Increasing Birth Weight above 4,000 Grams Is Associated with Adverse Outcomes among Births without Diabetes

Area of Science:

• Obstetrics and Gynecology
• Perinatal Medicine
• Maternal-Fetal Medicine

Background:

• Birth weight is a critical indicator of fetal well-being.
• Macrosomia (high birth weight) is linked to adverse obstetric complications.
• The influence of maternal factors like BMI and GWG on macrosomia-related risks requires further investigation.

Purpose of the Study:

• To evaluate the association between increasing birth weight (above 4,000g) and adverse obstetric outcomes.
• To explore the impact of maternal prepregnancy BMI and gestational weight gain (GWG) on these risks.
• To analyze these associations in births not complicated by diabetes.

Main Methods:

• Retrospective cohort study of singleton, non-anomalous live births (2012-2021) in the US.
• Exclusion of births with diabetes or birth weights <3,000g.
• Stratification into birth weight categories (3,000-3,999g, 4,000-4,499g, 4,500-4,999g, ≥5,000g) and analysis by prepregnancy BMI and GWG.

Main Results:

• Over 23 million births analyzed; higher birth weights correlated with increased risks of cesarean delivery, blood transfusion, hysterectomy, ICU admission, and anal sphincter injury.
• Adverse neonatal outcomes also rose with increasing birth weight.
• Stratification revealed heightened risks in higher birth weight categories, especially with maternal obesity or excessive GWG.

Conclusions:

• Birth weights exceeding 4,000g are associated with progressively higher risks of adverse perinatal outcomes, independent of diabetes.
• Maternal obesity and excessive GWG exacerbate the risks associated with higher birth weights.
• These findings underscore the importance of monitoring and managing maternal weight factors in relation to fetal growth.