Impact of marginal cord insertion on perinatal outcomes: a systematic review and meta-analysis

Association between placental location and cord insertion site with pre-eclampsia: a retrospective cohort study

OBJECTIVE

The relationship between placental location in pregnancies without previa and adverse pregnancy outcomes has not been well studied. Additionally, the impact of abnormal cord insertion sites remains controversial. Therefore, the objective of this study was to explore the adverse outcomes associated with placental location and abnormal cord insertion in nulliparous women and to assess their impact on pregnancy outcomes.

METHODS

This retrospective cohort study was conducted at a single tertiary hospital between January 2019 and June 2022. The study included nulliparous women with singleton pregnancies who delivered live infants and had available data on placental location and umbilical cord insertion site from a second- or third-trimester ultrasound. Placental location was categorized as anterior or posterior using transabdominal ultrasonography. The association between placental location/cord insertion site and pre-eclampsia was evaluated using multivariate logistic regression analysis. We compared the area under the curve to evaluate the impact of placental location and cord insertion site on pre-eclampsia.

RESULTS

A total of 2219 pregnancies were included in the study. Pre-eclampsia occurred significantly more frequently in the anterior group than in the posterior group (8.21% vs. 3.04%, p < .001). In multivariate analysis investigating the association between placental location and pre-eclampsia, anterior placenta and marginal cord insertion showed increased odds ratios for pre-eclampsia of 3.05 (95% confidence interval [CI] 1.68-6.58) and 3.64 (95% CI 1.90-6.97), respectively. Receiver operating characteristic (ROC) curves were constructed to predict pre-eclampsia using independent factors from multivariate analyses. Model I, including maternal age, pre-pregnancy body mass index, in vitro fertilization, chronic hypertension, overt diabetes, kidney disease, and hematologic diseases, achieved an area under the ROC curve of 0.70 (95% CI 0.65-0.75). Adding cord insertion site and placental location to the model (Model II) improved its predictive performance, resulting in an area under the ROC curve of 0.749 (95% CI 0.70-0.79, p = .02).

CONCLUSIONS

Anterior placenta and marginal cord insertion were associated with an increased risk of pre-eclampsia. Further studies on prospective cohorts are necessary to validate these findings.

Maternal-fetal comorbidities and obstetrical outcomes of fetal single ventricle cardiac defects: 10 years' experience with a multidisciplinary management protocol at a single center

OBJECTIVES

To describe and compare maternal and fetal comorbidities and obstetrical outcomes in pregnancies with hypoplastic left and right heart (HLHS and HRH) single ventricle cardiac defects (SVCD) from a single center under a multidisciplinary protocol.

METHOD

A single center retrospective review of fetal SVCD from 2013 to 2022. Maternal-fetal comorbidities, delivery, and postnatal outcomes were compared between HLHS and HRH using descriptive statistics and univariate and multivariate analyses.

RESULTS

Of 181 SVCD pregnancies (131 HLHS; 50 HRH), 9% underwent termination, 4% elected comfort care, 5 died in utero and 147/152 liveborns survived to the first cardiac intervention. Cesarean delivery occurred in 57 cases (37%), planned in 36 and unplanned in 21. Comorbidities, which did not differ between HLHS and HRH, included fetal growth restriction (FGR, 17%), prematurity (14%), maternal hypertension (9%), maternal obesity (50%), fetal extracardiac anomalies and chromosome anomalies (12%, 13%). In multivariate analysis, only earlier gestational age at delivery and oligohydramnios predicted decreased odds of survival at one year.

CONCLUSION

Maternal-fetal comorbidities are common in both HLHS and HRH. Earlier gestational age at delivery and oligohydramnios predict lower postnatal survival. FGR, even with severe early onset, did not significantly impact short- or long-term neonatal survival in single ventricle conditions.

Prenatal diagnosis of bilobate placenta: incidence, risk factors and impact on pregnancy outcomes

OBJECTIVES

To investigate the incidence and risk factors of bilobate placenta, as well as to assess its impact on preeclampsia (PE), preterm delivery (PTD) and small-for-gestational age (SGA) neonates.

METHODS

A prospective study of singleton pregnancies, undergoing routine anomaly scan at 20+0-23+6 gestational weeks, was conducted, between 2018 and 2022. The impact of prenatally diagnosed bilobate placenta on PE, PTD and SGA was assessed. Multivariate logistic regression models were employed to assess the independent association between bilobate placenta and the main pregnancy outcomes, using specific confounders. Additionally, a risk factor analysis was performed.

