First trimester risk of preeclampsia and rate of spontaneous birth in patients without preeclampsia

Mapping genetic susceptibility to spontaneous preterm birth: analysis of Utah pedigrees to find inherited genetic factors

BACKGROUND

Spontaneous preterm birth (SPTB) is the leading cause of neonatal morbidity and mortality. It is a final common pathway for multiple etiologies, some of which are well known while others likely remain to be identified. Despite recent advancements in identifying genetic risk factors, the mechanisms of many SPTBs remain poorly understood due to the phenotypic heterogeneity and complexity. Large family-based studies decrease heterogeneity and improve power to identify genetic causes of SPTB.

OBJECTIVE

To identify inherited genetic factors in SPTB etiology using large families.

STUDY DESIGN

Using the Utah Population Database, which links a 4.5 million-person genealogy to state birth certificate and fetal death records, we identified large pedigrees containing multiple women with early SPTB (<34 weeks' gestation) and any SPTB (<37 weeks' gestation). We reviewed birth certificate data to exclude those with maternal and fetal diagnoses associated with iatrogenic preterm birth, resulting in 74 large multiplex pedigrees for early SPTB. Enrolled women with SPTB underwent comprehensive clinical phenotyping with review of primary medical records. Seven pedigrees, each containing at least 3 sampled women with SPTB, were the focus of this genetic study. High-density single-nucleotide polymorphism genotyping was conducted in maternal peripheral blood samples from women in the seven pedigrees. Shared genomic segments analysis was performed to identify genome-wide significant chromosomal regions shared in excess by women with SPTB.

RESULTS

We identified two genome-wide significant chromosomal regions. In single-pedigree SGS analysis, a 1.75 Mega base region in chromosome 8 (8q24.23) was shared by 5 out of 6 women with SPTB in a single large pedigree (false positive rate=0.028). In duo-pedigree analysis, a 1.05 Mega base region in the same 8q24.23 locus was identified in a second pedigree (false-positive rate [duo]=0.0019). The intersecting region at the 8q24.23 locus contains FAM135B (family with sequence similarity 135 member B) and KHDRBS3 (KH RNA-binding domain containing, signal transduction associated 3) genes, which have previously been implicated in oncogenesis and ovarian cancer, respectively. Duo-pedigree SPTB analysis also identified a second genome-wide significant 67 kilo base locus in chromosome 12 (12q21.1-q21.2) that was shared by all women with SPTB in two independent pedigrees (false-positive rate [duo]=0.01). The intersecting region at the 12q21.1-q21.2 locus contains CAPS2 (calcyphosine 2) and KCNC2 (potassium voltage-gated channel subfamily C member 2) genes, both implicated in vascular-related complications of pregnancy and preterm labor.

CONCLUSION

Using large SPTB families, we identified shared chromosomal regions (8q24.23 and 12q21.1-q21.2), providing evidence for inherited (segregating) risk loci in SPTB etiology. Further investigation into genes in SPTB etiology, including functional validation may provide avenues for novel therapeutic development and guide efforts for SPTB prevention to prolong pregnancy and improve outcomes.

Inflammatory Indices and Preterm Delivery: A New Horizon in Obstetric Risk Assessment

Objective: Preterm delivery is a leading cause of neonatal morbidity and mortality globally, with inflammation playing a crucial role in its pathophysiology. This study aimed to evaluate the predictive value of systemic inflammatory response indices in identifying pregnant women at risk of preterm delivery. Methods: This retrospective study analyzed data from 1128 pregnant women admitted to a tertiary care hospital between 2020 and 2025. Patients were classified into two groups: preterm delivery (n = 528) and term delivery (n = 600). Demographic characteristics, obstetric history, neonatal outcomes, and inflammatory indices were compared. Results: The preterm delivery group showed a significantly higher systemic inflammatory response index (SIRI) (p < 0.001), systemic immune-inflammation index (SII) (p < 0.001), neutrophil/lymphocyte ratio (NLR) (p < 0.001), and monocyte/lymphocyte ratio (MLR) (p < 0.001) than the term delivery group, while platelet/lymphocyte ratio (PLR) levels were significantly lower (p = 0.002). Inflammatory indices were higher in early preterm delivery cases (p < 0.001) than in middle and late preterm cases. Multivariate logistic regression identified the SIRI (p = 0.015) and NLR (p < 0.001) as independent predictors of preterm delivery, while the PLR showed an inverse association (p = 0.002). Higher inflammatory indices correlated with lower 1st and 5th minute APGAR scores (p < 0.001) and increased neonatal intensive care unit (NICU) admission rates (p < 0.001). NICU stay was prolonged in neonates born to mothers with elevated SIRI and NLR levels (p < 0.001). Conclusions: Integrating these inflammatory indices into obstetric risk assessment may enhance early detection and intervention strategies, potentially improving maternal and neonatal prognosis.

