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Journal of Ovarian Research Jan 2024Polycystic ovarian syndrome (PCOS) is recognized as the most prevalent endocrine disorder among women of reproductive age. While the utilization of assisted reproductive... (Meta-Analysis)
Meta-Analysis Review
Association between maternal polycystic ovarian syndrome undergoing assisted reproductive technology and pregnancy complications and neonatal outcomes: a systematic review and meta-analysis.
BACKGROUND
Polycystic ovarian syndrome (PCOS) is recognized as the most prevalent endocrine disorder among women of reproductive age. While the utilization of assisted reproductive technology (ART) has resulted in favorable outcomes for infertility treatment in PCOS patients, the inherent pathophysiological features of the condition give rise to complications and consequences during pregnancy and delivery for both the mother and offspring. This study was to assess the correlation between maternal PCOS and various pregnancy complications and neonatal outcomes undergone ART.
METHODS
A systematic search was conducted on PubMed, EmBase, and the Cochrane Library to identify observational studies that investigated the association between PCOS and the risk of various pregnancy complications and neonatal outcomes, including gestational diabetes mellitus (GDM), hypertension in pregnancy (PIH), preeclampsia (PE), preterm birth, abortion, congenital malformations (CA), small for gestational age (SGA), large for gestational age (LGA), low birth weight (LBW), macrosomia, neonatal intensive care unit (NICU) admission and birth weight. Eligible studies were selected based on predetermined inclusion and exclusion criteria. The meta-analysis was conducted using Review Manager and Stata software, with odds ratios (ORs) or mean difference (MD), confidence intervals (CIs), and heterogeneity (I) being calculated. The search was conducted up to March 2023.
RESULTS
A total of 33 studies with a combined sample size of 92,810 participants were identified. The findings indicate that PCOS is significantly associated with an increased risk of GDM (OR 1.51, 95% CI:1.17-1.94), PIH (OR 1.72, 95% CI:1.25-2.39), PE (OR 2.12, 95% CI:1.49-3.02), preterm birth (OR 1.29, 95% CI:1.21-1.39), and LBW (OR 1.29, 95% CI:1.14-1.47). In subgroup analyses, the risks of GDM (OR 1.80, 95% CI:1.23-2.62) and abortion (OR 1.41, 95% CI:1.08-1.84) were elevated in fresh embryo transferred (ET) subgroup, whereas elevated risk of PE (OR 1.82, 95% CI:1.17-2.83) and preterm birth (OR 1.31, 95% CI:1.21-1.42) was identified in frozen ET subgroup. Whatever with or without hyperandrogenism, patients with PCOS had a higher risk in preterm birth (OR 1.69, 95% CI: 1.31-2.18; OR 1.24, 95% CI:1.02-1.50) and abortion (OR 1.38, 95% CI:1.12-1.71; OR 1.23, 95% CI:1.06-1.43).
CONCLUSION
Our findings suggest that individuals with PCOS undergone ART are at a notably elevated risk for experiencing pregnancy complications and unfavorable neonatal outcomes. Nevertheless, to establish a definitive association between PCOS and pregnancy-related outcomes, it is necessary to conduct extensive prospective, blinded cohort studies and effectively control for confounding variables.
Topics: Female; Humans; Infant, Newborn; Pregnancy; Embryo Transfer; Polycystic Ovary Syndrome; Premature Birth; Prospective Studies; Reproductive Techniques, Assisted; Pregnancy Complications
PubMed: 38184624
DOI: 10.1186/s13048-023-01331-x -
PloS One 2023Maternal exposures to environmental hazards during pregnancy are key determinants of birth outcomes that affect health, cognitive and economic status later in life. In... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Maternal exposures to environmental hazards during pregnancy are key determinants of birth outcomes that affect health, cognitive and economic status later in life. In Ethiopia, various epidemiological evidences have suggested associations between environmental exposures such as household air pollution, cigarette smoking, and pesticide exposure and pregnancy outcomes such as low birth weight, preterm birth, and birth defects.
OBJECTIVE
This review aimed at generating summarized evidence on the association between maternal exposure to environmental factors (household air pollution, cigarette smoking, and pesticide) and pregnancy outcomes (birth weight, preterm birth, and birth defects) in Ethiopia.
