Higher Rates Of Preterm Birth Research Articles

Long-term outcomes for children conceived by assisted reproductive technology

Worldwide, more than 10 million children have been born after Assisted Reproduction Technology (ART) and comprised up to 7.9% of children born in Europe and up to 5.1 % of children born in the US in 2018 (1, 2). The short-term outcome for children born after ART is well-known from numerous publications, with higher rates of preterm birth and low birth weight in children born after fresh embryo transfer and higher rates of large for gestational age and high birth weight in children born after frozen embryo transfer compared to children born after spontaneous conception (3, 4). Higher rates of birth defects in children born after ART have also been shown consistently over time (5). Studies on long-term health outcomes after ART are scarcer but suggest an increased risk of altered blood pressure and cardiovascular function in children born after ART. In this review we summarize long-term health outcomes in children born after ART and discuss if the increased health risks are associated with intrinsic maternal or paternal factors related to sub fertility or to the ART treatments per se. Finally, we speculate where the future will bring us with regards to ART treatment strategies and safety of the mother and child.

Short Interpregnancy Interval Following a Multifetal Pregnancy: Maternal and Neonatal Outcomes

To evaluate the maternal and neonatal outcomes of women with short interpregnancy intervals (IPI < 6 months) following a multifetal pregnancy. A multicenter retrospective cohort study of women with an index multifetal delivery and a subsequent singleton gestation between 2005 and 2021. The obstetrical outcomes of pregnancies following short IPI (<6 months) were compared to those with an IPI of 18-48 months. Additional analyses were also conducted for the other IPI groups: 7-17 months, and longer than 49 months, while women with an IPI of 18-48 months served as the reference group. The primary outcome was preterm birth (<37 weeks) rate. Secondary outcomes were other adverse maternal and neonatal outcomes. Univariate and multiple logistic regression analyses were performed. Overall, 2514 women had a primary multifetal delivery with a subsequent singleton gestation at our medical centers; 160 (6.4%) had a short IPI, and 1142 (45.4%) had an optimal IPI. Women with a singleton gestation following a short IPI were younger, with lower rates of previous cesarean and fertility treatments. Women in the short IPI group had significantly higher rates of preterm birth <37 weeks, anemia (Hb < 11 gr%) on admission to the delivery room, and placental abruption. Multivariable logistic regression analysis demonstrated that short IPI is associated with an increased risk for preterm birth (aOR 2.39, 95% CI 1.12-5.11, p = 0.03). Short IPI following a multifetal gestation is associated with an increased risk for preterm birth in subsequent singleton pregnancy.

The Role of Cerclage in Subsequent Pregnancy following Previable Prelabor Rupture of Membranes.

This study aimed to ascertain the outcomes associated with a cervical cerclage among individuals with a history of previable prelabor rupture of membranes (PROM). This study was a retrospective cohort study conducted at a single tertiary center between 2011 and 2021. We included individuals with a history of previable (before 24 weeks) PROM and the subsequent viable pregnancy. Women with multifetal gestation, preterm birth (PTB) or cerclage in previous gestation, or abdominal cerclage after trachelectomy were excluded. Primary outcome was PTB rate (delivery <37 weeks). Recurrence of preterm PROM and adverse composite maternal and neonatal outcomes (CMO and CNO) were evaluated as secondary outcomes. CMO included any of the following: suspected chorioamnionitis, endometritis, red blood cell transfusion, uterine rupture, unplanned hysterectomy, or death. CNO included any of the following: previable PTB (<24 weeks of gestation), bronchopulmonary dysplasia, grade 3 or 4 intraventricular hemorrhage, necrotizing enterocolitis, mechanical ventilation, seizures, hypoxic ischemic encephalopathy, or death. During the study period, 118 individuals had a history of previable PROM and a documented subsequent pregnancy, out of which 74 (62.7%) met inclusion criteria. Nineteen (25.7%) of eligible individuals underwent a cerclage for prior previable PROM and were compared with controls (n = 55, 74.3%). Women who underwent a cerclage had higher rates of PTB < 37 weeks (63.2 vs. 10.9%, p < 0.001; odds ratio [OR]: 14.00, 95% confidence interval [CI]: 3.97-49.35) and < 34 weeks (21.1 vs. 3.6%, p = 0.03; OR: 7.07, 95% CI: 1.18-42.39) compared with those without cerclage. Furthermore, recurrent preterm PROM and previable PTB rates were higher among patients who underwent cerclage. The survival curve further indicated that individuals with cerclage delivered earlier. CMO and CNO rates were similar in those with and without cerclage. Cerclage placement in individuals with prior previable PROM was associated with higher rates of recurrent preterm PROM and PTB. · The management of individuals in a subsequent pregnancy following previable PROM is a conundrum.. · Cerclage following previable PROM is associated with higher rates of recurrent preterm PROM and PTB.. · Composite maternal and neonatal outcome rates were similar in those with and without cerclage..