Cadmium Associated Preeclampsia: A Systematic Literature Review of Pregnancy and Birth Outcomes

Preeclampsia (PE), caused by multiple factors, is one of the most serious complications of pregnancy. Cadmium (Cd) is a heavy metal environmental pollutant, reproductive toxicant, and endocrine disruptor, which can increase the risk of PE. Cd toxicity due to occupational, diet, and environmental factors has worsened the risk. Studies showed elevated Cd concentration in maternal blood and placenta of PE women. However, the implicit association between Cd associated PE is still not highlighted. We systematically reviewed Cd-associated PE and its effect on pregnancy and birth outcomes. Based on "Preferred reporting items for systematic reviews and meta-analyses (PRISMA)" guidelines, eighty-six studies were identified by PubMed, Web of Science (WOS), and Scopus databases. Publications were included until October 2023 and articles screened based on our inclusion criteria. Our study identified that the exposure of controlled and uncontrolled Cd induces PE, which negatively affects pregnancy and birth outcomes. Given the serious nature of this finding, Cd is a potential adverse agent that impacts pregnancy and future neonatal health. Further comprehensive studies covering the whole trimesters of pregnancy and neonatal developments are warranted. Data on the molecular mechanisms behind Cd-induced PE is also essential for potential preventive, diagnostic, or therapeutic targets.

Soluble fms-like tyrosine kinase-1/placental growth factor ratio at 36 weeks' gestation: association with spontaneous onset of labor and intrapartum fetal compromise in low-risk pregnancies

BACKGROUND

Previous evidence showed that placental dysfunction triggers spontaneous preterm or term births and intrapartum fetal compromise and often requires urgent delivery, thereby exposing both the fetus and the mother to significant risks. Predicting spontaneous labor onset and intrapartum fetal compromise could improve obstetrical management and outcomes, but this is currently difficult, particularly in low-risk populations.

OBJECTIVE

The objective of this study was to examine whether placental dysfunction, as assessed at 36 weeks' gestation by the soluble fms-like tyrosine kinase-1 to placental growth factor ratio, is associated with the interval to spontaneous onset of labor and intrapartum fetal compromise that requires cesarean delivery in a routinely examined population.

STUDY DESIGN

This was a retrospective analysis of prospectively collected data of women with singleton pregnancies who underwent routine assessment at 35+0 to 36+6 weeks' gestation at the King's College Hospital (London, England). Using a general linear model, the study examined the outcomes related to the soluble fms-like tyrosine kinase-1/placental growth factor ratio, including the time interval from testing to spontaneous onset of labor and the subsequent rate of fetal compromise that required a cesarean delivery. Patients who underwent induction of labor or prelabor cesarean deliveries were excluded from the study. Competing risks regression and Cox regression models were used to estimate the cumulative incidence and the risk of the outcomes of interest.

RESULTS

In the screened population of 45,375 patients, 23,831 (52.5%) had spontaneous onset of labor and were included in the analysis. Cases with an soluble fms-like tyrosine kinase-1/placental growth factor ratio >50 delivered about 1 week earlier than those with a ratio of ≤50 (39.2 vs 40.0 weeks' gestation; P<.001). The general linear model showed that a larger soluble fms-like tyrosine kinase-1/placental growth factor ratio was associated with earlier spontaneous onset of labor (P<.001), particularly among multiparous women. The soluble fms-like tyrosine kinase-1/placental growth factor ratio was significantly associated, as expected, with cases of preeclampsia and advanced maternal age. The cumulative incidence of spontaneous onset of labor was significantly higher in cases with an soluble fms-like tyrosine kinase-1/placental growth factor ratio >50 than in those with a ratio 50 (P<.001). Cox regression showed that the risk for spontaneous onset of labor increased with an soluble fms-like tyrosine kinase-1/placental growth factor ratio >50 (hazard ratio, 1.424; 95% confidence interval, 1.253-1.618; P<.001) and, as expected, the risk was mitigated over time from when the soluble fms-like tyrosine kinase-1/placental growth factor ratio was measured to spontaneous labor onset (P<.001). Cases with intrapartum fetal compromise had a higher mean soluble fms-like tyrosine kinase-1/placental growth factor ratio than those without intrapartum fetal compromise (21.79 vs 17.67; P<.001). Qualitative addition of fetal compromise to the general linear model showed a higher soluble fms-like tyrosine kinase-1/placental growth factor ratio in cases with fetal compromise than in those without fetal compromise (P=.014). Competing risks regression showed a positive dose-response effect for fetal compromise with increasing soluble fms-like tyrosine kinase-1/placental growth factor ratios (P<.001). Above and below the optimal cutoff of 50, the quoted cumulative incidences were 6.7% and 4.7%, respectively (P<.001). The effect of the soluble fms-like tyrosine kinase-1/placental growth factor ratio remained significant even after adjusting for preeclampsia, which is a well-known major risk factor for fetal compromise. Finally, the proportion of cases with intrapartum fetal compromise who had an soluble fms-like tyrosine kinase-1/placental growth factor ratio >50 decreased from 35% to 0% with advancing gestation.