METHOD
A systematic literature search was performed using PubMed, Google Scholar, and the Cochrane Library databases. All observational study designs were eligible for inclusion in the review. Quality assessment was conducted using the Newcastle-Ottawa Scale (NOS) quality assessment tools adopted for case-control and cross-sectional studies. The random-effects model was applied in computing the pooled estimates and their corresponding 95% confidence interval (CI). Funnel and Doi plots were used for detecting the potential publication bias. All statistical analyses were performed using comprehensive meta-analysis (CMA 2.0) and MetaXL version 5.3 software.
RESULT
The pooled estimates revealed that prenatal biomass fuel use increased the risk of giving a low birth weight baby by twofold (OR = 2.10, 95% CI: 1.33-3.31), and has no separate kitchen increases the risk of having low birth weight baby nearly by two and half times (OR = 2.48, 95% CI: 1.25-4.92). Overall, using biomass fuel as the main energy source for cooking and /or having no separate kitchen from the main house is 2.37 times more likely to give low birth weight babies (OR = 2.37, 95% CI: 1.58-3.53). Active cigarette smoker women were 4 times (OR = 4.11, 95% CI: 2.82-5.89) more prone to have low birth weight babies than nonsmokers; and passive smoker women were 2.6 times (OR = 2.63, 95% CI: 1.09-6.35) more risked to give low birth weight babies. It was also estimated that active cigarette smoker women were nearly 4 times (OR = 3.90, 95% CI: 2.36-6.45) more likely to give preterm birth babies. Pesticide exposure during pregnancy also increases the risk of the birth defect 4 times (OR = 4.44, 95% CI: 2.61-7.57) compared with non-exposed pregnant women.
CONCLUSION
Household air pollution from biomass fuel use, active and passive cigarette smoking, and pesticide exposures are significantly associated environmental risk factors for low birth weight, preterm birth, and birth defects in Ethiopia. Therefore, Pregnant and lactating women should be aware of these environmental hazards during pregnancy. Promoting clean energy and improved and efficient stoves at the household level will help to reduce household air pollution-related adverse health effects.
TRIAL REGISTRATION
PROSPERO 2022: CRD42022337140.
Topics: Infant, Newborn; Pregnancy; Infant; Female; Humans; Pregnancy Outcome; Premature Birth; Cross-Sectional Studies; Ethiopia; Lactation; Environmental Exposure; Observational Studies as Topic
PubMed: 37437038
DOI: 10.1371/journal.pone.0288240 -
American Journal of Obstetrics and... Oct 2023Among guidelines on gestational diabetes mellitus, there is an incongruity about the threshold of maternal hyperglycemia to diagnose gestational diabetes mellitus.
BACKGROUND
Among guidelines on gestational diabetes mellitus, there is an incongruity about the threshold of maternal hyperglycemia to diagnose gestational diabetes mellitus.
OBJECTIVE
This study aimed to ascertain the association between continuous glucose monitoring metrics and adverse outcomes among individuals undergoing gestational diabetes mellitus screening.
STUDY DESIGN
This was a prospective study (from June 2020 to January 2022) of individuals who underwent 2-step gestational diabetes mellitus screening at ≤30 weeks of gestation. The participants wore a blinded continuous glucose monitoring device (Dexcom G6 Pro; Dexcom, Inc, San Diego, CA) for 10 days starting when they took the 50-g glucose challenge test. The primary outcome was a composite of adverse neonatal outcomes (large for gestational age, shoulder dystocia or neonatal injury, respiratory distress, need for intravenous glucose treatment for hypoglycemia, or fetal or neonatal death). The secondary neonatal outcomes included preterm birth, neonatal intensive care unit admission, hypoglycemia, mechanical ventilation or continuous positive airway pressure, hyperbilirubinemia, and hospital length of stay. The secondary maternal outcomes included weight gain during pregnancy, hypertensive disorders of pregnancy, induction of labor, cesarean delivery, and postpartum complications. Time within the target range (63-140 mg/dL), time above the target range (>140 mg/dL) expressed as a percentage of all continuous glucose monitoring readings, and mean glucose level were analyzed. The Youden index was used to choose the threshold of ≥10% for the time above the target range and association with adverse outcomes.