The course of infection with the Delta variant of COVID-19 in pregnancy: Analysis of clinical, laboratory, and neonatal outcomes.

This study aims to examine the effects of infection with the Delta variant of COVID-19 on the clinical course, laboratory parameters, and neonatal outcomes in pregnant women. A total of 96 pregnant women who tested positive for the Delta variant of COVID-19 were retrospectively examined. The pregnant women were divided into three groups as follows: asymptomatic, non-severe, and severe. Age, obstetric history, symptoms and findings, blood tests, medication and vaccination history, clinical course, and perinatal outcomes of pregnant women were analyzed. Pregnant women who tested positive for the Delta variant of COVID-19 had an ICU admission rate of 9.4% and a mortality rate of 5.2%. Pregnant women in the severe disease group had significantly higher rates of preterm birth and cesarean section compared with the non-severe and asymptomatic group. Pregnant women in the severe group had high c-reactive protein (CRP) levels at the time of admission. White blood cell (WBC) and procalcitonin levels increased in clinical follow-up in pregnant women in the severe group. The Delta variant of COVID-19 was found to increase mortality rates in pregnant women compared to pre-Delta variants of COVID-19. In pregnant women infected with the Delta variant of COVID-19, advanced gestational age at diagnosis, high CRP, WBC, and procalcitonin levels were significantly correlated with poor prognosis. Pregnant women infected with the Delta variant of COVID-19 had an increased risk for preterm delivery and cesarean section in the presence of severe disease. Although newborns of women with severe disease were found to have significantly higher rates of ICU admission, there was no significant difference in neonatal mortality rates. We recommend close monitoring of CRP, WBC, and procalcitonin levels in addition to symptoms in pregnant women infected with the Delta variant of COVID-19 in the third trimester.

Pregnancy-associated gynecological cancer in New South Wales, Australia 1994-2013: A population-based historical cohort study.

Pregnancy-associated gynecological cancer (PAGC) refers to cancers of the ovary, uterus, fallopian tube, cervix, vagina, and vulva diagnosed during pregnancy or within 12 months postpartum. We aimed to describe the incidence of, and perinatal outcomes associated with, invasive pregnancy-associated gynecological cancer. We conducted a population-based historical cohort study using linked data from New South Wales, Australia. We included all women who gave birth between 1994 and 2013, with a follow-up period extending to September 30, 2018. Three groups were analyzed: a gestational PAGC group (women diagnosed during pregnancy), a postpartum PAGC group (women diagnosed within 1 year of giving birth), and a control group (women with control diagnosis during pregnancy or within 1 year of giving birth). We used generalized estimation equations to compare perinatal outcomes between study groups. There were 1786 137 deliveries during the study period; 70 women were diagnosed with gestational PAGC and 191 with postpartum PAGC. The incidence of PAGC was 14.6/100 000 deliveries and did not change during the study period. Women with gestational PAGC (adjusted odds ratio [aAOR] 6.81, 95% confidence interval [CI] 2.97-15.62) and with postpartum PAGC (aOR 2.65, 95% CI 1.25-5.61) had significantly increased odds of a severe maternal morbidity outcome compared with the control group. Babies born to women with gestational PAGC were more likely to be born preterm (aOR 3.11, 95% CI 1.47-6.59) and were at increased odds of severe neonatal complications (aOR 3.47, 95% CI 1.45-8.31) compared with babies born to women without PAC. The incidence of PAGC has not increased over time perhaps reflecting, in part, the effectiveness of cervical screening and early impacts of human papillomavirus vaccination programs in Australia. The higher rate of preterm birth among the gestational PAGC group is associated with adverse outcomes in babies born to these women.

Prenatal exposure to persistent and non-persistent chemical mixtures and associations with adverse birth outcomes in the Atlanta African American Maternal-Child Cohort.