CONCLUSION

This study showed that an increased soluble fms-like tyrosine kinase-1/placental growth factor ratio at 36 weeks' gestation is associated with an earlier gestational age at spontaneous onset of labor and higher rates of intrapartum fetal compromise. There are 2 major implications, namely an soluble fms-like tyrosine kinase-1/placental growth factor ratio >50 indicates imminent labor onset with about a 40% mean risk increase and immediate clinical translation for term pregnancy monitoring. In addition, an increased soluble fms-like tyrosine kinase-1/placental growth factor ratio increases the risk for intrapartum fetal compromise, although outcome variability indicates reassessment within multimarker models.

Placental Proteomics Reveals an Elevated Level of Aldo-Keto Reductase 1-B1, Highlighting Its Potential Role in Spontaneous Preterm Birth

Preterm birth (PTB) refers to the delivery of a baby before the completion of 37 weeks of gestation. It is a significant global health issue with implications for both mothers and neonates. The placenta is a transient organ crucial in the sustenance of pregnancy until parturition; its dysfunction is associated with different adverse pregnancy outcomes, including PTB. We conducted a nested case-control study of 40 placental tissue samples from preterm and term deliveries to study their comparative protein profiles. Label-free quantitation (LFQ) revealed 23 differentially expressed proteins (DEPs). Aldo-keto reductase-B1 (AKR1B1) protein expression profile exhibited a declining trajectory with an increasing period of gestation (POG). Immunoblotting and immunohistochemistry analyses of placental samples also revealed elevated protein levels in extreme preterm samples. AKR1B1 is a functional Prostaglandin F synthase responsible for the synthesis of Prostaglandin-F2α, a prostanoid that is elevated during parturition and involved in cervical ripening, membrane rupture, myometrial contraction, and inflammation. Hence, our finding supports the idea that elevated AKR1B1 levels play a significant role in the pathology of preterm birth by amplifying Prostaglandin-F2α synthesis in the placental milieu and can be further explored as a potential predictor of this condition. Data are available via ProteomeXchange with the identifier PXD043480.

Causal Relationships Between Leukocyte Subsets and Adverse Fetal Outcomes: A Mendelian Randomization Study

Background: The tolerance and dynamic regulation of the maternal immune system during pregnancy are pivotal for ensuring fetal health. Immune cell subsets play a complex and crucial role in this process, closely linked to the neonatal health status. Despite recognizing the significance of dysregulation in the quantity and activity of immune cells in neonatal disease occurrence, their specific roles remain elusive, resulting in a dearth of clinically viable interventions for immune-mediated neonatal diseases. Materials and Methods: Employing two-sample Mendelian randomization (MR) methodology, this study systematically investigated 446 leukocyte features (N = 500,675), including leukocyte subsets, absolute cell (AC) counts, and morphological parameters (MP) and their correlation with seven adverse fetal outcomes (N = 1,100,458), encompassing fetal growth restriction (FGR), preterm birth (PTB), neonatal jaundice (NNJ), digestive system disorders of fetus and newborn (DSDFN), hemorrhagic and hematological disorders of fetus and newborn (HDFN), respiratory distress of newborn (RDN), and transitory disorders of metabolism specific to fetus and newborn (TDMSFN). Results: The results unveiled significant causal relationships between 301 leukocyte subsets and these seven adverse fetal outcomes, with 259, 245, 15, 44, 11, 32, and 68 pairs of notable associations for each adverse outcome, respectively. Furthermore, the study highlighted potential pathogenic mechanisms underlying the mutual influence among neonatal diseases. MR results indicated FGR as a robustly correlated risk factor for PTB and NNJ and showed a reciprocal causal relationship between NNJ and FGR. PTB exhibited a positive correlation with HDFN. Conclusions: This study provided profound insights into the intricate regulatory mechanisms of leukocyte subsets in neonatal diseases, paving the way for new avenues in the diagnosis and treatment of associated disorders.