RESULTS
Of 136 participants recruited, data were available from 92 individuals (67.6%). The 2-step method diagnosed gestational diabetes mellitus in 2 individuals (2.2%). Continuous glucose monitoring indicated that 17 individuals (18.5%) had time above the target range of ≥10%. Individuals with time above the target range of ≥10% had a significantly higher likelihood of composite adverse neonatal outcomes than individuals with time above the target range of <10% (63% vs 18%; P=.001). Furthermore, compared with neonates born to individuals with time above the target range of <10%, neonates born to individuals with time above the target range of ≥10% had an increased likelihood for hypoglycemia (14.5% vs 47%; P=.009) and had a longer length of stay (2 vs 4 days; P=.03). No difference in maternal outcomes was noted between the groups.
CONCLUSION
In this prospective study of individuals undergoing gestational diabetes mellitus screening, a cutoff of the time above the target range of ≥10% using continuous glucose monitoring was associated with a higher rate of neonatal adverse outcomes. A randomized trial of continuous glucose monitoring vs 2-step screening for gestational diabetes mellitus to lower the rate of adverse outcomes is underway (identification number: NCT05430204).
Topics: Female; Humans; Pregnancy; Blood Glucose; Blood Glucose Self-Monitoring; Diabetes, Gestational; Hypoglycemia; Pregnancy Outcome; Premature Birth; Prospective Studies
PubMed: 37088275
DOI: 10.1016/j.ajog.2023.04.021 -
BMC Cardiovascular Disorders Jul 2023Preterm birth has been linked with an increased risk of cardiovascular (CV) disease from childhood into adolescence and early adulthood. In this study, we aimed to...
BACKGROUND AND AIMS
Preterm birth has been linked with an increased risk of cardiovascular (CV) disease from childhood into adolescence and early adulthood. In this study, we aimed to investigate differences in CV health profiles between former term- and preterm-born infants in a cohort of Tyrolean adolescents.
METHODS
The Early Vascular Aging (EVA)-Tyrol study is a population-based non-randomized controlled trial, which prospectively enrolled 14- to 19-year-old adolescents in North Tyrol, Austria and South Tyrol, Italy between 2015 and 2018. Metrics of CV health (body mass index (BMI), systolic (SBP) and diastolic blood pressure (DBP), smoking, physical activity, dietary patterns, total cholesterol and fasting blood glucose) were assessed and compared between former term- and preterm-born girls and boys.
RESULTS
In total, 1,491 study participants (59.5% female, mean age 16.5 years) were included in the present analysis. SBP and DBP were significantly higher in former preterm-born adolescents (mean gestational age 34.6 ± 2.4 weeks) compared to term-born controls (p < 0.01). In the multivariate regression analysis these findings remained significant after adjustment for potential confounders in all models. No differences were found in all other CV health metrics. The number of participants meeting criteria for all seven health metrics to be in an ideal range was generally very low with 1.5% in former term born vs. 0.9% in former preterm born adolescents (p = 0.583).
CONCLUSIONS
Preterm birth is associated with elevated SBP and DBP in adolescence, which was even confirmed for former late preterm-born adolescents in our cohort. Our findings underscore the importance of promoting healthy lifestyles in former term- as well as preterm-born adolescents. In addition, we advise early screening for hypertension and long-term follow-up in the group of preterm-born individuals.
Topics: Infant, Newborn; Male; Infant; Adolescent; Female; Humans; Adult; Child; Young Adult; Premature Birth; Cardiovascular System; Cardiovascular Diseases; Hypertension; Austria
PubMed: 37488472
DOI: 10.1186/s12872-023-03360-2 -
European Journal of Obstetrics,... Sep 2023To evaluate maternal and perinatal outcomes of removal versus retention of cervical cerclage after premature preterm rupture of membranes (pPROM). (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To evaluate maternal and perinatal outcomes of removal versus retention of cervical cerclage after premature preterm rupture of membranes (pPROM).
STUDY DESIGN
Medline, Embase and Cochrane databases were searched electronically on February 2023 utilizing combinations of the relevant medical subject heading (MeSH) terms, keywords, and word variants that were considered suitable for the topic. Either prospective or retrospective trials were considered suitable for the inclusion. The coprimary outcome of this study were pregnancy latency >7 days from pPROM and pregnancy latency >48 h from pPROM. Random effect head to-head meta-analyses were performed to directly compare each outcome, expressing the results as summary odds ratio (OR) for dichotomous outcomes and as mean difference (MD) for continuous outcomes, plus relative 95% confidence interval (CI). Quality assessment of the included studies was performed using the Newcastle-Ottawa Scale.