African Americans (AAs) experience higher rates of preterm birth and fetal growth restriction relative to other pregnant populations. Differential in utero exposure to environmental chemicals may partially explain these health disparities, as AAs are disproportionately exposed to environmental hazards. We examined the individual and mixture effects of non-persistent chemicals and persistent organic pollutants (POPs) on gestational age at birth and birthweight for gestational age z-scores within a prospective cohort of pregnant AAs. First-trimester serum and urine samples obtained from participants within the Atlanta African American Maternal-Child cohort were analyzed for 43 environmental chemicals, including per-and polyfluoroalkyl substances (PFAS), polybrominated diphenyl ethers (PBDEs), organochlorine pesticides, pyrethroid insecticides, phthalates, bisphenol A, nicotine, and the primary metabolite of delta-9-tetrahydrocannabinol. Linear regression was used to estimate individual associations between chemicals and gestational age and birthweight z-scores (N ranging from 107 to 523). Mixture associations were estimated using quantile g-computation, principal component (PC) analyses, and hierarchical Bayesian kernel machine regression among complete cases (N = 86). Using quantile g-computation, increasing all chemical exposures by one quantile was modestly associated with a reduction in gestational age (mean change per quartile increase = -0.47, 95% CI = -1.56, 0.61) and birthweight z-scores (mean change per quartile increase = -0.49, 95% CI = -1.14, 0.15). All PCs were associated with a reduction in birthweight z-scores; associations were greatest in magnitude for the two PCs reflecting exposure to combined tobacco, insecticides, PBDEs, and phthalates. In single pollutant models, we observed inconsistent and largely non-significant associations. We conducted multiple targeted exposure assessment methods to quantify levels of environmental chemicals and leveraged mixture methods to quantify their joint effects on gestational age and birthweight z-scores. Our findings suggest that prenatal exposure to multiple classes of persistent and non-persistent chemicals is associated with reduced gestational age and birthweight z-scores in AAs. African Americans (AAs) experience higher rates of preterm birth and fetal growth restriction relative to other pregnant populations. Differential in utero exposure to environmental chemicals may partially explain these health disparities, as AAs are disproportionately exposed to environmental hazards. In the present study, we analyzed serum and urine samples for levels of 43 environmental chemicals. We used quantile g-computation, principal component analysis, and BKMR to assess associations between chemical exposure mixtures and adverse birth outcomes. Our findings suggest that prenatal exposure to multiple classes of chemicals is associated with reduced birthweight z-scores, a proxy for fetal growth, in AAs.

Maternal Prepregnancy Obesity Affects Foetal Growth, Birth Outcome, Mode of Delivery, and Miscarriage Rate in Austrian Women

The increasing obesity rates among women of reproductive age create a major obstetrical problem as obesity during pregnancy is associated with many complications, such as a higher rate of caesarean sections. This medical record-based study investigates the effects of maternal prepregnancy obesity on newborn parameters, birth mode, and miscarriage rate. The data of 15,404 singleton births that had taken place between 2009 and 2019 at the public Danube Hospital in Vienna were enrolled in the study. Newborn parameters are birth weight, birth length, head circumference, APGAR scores, as well as pH values of the arterial and venous umbilical cord blood. In addition, maternal age, height, body weight at the beginning and the end of pregnancy, and prepregnancy body mass index (BMI) (kg/m2) have been documented. The gestational week of birth, the mode of delivery, as well as the number of previous pregnancies and births, are included in the analyses. Birth length, birth weight, and head circumference of the newborn increase with increasing maternal BMI. Furthermore, with increasing maternal weight class, there tends to be a decrease in the pH value of the umbilical cord blood. Additionally, obese women have a history of more miscarriages, a higher rate of preterm birth, and a higher rate of emergency caesarean section than their normal-weight counterparts. Consequently, maternal obesity before and during pregnancy has far-reaching consequences for the mother, the child, and thus for the health care system.

Cardiac and obstetric outcomes of pregnancies for women after cardiotoxic therapy in childhood: a single center observational study