The 36-week preeclampsia risk by the Fetal Medicine Foundation algorithm is associated with fetal compromise following induction of labor

BACKGROUND

Previous studies demonstrated that placental dysfunction leads to intrapartum fetal distress, particularly when an abnormal pattern of angiogenic markers is demonstrated at 36 weeks of gestation. The prediction of intrapartum fetal compromise is particularly important in patients undergoing induction of labor because of different indications for delivery, as this can be a useful in optimizing the method and timing of induction of labor.

OBJECTIVE

This study aimed to examine whether the risk of preeclampsia assessed using the Fetal Medicine Foundation algorithm (derived from a combination of maternal risk factors, mean arterial pressure, placental growth factor, and soluble fms-like tyrosine kinase-1) is associated with the risk of intrapartum fetal compromise requiring cesarean delivery in a population of patients with singleton pregnancies undergoing induction of labor for various indications.

STUDY DESIGN

This was a retrospective analysis on prospectively collected data from women with singleton pregnancies who underwent routine assessments at 35 0/7 to 36 6/7 weeks of gestation at King's College Hospital (London, United Kingdom). The study outcome was the rate of fetal compromise requiring cesarean delivery, examined in relation to the risk of preeclampsia assessed at 36 weeks of gestation using the Fetal Medicine Foundation risk model. Patients who underwent spontaneous labor and prelabor cesarean deliveries were excluded. In addition, 5 risk categories for preeclampsia were created on the basis of the Fetal Medicine Foundation 36-week risk model: A (≥1/2), B (<1/2- ≥1/5), C (<1/5- ≥1/20), D (<1/20-≥1/50), and E (<1/50). Based on the reason for induction of labor, we created 5 categories: premature rupture of membranes, postterm pregnancy (˃41 weeks of gestation), preeclampsia, fetal growth restriction (estimated fetal weight of ˂5th percentile), and preeclampsia and fetal growth restriction. A multinomial logistic regression was used to assess the risk of fetal compromise across the Fetal Medicine Foundation risk categories, accounting for all delivery outcomes (spontaneous or operative vaginal delivery and urgent cesarean delivery for fetal compromise, failure to progress, or other reasons) and allowing accurate and generalizable risk assessment of fetal compromise.

RESULTS

Of 45,375 pregnant women, 26,597 (58.6%) had spontaneous onset of labor, 6529 (14.0%) underwent elective prelabor cesarean delivery, which were excluded from the analysis. A total of 12,249 pregnant women were included, of which 182 had birth at ≤37 weeks of gestation and 1444 had fetal compromise (crude risk of 11.8%). The rate of vaginal delivery in the study population was 69.4%. The rates of fetal compromise in the 5 induction categories were 9.7% for premature rupture of membranes, 13.5% for postterm pregnancy, 14.8% for preeclampsia, 17.2% for fetal growth restriction, and 23.4% for preeclampsia and fetal growth restriction. Cases with intrapartum fetal compromise had a higher mean preeclampsia risk than cases without intrapartum fetal compromise (1/45 vs 1/81, respectively; P<.001). The risk of cesarean delivery for fetal compromise increased with (1) advancing gestational age (each week increase at 35-40 weeks: +1%; at 41-42 weeks: +5%), (2) nulliparity (+7%-10%) vs multiparity, (3) higher Fetal Medicine Foundation risk of preeclampsia (from the low-risk category of <1/50 to the high-risk category of ≥1/2: +18%; with greater effect for higher preeclampsia risk). In this study population, the rates of fetal compromise were lower with diagnoses of preeclampsia and rupture of membranes and higher with fetal growth restriction (alone or in combination with preeclampsia) and postterm pregnancy.

CONCLUSION

Our study highlights the clinical use of the Fetal Medicine Foundation 36-week PE risk model in determining the risk of fetal compromise requiring cesarean delivery after induction of labor. The same model can be combined with standard obstetric indications to induction of labour to establish the risk of fetal compromise requiring cesarean delivery. Therefore, the Fetal Medicine Foundation 36-week PE risk model can be used to optimize induction of labor.

