Interpregnancy Body Mass Index Change and Risk of Intrapartum Cesarean Delivery

Determinants of failure to progress within 2 weeks of delivery: results of a multivariable analysis approach

Objective

The incidence of cesarean section (CS) for failure to progress (FP) has progressively increased; thus, knowing the factors that increase this incidence has become of crucial importance. This study aimed to find the true determinants of CS for FP within 2 weeks of delivery, proposing strategies to reduce its incidence.

Material and Methods

A group of 957 term and late preterm (≥34 weeks) singleton pregnancies with a complete gestational follow-up and an ultrasound examination within 2 weeks of delivery were included in a retrospective observational study. Epidemiological, sonographic, and perinatal data were recorded, and multivariable logistic regression analyses were applied to create models to predict the importance of different variables in the explanation of FP.

Results

Induction of labor was by far the most important modifiable factor, followed by smoking and maternal weight, while parity was the most important nonmodifiable factor, followed by maternal age and estimated fetal weight. The difference in days from the actual due date exerted no influence.

Conclusions

To reduce the incidence of CS for FP, inductions of labor should be performed only under evidence-based medicine indications and kept to a minimum. In addition, maternal overweight reduction and maternal smoking cessation should be promoted before the initiation of gestation.

Neonatal and Maternal Outcomes in Nulliparous Individuals according to Prepregnancy Body Mass Index

OBJECTIVE

 This study aimed to examine the effect of incremental changes in body mass index (BMI, kg/m2) on the association with adverse pregnancy outcomes.

STUDY DESIGN

 This was a retrospective cohort study of U.S. vital statistics Live Birth and Infant Death linked data from 2011 to 2020. We limited analyses to nulliparas with singleton pregnancies who delivered at 20 weeks or greater. Outcomes were compared according to the prepregnancy BMI category using 5 kg/m2 increments, with each of the other BMI categories sequentially as the referent. The composite neonatal outcome was defined as any neonatal death, neonatal intensive care unit (ICU), surfactant use, ventilation use, or seizure. Severe maternal morbidity was defined as any maternal ICU, transfusion, uterine rupture, and hysterectomy. Adjusted relative risks were calculated for each BMI category as a referent group, using modified Poisson regression and adjusting for confounders.

RESULTS

 A total of 11,174,890 nulliparous individuals were included. From 2011 to 2020, the proportions of individuals with BMI 40 or greater, BMI 50 or greater, and BMI 60 or greater increased significantly (from 3.1 to 4.9%, from 0.4 to 0.6%, from 0.03 to 0.06%, respectively; all trend p-values < 0.001). As BMI deviated from normal BMI, risks of neonatal and maternal adverse outcomes increased progressively. For example, as BMI deviated from normal BMI (18.5-24.9), the risk of composite neonatal outcome increased by 2% in individuals with BMI < 18.5 and up to 2.11-fold in individuals with BMI 65-69.9. When compared with BMI 40 to 44.9, BMI 35 to 39.9 was associated with an 8% decreased risk of composite neonatal outcome, whereas BMI 45 to 49.9 was associated with an 8% increased risk of composite neonatal outcome.

CONCLUSION

 Incremental increases in prepregnancy BMI are linked to higher risks of adverse pregnancy outcomes, highlighting the need for effective weight management before conception.

KEY POINTS

· Incremental BMI increases raise pregnancy risks.. · Higher BMI linked to adverse neonatal outcomes.. · Elevated BMI heightens severe maternal morbidity..

The Rate of Intrapartum Cesarean Delivery Based on Estimated Fetal Weight in Comparison to Previous Child's Birth Weight

OBJECTIVE

The aim of the study is to examine whether an estimated fetal weight of the current pregnancy greater than previous birth weight is associated with increased odds of intrapartum cesarean delivery.

STUDY DESIGN

We conducted a retrospective cohort study of all women who had more than one singleton pregnancy at 23 weeks' gestation or greater at a single labor and delivery unit. We only analyzed the second pregnancy in the dataset. We excluded women who had preterm birth in the second pregnancy. Women were categorized according to the difference between estimated fetal weight and previous birth weight-estimated fetal weight close to previous birth weight within 500 g (similar weight group); estimated fetal weight significantly (more than 500 g) greater than previous birth weight (larger weight group); and estimated fetal weight significantly (more than 500 g) lower than previous birth weight (smaller weight group). The primary outcome was intrapartum cesarean delivery. Multivariable logistic regression was performed to calculate adjusted odds ratios (aORs) with 95% confidence interval (95% confidence interval [CI]) after adjusting for predefined covariates.

RESULTS

Of 1,887 women, there were 1,415 (75%) in the similar weight group, 384 (20%) in the greater weight group, and 88 (5%) in the smaller weight group. Individuals in the larger weight group compared with those in the similar weight group had higher odds of undergoing intrapartum cesarean delivery (11.2 vs. 4.5%; aOR 2.91; 95% CI 1.91-4.45). The odds of intrapartum cesarean delivery in the smaller weight group compared with those in the similar weight group were not increased (3.4 vs. 4.5%; crude OR 0.75; 95%CI 0.23-2.42).

CONCLUSION

The difference between current estimated fetal weight and previous birth weight plays an important role in assessing the risk of intrapartum cesarean delivery.

KEY POINTS

· Estimated fetal weight compared with previous birth weight is an important factor.. · Cesarean delivery is infrequent if estimated fetal weight is similar to previous birth weight.. · Larger estimated fetal weight greater than the previous birth weight is associated with cesarean delivery..