BackgroundChildhood cancer survivors (CCS) are at increased risk of cardiomyopathy during pregnancy if they have prior cardiotoxic exposure. Currently, there is no consensus on the necessity, timing and modality of cardiac monitoring during and after pregnancy. Therefore, we examined cardiac function using contemporary echocardiographic parameters during pregnancy in CCS with cardiotoxic treatment exposure, and we observed obstetric outcomes in CCS, including in women without previous cardiotoxic treatment exposure.MethodA single-center retrospective cohort study was conducted among 39 women enrolled in our institution’s cancer survivorship outpatient clinic. Information on potential cardiotoxic exposure in childhood, cancer diagnosis and outcomes of all pregnancies were collected through interviews and review of health records. Echocardiographic exams before and during pregnancy were retrospectively analyzed for left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) if available. The primary outcomes were (i) left ventricular dysfunction (LVD) during pregnancy, defined as LVEF < 50% or a decline of ≥ 10% in LVEF below normal (< 54%), and (ii) symptomatic heart failure (HF). Rate of obstetric and fetal complications was compared to the general population through the national perinatal registry (PERINED).ResultsAll pregnancies (91) of 39 women were included in this study. The most common malignancy was leukemia (N = 17, 43.6%). In 22 patients, echocardiograms were retrospectively analyzed. LVEFbaseline was 55.4 ± 1.2% and pre-existing subnormal LVEF was common (7/22, 31.8/%). The minimum value of LVEF during pregnancy was 3.8% lower than baseline (p = 0.002). LVD occurred in 9/22 (40.9%) patients and HF was not observed. When GLS was normal at baseline (< -18.0%; N = 12), none of the women developed LVD. Nine of out ten women with abnormal GLS at baseline developed LVD later in pregnancy. In our cohort, the obstetric outcomes seemed comparable with the general population unless patients underwent abdominal irradiation (N = 5), where high rates of preterm birth (only 5/18 born at term) and miscarriage (6/18 pregnancies) were observed.ConclusionOur study suggests that women with prior cardiotoxic treatment have a low risk of LVD during pregnancy if GLS at baseline was normal. Pregnancy outcomes are similar to the healthy population except when patients underwent abdominal irradiation.

A three-year audit of pregnancy outcomes in women with pulmonary hypertension admitted to the high-risk obstetric unit at Inkosi Albert Luthuli Central Hospital, KwaZulu-Natal, South Africa.

The aim of this study was to describe the profile and outcomes of pregnancies in women with pulmonary hypertension in South Africa. A retrospective study was undertaken at a state-subsidised hospital. Data were analysed using SPSS. Descriptive statistics were used to summarise categorical variables. Central tendency and dispersion of data were measured using means and standard deviations for normally distributed variables and medians and interquartile ranges for skewed variables. A p-value less than 0.05 was considered statistically significant. Of a cohort of 185 women, 86.3% had pulmonary hypertension secondary to left heart disease. The median age of the cohort was 28 years (interquartile range 23-33) with 37.8% being HIV infected and 59% having mild pulmonary hypertension. Frequencies of deaths, intensive care unit admissions and cardiac failure events increased with increasing severity of pulmonary hypertension (p < 0.001). Women with more severe pulmonary hypertension had higher rates of preterm births (p < 0.001). Adverse pregnancy outcomes were concentrated in women with moderate-to-severe pulmonary hypertension.

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.

Neonatal Outcomes for Women at Risk of Preterm Delivery Given Half Dose Versus Full Dose of Antenatal Betamethasone: A Randomized, Multicentre, Double-blind, Placebo-Controlled, Non-inferiority Trial

ABSTRACT Antenatal corticosteroid administration to women at risk of preterm delivery is recommended worldwide because of their effectiveness in preventing respiratory distress syndrome, as well as in reducing the rate of necrotizing enterocolitis, intraventricular hemorrhage, and neonatal death in preterm infants. However, the current usual dosage regimen of 2 injections of 12 mg of betamethasone (BMZ) 24 hours apart originated from preclinical experiments in the 1960s and has not been investigated in randomized clinical trials. These authors therefore designed a randomized trial for investigating whether a half dose of BMZ would be as effective as the standard full-dose regimen. The primary outcome was the need for exogenous surfactant within the first 48 hours of life. Secondary outcomes included the incidence and severity of respiratory disease, such as respiratory distress syndrome. This randomized, multicenter, double-blind placebo-controlled, noninferiority study was conducted in 37 perinatal centers in France. Pregnant women 18 years or older with singleton pregnancies at risk of delivery preterm (and already treated with dose 1 of antenatal BMZ before 32 weeks' gestation) were eligible to participate. Exclusion criteria included multiple pregnancy, having previously received full-dose antenatal corticosteroids, 4 cm or greater cervical dilation, cervical length of 20 mm or greater, fetal major malformations or chromosomal aberrations, or being unable to communicate fluently in French. Upon hospital admission after the first BMZ injection, women were provided information about the trial, and those who agreed were randomly assigned in a 1:1 ratio to receive either a saline placebo or the second intramuscular BMZ dose. A total of 3196 women participated, with 1597 in the half-dose group and 1599 in the full-dose group. In all, 30 fetuses were stillborn, 16 neonates were lost to follow-up, and 9 neonates died before evaluation, leaving 1567 neonates in the half-dose group and 1574 neonates in the full-dose group. In the intention-to-treat analysis, the primary outcome occurred in 313 (20%) of neonates in the half-dose group and 276 (17.5%) in the full-dose group (risk difference, 2.4%; 95% confidence interval [CI], 0.3–5.2); thus, noninferiority was not shown. The per-protocol analysis also did not show noninferiority (risk difference, 2.2%; 95% CI, −0.6 to 5.1). There were no differences in the rates of neonatal death, grade 3 to 4 intraventricular hemorrhage, stage ≥2 necrotizing enterocolitis, severe retinopathy of prematurity, or bronchopulmonary dysplasia. Between the 2 groups, all other secondary prematurity-associated outcomes were also similar. Strengths of the study included its large sample size and low loss-to-follow-up rate (0.5%), as well as consistent perinatal management approach through the Groupe de Recherche en Obstetrique et Gynecologie. However, the study also had limitations, such as the potential for the primary outcome to be considered a short-term surrogate only partially reflecting the overall severity of neonatal illness. The rate of the primary outcome observed in the study was also 2.5% lower than anticipated, which the authors attribute to the numbers of deliveries that occurred before 32 weeks' gestation and beyond 7 days following treatment. The number of births occurring within this window of time may limit the ability to demonstrate true differences between the 2 groups, meaning that the authors could not rule out the possibility of half-doses being inferior given higher preterm birth rates. In addition, long-term evaluation of the infants involved in the study via a follow-up evaluation at 5 years of age will be critical to determining the overall effect of BMZ dose reduction on neurological development. The authors concluded that this trial indicated the half-dose antenatal BMZ regimen did not meet criterion for noninferiority when compared with the currently recommended regimen in singleton pregnancies for preventing respiratory distress syndrome that requires exogenous intratracheal surfactant.