Effect of serum uric acid level on reproductive outcome in women without polycystic ovary syndrome undergoing in vitro fertilization

BACKGROUND

Prior research showed that elevated serum uric acid (SUA) levels in women with polycystic ovary syndrome (PCOS) before in vitro fertilization or intracytoplasmic sperm injection (IVF/ICSI) treatment can lead to a lower rate of live birth and an increased risk for low birthweight. Nonetheless, it is not known whether elevated SUA results in similar reproductive outcome in women without PCOS. This study aimed to exploring the relationship between pre-pregnancy SUA levels and reproductive outcomes in non-PCOS women undergoing IVF/ICSI treatment.

METHODS

This single-center, retrospective study included 13,325 women without PCOS undergoing their first IVF/ICSI fresh embryo transfer cycles from January 2014 to December 2022 at a university-affiliated reproductive medicine center in China. The trends for pregnancy, obstetric and perinatal outcomes across quartiles of SUA levels were assessed. A logistic regression analysis was applied to control for baseline and cycle characteristics. Generalized addition model was used to draw spline smoothing plot.

RESULTS

There was no significant decreasing or increasing trend in the clinical pregnancy rate and live birth rate with the increase in quartiles of SUA levels. For Obstetric and perinatal outcomes following a single live birth, the percentage of hypertensive disorders in pregnancy (1.6-4.1%, Ptrend<0.001), gestational diabetes mellitus (5.9-13.9%, Ptrend<0.001), premature rupture of membranes (0.6-1.5%, Ptrend=0.016), preterm birth (6.3-9.2%, Ptrend=0.009), macrosomia (2.3-5.5%, Ptrend<0.001), large for gestational age (10.8-14.9%, Ptrend=0.002) all increased significantly from the lowest quartile to the highest. Logistic regression results showed that compared with those in quartile 1, the risk of maternal and infant complications mentioned above was still significantly higher in quartile 4 after adjusting for reproductive related factors. When further confounding factors were added, including body mass index (BMI), blood pressure, fasting blood glucose, and blood lipids related indicators, only gestational diabetes mellitus and macrosomia showed a significant increase.

CONCLUSION

In women without PCOS, SUA levels before IVF/ICSI treatment do not affect the probabilities of clinical pregnancy and live birth. An elevated SUA level is associated with an increased risk for hypertensive disorders in pregnancy, gestational diabetes mellitus, premature rupture of membranes, preterm birth, macrosomia, and large for gestational age. For gestational diabetes mellitus and macrosomia, the association is independent of BMI, blood pressure, blood glucose, and blood lipid.

Maternal Serum SCUBE-1: A Novel Ischemic Marker in Preeclampsia

BACKGROUND

SCUBE-1 (Signal peptide-CUB (complement C1r/C1s, Uegf, and Bmp1)-EGF (epidermal growth factor)-domain-containing protein 1) is a novel marker of ischemia, which is a cell surface-secreted protein in the platelets and endothelial cells. The aim of the study is to measure serum SCUBE-1 levels and investigate their association with uteroplacental blood flow in patients with preeclampsia.

METHODS

The study was conducted on patients with preeclampsia. Maternal serum SCUBE1 and IMA levels were the main outcomes. The control group consisted of gestational-age-matched pregnant women. Fetal umbilical artery (UA) pulsatility index (PI), middle cerebral artery PI, cerebroplacental ratio (CPR), and maternal uterine artery (UtA)-PI were also examined, and correlation analysis was performed to reveal the association between maternal serum SCUBE1 levels and Doppler findings.

RESULTS

The study group consisted of thirty-two preeclamptic patients, and the control group consisted of thirty-two uncomplicated singleton pregnancies. Maternal serum SCUBE1 and IMA levels were significantly higher in preeclamptic women compared to the control group (p < 0.000, p < 0.004, respectively). Mean UtA-PI values and fetal UA-PI values were significantly higher in preeclamptic pregnant women compared to the control group (p < 0.05, p < 0.05, respectively). However, the average CPR was significantly lower in pregnant women with preeclampsia (p < 0.05). While no significant correlation was found between maternal serum SCUBE1 levels and UA-PI and CPR (p > 0.05, p > 0.05, respectively), a significant correlation was found between right and left UtA-PI (p < 0.004, p < 0.006, respectively).

CONCLUSIONS

The maternal serum SCUBE1 level is increased in patients with preeclampsia, and this increase is significantly correlated with the maternal uterine artery pulsatility index.

