Maternal cardiac function at 35-37 weeks' gestation: relationship with birth weight

Area of Science:

• Obstetrics and Gynecology
• Maternal-Fetal Medicine
• Cardiovascular Physiology

Background:

• Neonatal birth weight is a critical indicator of infant health.
• Predicting small-for-gestational-age (SGA) and large-for-gestational-age (LGA) neonates is crucial for appropriate perinatal care.
• Maternal cardiovascular parameters may influence fetal growth and development.

Purpose of the Study:

• To investigate the association between maternal cardiovascular parameters and neonatal birth weight.
• To assess the utility of maternal cardiovascular parameters in enhancing the prediction of SGA and LGA neonates.

Main Methods:

• Maternal characteristics, medical history, and cardiovascular parameters were recorded in 2835 singleton pregnancies.
• Cardiovascular parameters were normalized to median values (MoM).
• Regression analyses were used to correlate cardiovascular parameters with birth-weight Z-scores and predict SGA/LGA outcomes.

Main Results:

• Significant associations were found between maternal cardiac output and heart rate (positive) and total peripheral resistance and mean arterial pressure (MAP) (negative) with neonatal birth-weight Z-score.
• Maternal cardiovascular parameters differed between pregnancies resulting in SGA and LGA neonates.
• While maternal factors and fetal biometry did not improve SGA prediction, adding maternal heart rate showed a small but significant improvement for LGA prediction.

Conclusions:

• Maternal cardiovascular function is closely related to fetal demands, as evidenced by associations with birth weight.
• Assessing maternal cardiovascular parameters at 35-37 weeks' gestation offers limited improvement for screening SGA or LGA neonates when combined with existing methods.
• Maternal heart rate may offer a marginal benefit in predicting LGA neonates.