Nausea and vomiting of pregnancy beyond the first trimester and the risk of preterm birth

Although most pregnant persons with nausea and vomiting of pregnancy (NVP) have symptoms that improve after the first trimester, approximately 20% experience NVP later in gestation. Little is known about pregnancy outcomes among these individuals. We aimed to investigate pregnancy outcomes among those with NVP after the first trimester. This is a secondary analysis of 9117 nulliparas from the NuMoM2b cohort who underwent NVP assessment with the Pregnancy-Unique Quantification of Emesis (PUQE) scale at three study visits; “V1” at 12.5±2.7 weeks, “V2” at 19.4±2.5 weeks, and “V3” at 28.0±3.2 weeks. Scores ranged 3-15 and were classified as having no NVP symptoms (PUQE score=3), mild (4-6) or moderate/severe (≥ 7) NVP at each visit. Chi-square analyses were used to compare the rate of adverse pregnancy outcomes (APO); small for gestational age, gestational hypertension, stillbirth, gestational diabetes, preterm birth (PTB) < 34 weeks, PTB < 37 weeks, across NVP categories at each study visit. Separate logistic regression models were used to estimate the association between degree of NVP at each visit and the odds of PTB < 37 weeks – adjusted for covariates (age, body mass index, race/ethnicity, smoking, gestational hypertension, depression). A separate sensitivity analysis was performed with additional adjustment for rate of gestational weight gain (GWG) per week. Degree of NVP at V1 and V3 was not associated with APO. There was a higher rate of PTB < 37 weeks in those with mild (10.1%) and moderate/severe NVP (13.3% ) versus having no NVP (8.2%) in V2 (χ2=13.8, p=0.001) (Table 1). On adjusted analysis, there was a marginally higher odds of PTB < 37 weeks among those with mild NVP at V2 (OR 1.21, 95% CI 1.00 to 1.47, p=0.050) and significantly higher odds with moderate/severe NVP at V2 (OR 1.60, 95% CI 1.09 to 2.36, p=0.017) versus having no NVP. This relationship was strengthened after adding GWG as a covariate (OR 1.85, 95% CI: 1.20 to 2.86, p=0.005). Moderate/severe NVP in mid-gestation may be associated with a higher risk of PTB.

IMPACT OF COVID-19 ON PREGNANCY (REVIEW)

SARS-CoV-2 infection during pregnancy is associated with a number of adverse pregnancy outcomes, including preeclampsia, preterm birth, and stillbirth, especially among pregnant women with severe COVID-19. Several fetal complications such as early pregnancy loss, delivery of a premature fetus, preeclampsia, fetal death, vertical transmission, intrauterine growth retardation, and congenital structural anomalies in association with COVID-19 disease have been investigated.Тo review on the fetal adverse outcome that is likely to occur during COVID-19 disease. The fetal detrimental outcomes that have been widely studied in the literature include preterm birth, stillbirth, vertical transmission. The evidence in the literature supports that there is a higher rate of preterm birth and stillbirth in women who tested positive for SARS-CoV-2 but their association with the disease is not completely clear. Furthermore, the emergence of other possible outcomes is not conclusively stated. Hence more studies are required to establish their association with COVID-19 disease to decrease and mitigate the risk of detrimental fetal outcomes through early interventions and preventive measures

Risk Factors of Preterm Birth in Okinawa Prefecture, the Southernmost Island Prefecture of Japan.