Low PAPPA and Its Association with Adverse Pregnancy Outcomes in Twin Pregnancies: A Systematic Review of the Literature and Meta-Analysis

Background: It is well established in the literature that pregnancy-associated plasma protein-A (PAPP-A) is linked to several adverse pregnancy outcomes, including pre-eclampsia (PE), fetal growth restriction (FGR), and preterm birth (PTB) in singleton pregnancies. However, data regarding such an association in twin pregnancies are lacking. The primary goal of this systematic review and meta-analysis was to assess the potential value of low PAPP-A levels in the prediction of the subsequent development of hypertensive disorders of pregnancy (HDPs), PTB, and small for gestational age (SGA)/FGR fetuses in twin pregnancies and investigate its association with the development of gestational diabetes, intrauterine death (IUD) of at least one twin, and birth weight discordance (BWD) among the fetuses. Methods: Medline, Scopus, CENTRAL, Clinicaltrials.gov, and Google Scholar databases were systematically searched from inception until 31 July 2024. All observational studies reporting low PAPP-A levels after the performance of the first-trimester combined test as part of the screening for chromosomal abnormalities with reported adverse pregnancy outcomes were included. Results: The current systematic review encompassed a total of 11 studies (among which 6 were included in the current meta-analysis) that enrolled a total of 3741 patients. Low PAPP-A levels were not associated with HDPs (OR 1.25, 95% CI 0.78, 2.02, I-square test: 13%). Low PAPP-A levels were positively associated with both the development of preterm birth prior to 32 (OR 2.85, 95% CI 1.70, 4.77, I-square test: 0%) and 34 weeks of gestational age (OR 2.09, 95% CI 1.34, 3.28, I-square test: 0%). Furthermore, low PAPP-A levels were positively associated with SGA/FGR (OR 1.58, 95% CI 1.04, 2.41, I-square test: 0%). Prediction intervals indicated that the sample size that was used did not suffice to support these findings in future studies. Conclusions: Our study indicated that low PAPP-A levels are correlated with an increased incidence of adverse perinatal outcomes in twin pregnancies. Identifying women at elevated risk for such adversities in twin pregnancies may facilitate appropriate management and potential interventions, but additional studies are required to identify the underlying mechanism linking PAPP-A with those obstetrical complications.

Evaluation of outcomes and risk factors for recurrent preeclampsia in a subsequent pregnancy

PURPOSE

The aim was to evaluate the pregnancy outcomes and identify risk factors for recurrent preeclampsia (PE).

METHODS

Retrospective analysis of patients discharged with PE between January 1, 2010, and January 1, 2023, from two tertiary referral hospitals. They were classified into recurrent and non-recurrent groups based on the presence of PE in subsequent pregnancies.

RESULTS

Among 519 women who had a subsequent pregnancy after a history of PE, 153 developed recurrent PE while 366 did not. The recurrent cases included 81 preterm PE, of which 41 were early-onset PE (EOPE). Recurrent PE correlated significantly with prior EOPE, HELLP syndrome, placental abruption, and stillbirth, as well as with current chronic hypertension (CH) and type 2 diabetes. The recurrent group showed a 5.8-fold higher risk of preterm birth (PTB) compared to the non-recurrent group (50.7% vs. 8.7%). Notably, 58.1% of the PTBs in the non-recurrent group were spontaneous. Logistic regression identified previous EOPE (aOR: 4.22 [95% CI: 2.50-7.13]) and current CH (aOR: 1.86 [95% CI: 1.09-3.18]) as independent contributors for recurrent PE. Furthermore, recurrent preterm PE shared the same risk factors: previous EOPE (aOR: 5.27 [95% CI: 2.82-9.85]) and current CH (aOR: 2.99 [95% CI: 1.57-5.71]). The morbidity of CH in subsequent pregnancy peaked at 31.9% when women with a history of EOPE delivered within three years.

CONCLUSION

Previous EOPE and current CH were sequentially crucial risk factors for the development of PE and preterm PE during the next pregnancy. This may clarify risk stratification in prenatal management for women with a history of PE.

Preterm birth in singleton pregnancies conceived by in vitro fertilization or intracytoplasmic sperm injection: an overview of systematic reviews

BACKGROUND

The rate of preterm birth of singletons conceived through in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) is increased, being as high as 15% to 16% across Europe and the United States. However, the underlying etiology, phenotype, and mechanisms initiating preterm birth (PTB) are poorly understood.

OBJECTIVE

To quantify the PTB risk and examine supposed etiology in IVF/ICSI singleton pregnancies compared to naturally conceived.