RESULTS
Six studies involving a total of 377 women (169 in the "removal" and 208 in the "retention" group) were included. The rate of pregnancy prolongation >48 h was significantly lower in the removal compared to retention group (OR 0.15, 95% CI 0.07-0.31; p < 0.0001), as well as the rate of pregnancy prolongation >7 days (OR 0.30 95% CI 0.11-0.83; p = 0.02) and pregnancy latency expressed in days (MD -2.84 days, 95% CI -5.40 to -0.29; p = 0.03). The rate of chorioamnionitis was significantly lower in the removal compared to the retention group (OR 0.57 95% CI 0.34-0.96p = 0.03) as was the rate of Apgar score < 7 at 5 min (OR 0.22 95% CI 0.08-0.56; p = 0.002). There was no difference between removal and retention groups for all the other maternal and perinatal outcomes.
CONCLUSIONS
The decision whether to remove or retain cerclage in case of pPROM should balance the prematurity-related risks with that of infectious complications, thus highlighting the need for tailored management based on gestational age at occurrence of pPROM.
Topics: Pregnancy; Infant, Newborn; Female; Humans; Cerclage, Cervical; Retrospective Studies; Prospective Studies; Fetal Membranes, Premature Rupture; Pregnancy Outcome; Premature Birth
PubMed: 37481990
DOI: 10.1016/j.ejogrb.2023.07.006 -
The Journal of Maternal-fetal &... Dec 2023The objective of this study is to create a new screening for spontaneous preterm birth (sPTB) based on artificial intelligence (AI).
OBJECTIVE
The objective of this study is to create a new screening for spontaneous preterm birth (sPTB) based on artificial intelligence (AI).
METHODS
This study included 524 singleton pregnancies from 18th to 24th-week gestation after transvaginal ultrasound cervical length (CL) analyzes for screening sPTB < 35 weeks. AI model was created based on the stacking-based ensemble learning method (SBELM) by the neural network, gathering CL < 25 mm, multivariate unadjusted logistic regression (LR), and the best AI algorithm. Receiver Operating Characteristics (ROC) curve to predict sPTB < 35 weeks and area under the curve (AUC), sensitivity, specificity, accuracy, predictive positive and negative values were performed to evaluate CL < 25 mm, LR, the best algorithms of AI and SBELM.
RESULTS
The most relevant variables presented by LR were cervical funneling, index straight CL/internal angle inside the cervix (≤ 0.200), previous PTB < 37 weeks, previous curettage, no antibiotic treatment during pregnancy, and weight (≤ 58 kg), no smoking, and CL < 30.9 mm. Fixing 10% of false positive rate, CL < 25 mm and SBELM present, respectively: AUC of 0.318 and 0.808; sensitivity of 33.3% and 47,3%; specificity of 91.8 and 92.8%; positive predictive value of 23.1 and 32.7%; negative predictive value of 94.9 and 96.0%. This machine learning presented high statistical significance when compared to CL < 25 mm after T-test ( < .00001).
CONCLUSION
AI applied to clinical and ultrasonographic variables could be a viable option for screening of sPTB < 35 weeks, improving the performance of short cervix, with a low false-positive rate.
Topics: Pregnancy; Female; Infant, Newborn; Humans; Premature Birth; Artificial Intelligence; Cervical Length Measurement; Predictive Value of Tests; ROC Curve; Cervix Uteri
PubMed: 37518185
DOI: 10.1080/14767058.2023.2241100 -
PloS One 2023Visfatin, a colony-enhancing factor (pre-B-cell), is an inflammatory biomarker that is secreted from a different number of cells and appears to have some proinflammatory...