A high rate of preterm birth has been reported in Okinawa Prefecture, the southernmost island prefecture of Japan. Hence, this study aimed to identify the risk factors for preterm birth in this prefecture. This retrospective study included data from January 2013 to December 2019 from three facilities in Okinawa Prefecture. Of 13,468 cases of preterm birth at ≥ 22 weeks of gestation, 11,868 were included in this study. Stillbirth and multiparity cases were excluded. First, we compared the overall preterm and full-term birth groups by categorizing the patient background, obstetric, and fetal risk factors. Further, we categorized preterm births into three groups (22-27, 28-33, and 34-36 weeks of gestation) and examined patient background factors to identify potential risk factors for the occurrence of preterm birth in each group. Preterm births accounted for 21.2% (2,521 cases) of all cases, with the rates of 2.6% (317 cases), 6.7% (800 cases), and 11.8% (1,404 cases) at 22-27, 28-33, and 34-36 weeks of gestation, respectively. To prevent preterm birth in Okinawa Prefecture, the present study specifically focused on patient background characteristics. In the multinomial logistic regression, the risk factors for preterm birth at 22-27 weeks of gestation were previous preterm birth (P < 0.0001) and lower age (P = 0.026); at 28-33 weeks of gestation, the risk factors were previous preterm birth (P < 0.0001) and history of cervical conization (P = 0.009); and at 34-36 weeks of gestation, only previous preterm birth (P < 0.0001) was a risk factor. Previous preterm birth, younger age, and history of cervical conization were risk factors for Preterm birth in Okinawa. To reduce premature births in Okinawa Prefecture, it is important to pick up women with these risk factors and provide them with appropriate guidance and education on an ongoing basis.

Screening and diagnosis of chromosomal abnormalities in twin pregnancy.

Twin pregnancies are at an increased risk of adverse pregnancy and perinatal outcome as compared to singleton gestations, mainly as the consequence of the higher rate of preterm birth, chromosomal as well as structural anomalies, placental abnormalities, and complications unique to monochorionic placentation. Screening for chromosomal anomalies poses diagnostic and management challenges when applied to twin pregnancies. The recent implementation of cell-free fetal DNA (cffDNA) in clinical practice raises the questions whether a more accurate test should be offered to twin pregnancies in view of the higher false positive rate of traditional screening and the higher risk of fetal loss following amniocentesis or chorionic villus sampling (CVS) in multiple gestations. Finally, twin pregnancies require a tailored approach for aneuploidy screening, such as nuchal translucency (NT) or crown rump length discordance, discordant fetal anomalies, or monoamniotic gestations. The present review aims to provide an up-to-date critical appraisal of screening and prenatal diagnosis of chromosomal abnormalities in twin pregnancies.

County-level jail incarceration, community economic distress, rurality, and preterm birth among women in the US South.

The USA has higher rates of preterm birth and incarceration than any other developed nation, with rates of both being highest in Southern states and among Black Americans, potentially due to rurality and socioeconomic factors. To test our hypothesis that prior-year county-level rates of jail admission, economic distress, and rurality were positively associated with premature birth rates in the county of delivery in 2019 and that the strength of these associations is greater for Black women than for White or Hispanic women, we merged five datasets to perform multivariable analysis of data from 766 counties across 12 Southern/rural states. We used multivariable linear regression to model the percentage of babies born premature, stratified by Black (Model 1), Hispanic (Model 2), and White (Model 3) mothers. Each model included all three independent variables of interest measured using data from the Vera Institute, Distressed Communities Index, and Index of Relative Rurality. In fully fitted stratified models, economic distress was positively associated with premature births among Black (F = 33.81, p < 0.0001) and White (F = 26.50, p < 0.0001) mothers. Rurality was associated with premature births among White mothers (F = 20.02, p < 0.0001). Jail admission rate was not associated with premature births among any racial group, and none of the study variables were associated with premature births among Hispanic mothers. Understanding the connections between preterm birth and enduring structural inequities is a necessary scientific endeavor to advance to later translational stages in health-disparities research.