STUDY DESIGN

Overview of reviews including all available systematic reviews with meta-analysis comparing PTB risk in IVF/ICSI and naturally conceived singletons. A comprehensive search of PubMed/MEDLINE, Embase, Scopus, and Cochrane Library databases was performed up to December 31, 2023. Information available on etiology, phenotype, initiation of PTB, and relevant moderators was retrieved and employed for subgroup analyses. Random-effects meta-analysis models were used for pooling effect measures. Estimates were presented as odds ratios (ORs) with 95% confidence intervals (CIs). The extent of overlap in the original studies was measured using the corrected covered area assessment. The quality of the included reviews was evaluated with the AMSTAR 2 tool. The Grading of Recommendations Assessment, Development and Evaluation approach was applied to rate evidence certainty. The protocol was registered on PROspective Register of Systematic Reviews (CRD42023411418).

RESULTS

Twelve meta-analyses (16,522,917 pregnancies; ˃433,330 IVF/ICSI) were included. IVF/ICSI singletons showed a significantly higher PTB risk compared to natural conception (PTB ˂37 weeks: OR: 1.72, 95% CI: 1.57-1.89; PTB<32 weeks: OR: 2.19, 95% CI: 1.82-2.64). Influential analysis reinforced the strength of this association. Subgroup analyses investigating supposed etiology revealed a comparable risk magnitude for spontaneous PTB (OR: 1.79, 95% CI: 1.56-2.04) and a greater risk for iatrogenic PTB (OR: 2.28, 95% CI: 1.72-3.02). PTB risk was consistent in the subgroup of conventional IVF (OR: 1.95, 95% CI: 1.76-2.15) and higher in the subgroup of fresh only (OR: 1.79, 95% CI: 1.55-2.07) vs frozen-thawed embryo transfers (OR: 1.39, 95% CI: 1.34-1.43). There was minimal study overlap (13%). The certainty of the evidence was graded as low to very low.

CONCLUSION

Singletons conceived through IVF/ICSI have a 2-fold increased risk of PTB compared to natural conception, despite the low certainty of the evidence. There is paucity of available data on PTB etiology, phenotype, or initiation. The greater risk increase is observed in fresh embryo transfers and involves iatrogenic PTB and PTB ˂32 weeks, likely attributable to placental etiology. Future studies should collect data on PTB etiology, phenotype, and initiation. IVF/ICSI pregnancies should undertake specialistic care with early screening for placental disorders, cervical length, and growth abnormalities, allowing appropriate timely follow-up, preventive measures, and therapeutic interventions strategies.

Hypertensive Disorders of Pregnancy: Diagnosis, Management and Timing of Birth

Hypertensive disorders of pregnancy are significant contributors to maternal and perinatal morbidity and mortality. The definition, classification, and management of these disorders have evolved over time. Notably, the disease classification enables caretakers to manage the disease as well as safeguard maternal and fetal health. The approach and management for pregnancies with gestational and chronic hypertension or pre-eclampsia with or without severe features should be adequately elucidated to mitigate adverse perinatal outcomes. This review aimed to present the most recent definition and classification of hypertensive disorders of pregnancy to address their management, determine the optimal timing of birth, and establish short- and long-term follow-up protocols following parturition.

Vaginal Progesterone for Pregnancy Prolongation After Arrested Preterm Labor: A Randomized Clinical Trial

Importance

Women with arrested preterm labor (APTL) are at very high risk for spontaneous preterm delivery (SPTD), the leading cause of neonatal mortality and morbidity. To date, no maintenance therapy has been found to be effective for pregnancy prolongation. A few clinical trials with considerable methodological limitations have demonstrated some efficacy for 400 mg vaginal micronized progesterone (VMP) in women with APTL.

Objective

To investigate the effectiveness of daily 400 mg VMP for the prolongation of pregnancy after APTL.

Design, Setting, and Participants

This randomized clinical trial was conducted between December 19, 2018, and February 27, 2023, in 3 university-affiliated medical centers in Israel. Participants included women with singleton and twin pregnancies after APTL following tocolysis at 24 weeks 0 days to 34 weeks 0 days' gestation. Women with a history of preterm delivery or asymptomatic cervical shortening in the current pregnancy were excluded.

Interventions

Participants were randomly allocated to receive VMP 200 mg twice a day or no treatment until 36 weeks 6 days' gestation.

Main Outcomes and Measures

The primary end points were mean number of days from study enrollment to delivery and the rate of SPTD prior to 37 weeks' gestation.