Visfatin, a colony-enhancing factor (pre-B-cell), is an inflammatory biomarker that is secreted from a different number of cells and appears to have some proinflammatory or immune-regulating effects. The aim of this study was to compare maternal saliva visfatin levels in women with preterm and term delivery. In This case-control study, women in labor before 37 weeks of gestation were the case group (n = 40) and women in labor after 37 weeks of gestation were in control group (n = 40). The saliva of the participants was sampled and maternal saliva visfatin level was measured by ELISA test. In this study, 80 pregnant women were studied in case and control groups. The mean age of case and control group was 29.1±6.9 and 30.55±5.3 years, respectively. The results revealed that the mean maternal saliva visfatin level in the preterm group (4.75±2.2) is significantly (p = 0.001) lower than that in term birth group (6.7±3.1). The results of adjusted logistic regression revealed that after adjusting for GDM, preeclampsia, pre pregnancy BMI and weight gain, the mean of maternal saliva visfatin level in the preterm group is significantly lower than that in the term group (p = 0.026). Considering that during the term pregnancy visfatin levels increase and visfatin may play a role in initiating labor, in our study due to the high visfatin level in case group although the level of maternal saliva visfatin was lower than the control group but high levels of visfatin in the case group can represent the role of visfatin in initiating labor and due to this issue can be use the role of this adipokine for early diagnosis of preterm delivery can be used to prevent, treat and improve the prognosis of this disease. Also, this study is the first study to compare the maternal saliva visfatin level between SGA and AGA group and there is no difference between these groups.
Topics: Infant, Newborn; Pregnancy; Female; Humans; Young Adult; Adult; Case-Control Studies; Nicotinamide Phosphoribosyltransferase; Saliva; Labor, Obstetric; Obstetric Labor, Premature
PubMed: 37459321
DOI: 10.1371/journal.pone.0288786 -
American Journal of Obstetrics &... Aug 2023Hypertensive disorders of pregnancy are the leading cause of indicated preterm birth; however, the optimal delivery approach for pregnancies complicated by preterm... (Observational Study)
Observational Study
BACKGROUND
Hypertensive disorders of pregnancy are the leading cause of indicated preterm birth; however, the optimal delivery approach for pregnancies complicated by preterm hypertensive disorders of pregnancy remains uncertain.
OBJECTIVE
This study aimed to compare maternal and neonatal morbidity in patients with hypertensive disorders of pregnancy who either went induction of labor or prelabor cesarean delivery at <33 weeks' gestation. In addition, we aimed to quantify the length of induction of labor and rate of vaginal delivery in those who underwent induction of labor.
STUDY DESIGN
This is a secondary analysis of an observational study which included 115,502 patients in 25 hospitals in the United States from 2008 to 2011. Patients were included in the secondary analysis if they were delivered for pregnancy associated hypertension (gestational hypertension or preeclampsia) between 23 and <33 weeks' gestation; and were excluded for known fetal anomalies, multiple gestation, fetal malpresentation or demise, or a contraindication to labor. Maternal and neonatal adverse composite outcomes were evaluated by intended mode of delivery. Secondary outcomes were duration of labor induction and rate of cesarean delivery in those who underwent labor induction.
RESULTS
A total of 471 patients met inclusion criteria, of whom 271 (58%) underwent induction of labor and 200 (42%) underwent prelabor cesarean delivery. Composite maternal morbidity was 10.2% in the induction group and 21.1% in the cesarean delivery group (unadjusted odds ratio, 0.42 [0.25-0.72]; adjusted odds ratio, 0.44 [0.26-0.76]). Neonatal morbidity in the induction group vs the cesarean delivery was 51.9% and 63.8 %, respectively (unadjusted odds ratio, 0.61 [0.42-0.89]; adjusted odds ratio, 0.71 [0.48-1.06]). The frequency of vaginal delivery in the induction group was 53% (95% confidence interval, 46.8-58.7) and the median duration of labor was 13.9 hours (interquartile range, 8.7-22.2). The frequency of vaginal birth was higher in patients at or beyond 29 weeks (39.9% at 24-28 weeks, 56.3% at 29-<33 weeks; P=.01).
CONCLUSION
Among patients delivered for hypertensive disorders of pregnancy <33 weeks, labor induction compared with prelabor cesarean delivery is associated with significantly lower odds of maternal but not neonatal morbidity. More than half of patients induced delivered vaginally, with a median duration of labor induction of 13.9 hours.
Topics: Pregnancy; Female; Infant, Newborn; Humans; United States; Hypertension, Pregnancy-Induced; Retrospective Studies; Premature Birth; Cesarean Section; Labor Presentation
PubMed: 37244639
DOI: 10.1016/j.ajogmf.2023.101032 -
Scientific Reports Feb 2024The labor is a physiological event considered to have its own circadian (diurnal) rhythm, but some of the data remain conflicting, especially for preterm births. In this...