Achieving more with less: lessons from country-level analyses of caesarean delivery and perinatal outcomes in Europe

Abstract Background There is consensus that caesarean delivery (CD) is a lifesaving procedure for both mother and child in emergency situations and that CD without medical indication should be avoided. However, the rate that optimally balances the risks and benefits of CD is unresolved. In 1985, the World Health Organization concluded that the CD rate should be no more than 10-15%; subsequent reviews relating CD rates to infant mortality show no benefits at the country-level for rates higher than 15-19%. However, stillbirth has not been investigated because comparable international stillbirth data are not readily available. Methods We conducted an ecological study in 25 European countries from 2015 to 2019 utilizing data from routine birth data sources aggregated using the Euro-Peristat PHIRI federated data analysis protocol. We assessed country-level associations between CD rates and perinatal outcomes (singleton preterm birth, stillbirth at ≤ 24 weeks’ gestational age, neonatal death) for all years using Pearson correlations, adjusted for clustering of years within country. Correlations were also estimated between linear trends over time in the indicators. Results The median [range] of CD rates was 23.1% [16.2 to 56.9] in 21 participating countries, while these were 6.9% [5.3 to 11.9] for preterm birth, 3.3 per 1000 total births [1.8 to 7.6] for stillbirth and 1.9 per 1000 live births [0.7 to 6.1] for neonatal mortality. The CD rate was not associated with the stillbirth rate (cluster-adjusted rho: -.01, P=.94) or with the neonatal mortality rate (rho:.27, P=.27). However, there was a strong positive correlation with the preterm birth rate (rho:.81, P&amp;lt;.001). Results were similar in time trend analyses. Conclusions Higher CD rates were not associated with lower stillbirth or neonatal mortality rates, but were strongly correlated with higher preterm birth rates. This study suggests no benefits and indicates potential harms for higher CD rates in Europe.

Effects of gonadotropin-releasing hormone agonist pretreatment on frozen embryo transfer outcomes in artificial cycles: a meta-analysis.

Gonadotropin-releasing hormone agonist (GnRHa) before artificial cycle (AC) is expected to improve pregnancy outcomes in frozen-thawed embryo transfer (FET). Many studies have explored the impact of GnRHa pretreatment of AC in FET, but the results were inconsistent. This meta-analysis was performed to systematically evaluate the effect of GnRHa pretreatment on AC in FET. The last search was January 31, 2022. Randomized controlled trials and cohort studies aiming to assess the effect of GnRHa as the pretreatment of AC for endometrial preparation in FET were included. GnRHa was used before AC in the treatment group. In the control group, no pretreatment was used before AC. The eligible studies included at least one of the following outcomes: implantation, clinical pregnancy, and live birth. We calculated the odds ratio (OR) or mean difference (MD) and 95% confidence interval (CI) for each study and used a random-effects or fixed model to estimate the results. 27 articles (10 RCTs and 17 non-RCTs) and 14152 patients were included. AC + GnRHa improved the implantation rate (OR = 1.31, 95% CI 1.03-1.66, I2 = 79%), clinical pregnancy rate (OR = 1.27, 95% CI 1.10-1.45, I2 = 53%), and live birth rate (OR = 1.16, 95% CI 1.05-1.29, I2 = 39%). We also found that AC + GnRHa increased the implantation rate (OR = 1.35, 95% CI 1.07-1.69, I2 = 53%) and clinical pregnancy rate (OR = 1.50, 95% CI 1.12-2.01, I2 = 50%) in repeated implantation failure. In addition, AC + GnRHa was positively associated with preterm birth (OR = 1.5, 95% CI 1.15-1.94, I2 = 0%). GnRHa pretreatment in FET can improve implantation, clinical pregnancy, and live birth rates, especially in patients with repeated implantation failure. GnRHa pretreatment seems to improve FET outcomes, though with a higher preterm birth rate.