RESULTS

The study population included 6,454 pregnancies; the incidence of prenatally diagnosed bilobate placenta was 2.0 % (n=129). Bilobate placenta was associated with PE (aOR: 1.721; 95 % CI: 1.014-2.922), while no statistically significant association was found between this anatomical variation and SGA (aOR: 1.059; 95 % CI: 0.665-1.686) or PTD (aOR: 1.317; 95 % CI: 0.773-2.246). Furthermore, pregnancies with prenatally diagnosed bilobate placenta had an increased prevalence of abnormal cord insertion (marginal or velamentous) (9.8 vs. 27.1 %; p<0.001) and increased mean UtA PI z-score (0.03 vs. 0.23; p=0.039). Conception via ART (aOR: 3.669; 95 % CI: 2.248-5.989), previous history of 1st trimester miscarriage (aOR: 1.814; 95 % CI: 1.218-2.700) and advancing maternal age (aOR: 1.069; 95 % CI: 1.031-1.110) were identified as major risk factors for bilobate placenta.

CONCLUSIONS

Bilobate placenta, excluding cases of co-existing vasa previa, is associated with higher incidence of PE, increased mean UtA PI z-score and higher probability of abnormal cord insertion, but not with increased risk for SGA or PTD. It is more common in pregnancies following ART and in women with a previous 1st trimester miscarriage.

Associations between velamentous or marginal cord insertion and risk of adverse perinatal outcomes in twin pregnancies: a retrospective cohort study

BACKGROUND

Velamentous cord insertion (VCI) and marginal cord insertion (MCI) are well-known risk factors for adverse perinatal outcomes in singleton pregnancies. However, the potential links between VCI or MCI and perinatal outcomes in twin pregnancies have yet to be systematically evaluated. This study aimed to investigate the relationships between VCI or MCI and perinatal outcomes in twin pregnancies.

METHODS

This retrospective single-center cohort study included women with twin pregnancies who gave birth in a tertiary hospital in Southwest, China between January 2017 and December 2022. VCI and MCI were identified by abdominal ultrasound and confirmed after placental delivery. Logistic regression, multinomial logit regression and generalized estimation equation models were used to evaluate the association between VCI or MCI and perinatal outcomes.

RESULTS

A total of 3682 twin pregnancies were included, including 100 (2.7%) pregnancies with VCI and 149 (4.0%) pregnancies with MCI. Compared to pregnancies with normal cord insertion, both monochorionic and dichorionic pregnancies with VCI were associated with an increased risk of preterm delivery 32-34 weeks (aRRR 2.94, 95% CI 1.03-8.39; aRRR 2.55, 95% CI 1.19-5.46, respectively), while pregnancies with MCI were not associated with preterm delivery. VCI was associated with a higher incidence of placental previa (aOR 6.36, 95% CI 1.92-21.04) in monochorionic pregnancies and placental accreta (aOR 1.85, 95% CI 1.06-3.23) in dichorionic pregnancies. MCI was associated with an increased risk of preeclampsia (aOR 3.07, 95% CI 1.49-6.32), intertwin birthweight discordance ≥ 20% (aOR 2.40, 95% CI 1.08-5.60) and selective fetal growth restriction (aOR 2.46, 95% CI 1.08-5.60) in monochorionic pregnancies and small-for-gestational age neonates (aOR 1.97, 95% CI 1.24-3.14) in dichorionic pregnancies.

CONCLUSIONS

VCI was associated with an increased risk of preterm delivery in twin pregnancies irrespective of chorionicity, whereas MCI was associated with an increased preeclampsia risk, significant intertwin birthweight discordance in monochorionic pregnancies and small-for-gestational age neonates in dichorionic pregnancies.

Prenatal Diagnosis of Isolated Single Umbilical Artery: Incidence, Risk Factors and Impact on Pregnancy Outcomes

Objectives: To assess the incidence of prenatally diagnosed isolated single umbilical artery (iSUA) and its impact on major pregnancy outcomes, as well as to investigate potential risk factors. Materials and methods: A prospective study of singleton pregnancies, undergoing routine anomaly scans at 20⁺⁰-24⁺⁰ weeks of gestation, was carried out from 2018 to 2022. The effect of sonographically detected iSUA on small-for-gestational-age neonates (SGA) and preterm delivery (PTD) was evaluated using parameterized Student's t-test, nonparametric Mann-Whitney U test and the chi-square test. Multivariable logistic regression models were implemented to assess the independent association between iSUA and the main outcomes, as well as with potential risk factors, while adjusting for specific confounders. Results: The study population included 6528 singleton pregnancies and the incidence of prenatally diagnosed iSUA was 1.3%. Prenatally diagnosed iSUA had a statistically significant association with both SGA neonates (aOR: 1.909; 95% CI: 1.152-3.163) and PTD (aOR: 1.903; 95% CI: 1.035-3.498), while no association was identified between this sonographic finding and preeclampsia. With regard to risk factors, conception via assisted reproductive technology (ART) was associated with increased risk of iSUA (aOR: 2.234; 95% CI: 1.104-4.523), while no other independent predictor for the development of this anatomical variation was identified. Conclusions: Prenatally diagnosed iSUA seems to be associated with a higher incidence of SGA and PTD and is more common in pregnancies following ART, which constitutes a novel finding.