 2016-2017, who had ≥4 embryos cryopreserved. Fresh elective single embryo transfer and frozen elective single embryo transfer. The primary outcome was a singleton live birth. Secondary outcomes included rates of total live birth (singleton plus multiple gestations), twin live birth, clinical intrauterine gestation, total pregnancy loss, biochemical pregnancy, and ectopic pregnancy. Outcomes for infants included gestational age at delivery, birth weight, and being small for gestational age. The eligibility criteria were met by 6,324 fresh and 2,318 frozen cycles. Patients undergoing fresh and frozen transfer had comparable mean age (30.69 [standard deviation {SD} 0.08] years vs. 31.06 [SD 0.08] years) and body mass index (24.76 [SD 0.20] vs. 25.65 [SD 0.15]); however, women in the frozen cohort created more embryos (8.1 [SD 0.12] vs. 6.8 [SD 0.08]). Singleton live birth rates in the fresh vs. frozen groups were 51.4% vs. 48.8% (risk ratio 1.05; 95% confidence interval [CI], 1.00-1.10). After adjustment with a log-linear regression model and propensity score analysis, the difference in singleton live birth rates remained nonsignificant (adjusted risk ratio, 1.05; 95% CI, 0.97-1.14 and 1.02; 95% CI, 0.96-1.08, respectively). A novel dynamical model confirmed inherent fertility (probability of ever achieving a pregnancy) was balanced between groups (odds ratio, 1.23; 95% CI 0.78-1.95]). The per-cycle probability of singleton live birth was not different between groups (odds ratio 1.11 [95% CI 0.94-1.3]). In this retrospective cohort study of fresh vs. frozen elective single embryo transfer, there was no statistically significant difference in singleton live birth rate after adjustment using log-linear models and propensity score analysis. The successful application of a novel dynamical model, which incorporates multiple assisted reproductive technology cycles from the same woman as a surrogate for inherent fertility, offers a novel and complementary perspective for assessing interventions using national surveillance data.

Maternal health intervention and sex ratios: evidence from the Village Midwife Program in Indonesia

AbstractIn about last three decades, many developing countries have experienced a large decline in maternal mortality rates. Global initiatives leading to better maternal health policies may have contributed to this decline. In this paper, we investigate whether maternal health intervention also improves the fetal survival rate. For this purpose, we consider the Village Midwife Program in Indonesia, which was launched in 1989 as a part of the safe motherhood strategy. Using the Indonesian Family Life Survey (IFLS), we investigate the impact of midwives on fetal survival rate in terms of a change in the likelihood of a live birth being male. Our results show that the provision of a midwife in a community increases the probability of a live birth being male by about 3 percentage points. Greater antenatal care, skilled birth-attendance, and an improvement in nutrition among reproductive-age women—in terms of greater BMI—are the likely pathways. We do not find the results to be driven by pre-treatment trends, and they remain robust to a number of checks.