Results

A total of 129 participants were enrolled (65 in the VMP group and 64 in the no-treatment group). Mean (SD) age was 27.6 (5.1) years. Between the VMP and no-treatment groups, there was no difference in pregnancy prolongation (mean [SD], 40.0 [17.8] vs 37.4 [20.3] days; P = .44) and the rate of SPTD (16 [25%] vs 19 [30%]; relative risk, 0.8; 95% CI, 0.5-1.5; P = .52). In twin pregnancies, including 12 and 15 pairs in the VMP and no-treatment groups, respectively, VMP prolonged pregnancy (mean [SD], 43.7 [18.1] vs 26.1 [15.2] days; P = .02), postponed the delivery week (36.5 [1.4] vs 34.7 [2.2] weeks; P = .01), shortened the length of stay in the neonatal intensive care unit (4.9 [10.6] vs 13.2 [18.5] days; P = .03) and overall hospital stay (8.3 [9.6] vs 15.1 [17.2] days; P = .03), and was associated with a higher birth weight (2444 [528] vs 2018 [430] g; P = .01).

Conclusions and Relevance

These findings show that VMP given in a dosage of 200 mg twice a day following APTL is not an effective treatment to prolong pregnancy or prevent SPTD. However, VMP demonstrated beneficial effects in twin pregnancies, warranting further investigation.

Trial Registration

ClinicalTrials.gov Identifier: NCT02430233.

First-trimester serum biomarkers in twin pregnancies and adverse obstetric outcomes-a single center cohort study

PURPOSE

This study aimed to determine the association of first-trimester maternal serum biomarkers with preterm birth (PTB), fetal growth restriction (FGR) and hypertensive disorders of pregnancy (HDP) in twin pregnancies.

METHODS

This is a retrospective cohort study of twin pregnancies followed at Maternidade Dr. Alfredo da Costa, Lisbon, Portugal, between January 2010 and December 2022. We included women who completed first-trimester screening in our unit and had ongoing pregnancies with two live fetuses, and delivered after 24 weeks. Maternal characteristics, pregnancy-associated plasma protein-A (PAPP-A) and β-human chorionic gonadotropin (β-hCG) levels were analyzed for different outcomes: small for gestational age (SGA), gestational hypertension (GH), early and late-onset pre-eclampsia (PE), as well as the composite outcome of PTB associated with FGR and/or HDP. Univariable, multivariable logistic regression analyses and receiver-operating characteristic curve were used.

RESULTS

466 twin pregnancies met the inclusion criteria. Overall, 185 (39.7%) pregnancies were affected by SGA < 5th percentile and/or HDP. PAPP-A demonstrated a linear association with gestational age at birth and mean birth weight. PAPP-A proved to be an independent risk factor for SGA and PTB (< 34 and < 36 weeks) related to FGR and/or HDP. None of the women with PAPP-A MoM > 90th percentile developed early-onset PE or PTB < 34 weeks.

CONCLUSION

A high serum PAPP-A (> 90th percentile) ruled out early-onset PE and PTB < 34 weeks. Unless other major risk factors for hypertensive disorders are present, these women should not be considered candidates for aspirin prophylaxis. Nevertheless, close monitoring of all TwP for adverse obstetric outcomes is still recommended.

Etiologically Based Functional Taxonomy of the Preterm Birth Syndrome

Preterm birth (PTB) is a complex syndrome traditionally defined by a single parameter, namely, gestational age at birth (ie, ˂37 weeks). This approach has limitations for clinical usefulness and may explain the lack of progress in identifying cause-specific effective interventions. The authors offer a framework for a functional taxonomy of PTB based on (1) conceptual principles established a priori; (2) known etiologic factors; (3) specific, prospectively identified obstetric and neonatal clinical phenotypes; and (4) postnatal follow-up of growth and development up to 2 years of age. This taxonomy includes maternal, placental, and fetal conditions routinely recorded in data collection systems.

MicroRNA Associations with Preterm Labor-A Systematic Review

This systematic review delves into the connections between microRNAs and preterm labor, with a focus on identifying diagnostic and prognostic markers for this crucial pregnancy complication. Covering studies disseminated from 2018 to 2023, the review integrates discoveries from diverse pregnancy-related scenarios, encompassing gestational diabetes, hypertensive disorders and pregnancy loss. Through meticulous search strategies and rigorous quality assessments, 47 relevant studies were incorporated. The synthesis highlights the transformative potential of microRNAs as valuable diagnostic tools, offering promising avenues for early intervention. Notably, specific miRNAs demonstrate robust predictive capabilities. In conclusion, this comprehensive analysis lays the foundation for subsequent research, intervention strategies and improved outcomes in the realm of preterm labor.