Occurrence of live-born twins with birth weight-discordance and its relationship to the adverse birth outcomes

Objective: To investigate the occurrence of live-born twins with birth weight-discordance and its relationship to adverse birth outcomes. Methods: A retrospective analysis was performed on 4 011 pairs of live-born twins in the Third Affiliated Hospital of Guangzhou Medical University from January 2011 to December 2020. Based on the birth-weight discordance (∆BW, ∆BW=(birth-weightbig-birth-weightsmall)/birth-weightbig×100%)), twins were divided into 4 groups, including ∆BW≤15%,>15%-20%,>20%-25%, and>25%. The differences in maternal and neonatal outcomes among 4 groups were explored. Then the correlation between ∆BW and neonatal adverse outcomes were explored. Results: The ΔBW was 9 (4, 16)% and males were accounted for 53.8% (4 315 cases) of 4 011 pairs of twins. The gestational age was (35.3±2.7) weeks at birth. There were 2 908 pairs (72.5%) of twins with ΔBW≤15%, 481 pairs (12.0%) with ΔBW>15%-20%, 281 pairs (7.0%) with ΔBW 20%-≤25%, and 341 twin pairs (8.5%) with ΔBW>25%. With ∆BW of 20% as the diagnostic cutoff, the incidence of birth weight discordance was 15.5% (622/4 011). The proportion of natural births in the ∆BW≤15% group was higher than that in the ∆BW>15%-20% group (10.5% (288/2 740) vs. 6.3% (29/463), P<0.008 3). The ∆BW>25% group had a significantly higher prevalence of maternal hypertensive disorders during pregnancy than that of the other 3 groups (25.5% (87/341) vs. 16.7% (47/281) vs.17.3% (83/480) vs. 13.8% (400/2 899), all P<0.008 3). Univariate analysis found that the ΔBW>25% group had a lower gestational age and a higher rate of preterm birth than the other groups. The rate of extremely low birth weight (ELBW) or very low birth weight (VLBW), small for gestational age (SGA), and transferring to the department of neonatology in the smaller twins were significantly different among the 4 groups (all P<0.05). Multivariate analysis showed that higher degree of birth weight discordance was all positively associated with the rate of ELBW, SGA, and transferring to the department of neonatology in smaller twin, even after adjusting maternal age and gestational hypertension, year of birth, mode of delivery, gender, and gestational age (all P<0.05). Moreover, the Mantel-Haenszel test also indicated that there were significantly low to moderate correlations between ΔBW and the unfavorable outcomes (r=0.22, 0.53, 0.21, all P<0.001, respectively). The receiver operating characteristic (ROC) curve found that adverse birth outcomes would be well predicted by birth weight-discordant when the diagnostic cut-off of ΔBW was 12%-17%, with an acceptable sensitivity (0.53-0.78) and a high specificity (0.72-0.79). Conclusions: Birth weight discordant is not uncommon in live-born twins, and is associated with adverse outcomes including ELBW, SGA, and transferring to the department of neonatology in the small twins. Besides, the risk is linearly related to the increase of ΔBW. In the future, more researches are needed to explore the underline mechanism and long-term impact of birth weight discordance, to guide the prevention and management.

Platelet protease activated receptor 4 (PAR 4) receptor genotype is associated with an increased risk of preterm birth

BackgroundPlatelet protease activated receptor‐4 (PAR4) Thr120 is a common genetic variant associated with increased platelet activity. Increased platelet activity is implicated in the pathogenesis of preeclampsia and preterm birth. ObjectiveCompare the rate of preeclampsia and preterm birth in pregnant individuals homozygous for PAR4 Thr120 variant vs not. Study DesignThis is a prospective cohort study of patients who delivered November 2020–July 2021. Maternal blood collected on admission for PAR4 genotyping. The primary outcome was the rate of preeclampsia/gestational hypertension in those with Thr/Thr genotype compared with Ala/Thr or Ala/Ala. Secondary outcomes included rates of preterm birth and placental pathology. ResultsThree hundred and twenty singletons were included and 52 (16.3%) were PAR4 Thr/Thr. Those PAR4 Thr/Thr were more likely to be Black (67.3% vs 29.5%, p < .001), younger (28 ± 6 vs 31 ± 6, p = .004), and have higher body mass index (35.2 ± 6.8 vs 33.1 ± 7.4, p = .047). There was no difference in preeclampsia/gestational hypertension (19.2% vs 22.8%, p = .705). Those Thr/Thr had a significantly higher rate of preterm birth (15.4% vs 3.7%, adjusted odds ratio [aOR] 4.04 [1.47–11.10], p = .007), indicated preterm birth because of fetal growth restriction or preeclampsia (5.8% vs 0.4%, aOR 10.03 [1.48–67.87], p = .02), spontaneous preterm birth (7.7% vs 2.2%, aOR 4.81 [1.27–18.27], p = .02), and placental intervillous thrombosis (18.5% vs 7.9%, aOR 4.12 [1.14–14.92], p = .03). ConclusionPlatelet receptor PAR4 Thr120 is a common variant associated with an increased risk of placental vascular pathology and preterm birth in homozygous individuals. Although a cohort study cannot establish causation, this strong association warrants further exploration.