The labor is a physiological event considered to have its own circadian (diurnal) rhythm, but some of the data remain conflicting, especially for preterm births. In this retrospective study, we analyzed the circadian trends of labor onset times in the Slovenian birth cohort from 1990 to 2018 with over 550,000 cases of singleton births. The number of term and preterm labor onsets was calculated for each hour in a day and circadian trends were evaluated for each of the study groups by modeling with a generalized Poisson distribution linked with the cosinor regression model using logarithmic link function. The induced labors were taken as the control group since the timing of labor depends mostly on the working schedule of personnel and not on the intrinsic rhythmic characteristics. For induced labors, the main peak in the number of labor cases was observed in the late morning hours (around 10 AM) for all gestational ages. The prominence of this peak becomes smaller in spontaneous premature labors with gradually disrupting rhythmicity in very preterm and extremely preterm cases. Labors starting with spontaneous contractions peak between 6 and 7 AM and lose the rhythmicity at 35 weeks of gestation while labors starting with a spontaneous rupture of membranes peak at 1 AM and lose the rhythmicity at 31 weeks of gestation, suggesting differences in underlying mechanisms. According to our knowledge, this is the first study that shows differences of circadian trends between different types of spontaneous labors, i.e., labors initiated with contraction and labors initiated with a spontaneous rupture of membranes. Moreover, the obtained results represent evidence of gradual disruption of rhythmicity from mild to extreme prematurity.
Topics: Pregnancy; Infant, Newborn; Female; Humans; Retrospective Studies; Rupture, Spontaneous; Obstetric Labor, Premature; Infant, Premature; Labor, Obstetric; Gestational Age; Premature Birth
PubMed: 38369585
DOI: 10.1038/s41598-024-54490-2 -
American Journal of Obstetrics and... Mar 2024This study aimed to quantify the association between mode of operative delivery in the second stage of labor (cesarean delivery vs operative vaginal delivery) and... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
This study aimed to quantify the association between mode of operative delivery in the second stage of labor (cesarean delivery vs operative vaginal delivery) and spontaneous preterm birth in a subsequent pregnancy.
DATA SOURCES
MEDLINE, Embase, EmCare, CINAHL, the Cochrane Library, Web of Science: Core Collection, and Scopus were searched from database inception to April 1, 2023.
STUDY ELIGIBILITY CRITERIA
All retrospective cohort studies with participants who had a second-stage cesarean delivery (defined as intrapartum cesarean delivery at full cervical dilation) or operative vaginal delivery (including forceps- and/or vacuum-assisted delivery) and that reported the rate of preterm birth (either spontaneous or not specified) in subsequent pregnancy were included.
METHODS
Both a descriptive analysis and a meta-analysis were performed. A meta-analysis was performed for dichotomous data using the Mantel-Haenszel random-effects model and used the odds ratio as an effect measure with 95% confidence intervals. The risk of bias was assessed using Cochrane's 2022 Risk Of Bias In Non-randomized Studies of Exposure tool.
RESULTS
After screening 2671 articles from 7 databases, a total of 18 retrospective cohort studies encompassing 605,138 patients were included. The pooled rates of spontaneous preterm birth in a subsequent pregnancy were 6.9% (12 studies) after second-stage cesarean delivery and 2.6% (8 studies) after operative vaginal delivery. A total of 7 studies encompassing 75,460 patients compared the primary outcome of spontaneous preterm birth after second-stage cesarean delivery vs operative vaginal delivery in an index pregnancy with an odds ratio of 2.01 (95% confidence interval, 1.57-2.58) in favor of operative vaginal delivery. However, most studies did not include important confounding factors, did not address exposure misclassification because of failed operative vaginal delivery, and considered operative vaginal delivery as a homogeneous category with no distinction between forceps- and vacuum-assisted deliveries.
CONCLUSION
Although a synthesis of the existing literature suggests that the risk of spontaneous preterm birth is higher in those with a previous second-stage cesarean delivery than in those with operative vaginal delivery, the risk of bias in these studies is very high. Findings should be interpreted with caution.
Topics: Pregnancy; Female; Infant, Newborn; Humans; Premature Birth; Retrospective Studies; Labor Stage, Second; Cohort Studies; Delivery, Obstetric
PubMed: 37673234
DOI: 10.1016/j.ajog.2023.08.033