Risk of Instrumental Delivery in Maternal Obesity: Estimates With Measures of Effect Size

Area of Science:

• Obstetrics and Gynecology
• Maternal-Fetal Medicine
• Public Health

Background:

• Obesity (body mass index ≥30 kg/m2) is a widespread health issue in the US, linked to adverse pregnancy outcomes.
• Previous studies on maternal obesity and instrumental delivery have yielded conflicting results, often due to statistical limitations.
• Effect size measures are crucial for accurately assessing the clinical significance of risk factors in obstetrics.

Purpose of the Study:

• To quantify the association between maternal obesity and the requirement for instrumental vaginal delivery using effect size measures.
• To evaluate the clinical impact of maternal obesity on instrumental delivery rates, addressing limitations of prior frequentist analyses.
• To determine if maternal obesity is an independent risk factor for instrumental delivery.

Main Methods:

• Retrospective analysis of parturients (≥18 years) in active labor from January 2018 to May 2019.
• Collection and analysis of patient demographics, comorbidities, and obstetric parameters.
• Utilized risk differences and generalized linear models to standardize effect sizes and assess clinical impact.

Main Results:

• Parturients with obesity had higher incidences of chronic hypertension, gestational hypertension, preeclampsia, chronic diabetes, and reactive airway disease.
• Maternal obesity showed a risk difference for instrumental delivery in cases of shoulder dystocia, but not with oxytocin induction or in nulliparous patients.
• Regression analysis indicated that maternal obesity did not clinically influence the need for instrumental delivery.

Conclusions:

• Maternal obesity was not found to have a significant clinical impact on the overall need for instrumental vaginal delivery.
• The study highlights the importance of effect size measures in understanding the clinical relevance of risk factors in childbirth.
• Further research may explore specific subgroups or interventions to clarify the nuanced relationship between obesity and delivery outcomes.