Adverse Neonatal Outcomes in Pregnant Women with Severe Vomiting: A Meta-Analysis

We aimed to systematically evaluate the risk of negative effect for newborns born to expectant mothers with severe vomiting in terms of birth weight, premature delivery, low Apgar score, and NICU hospitalization.

We conducted a systematically search for relevant studies on PubMed, Embase, Cochrane Library, and CNKI databases, using Newcastle-Ottawa Scale to evaluate research quality, and RevMan 5.3 software for meta-analysis from 2009 to 2022. The main outcome measures were: Low-birth weight, preterm delivery, low Apgar score and growth restriction.

In 9 studies, the risk of Low birth weight in hyperemesis pregnant women was increased, and the random effect model was OR 2.38 (95% CI 0.43 to 13.13). The heterogeneity of the study was high (I²=100%). Four studies showed an increased risk of low Apgar scores, with an OR of 2.69 (95% CI 0.30 to 24.48), and high heterogeneity (I²=95%). The risk of premature birth in 5 papers is equivalent, with an OR of 0.93 (95% CI 0.71 to 1.22) and low heterogeneity (I²=6%). The risk of growth restriction was higher in 7 papers, with an OR of 1.31 (95% CI 0.93 to 1.85) and lower heterogeneity (I²=29%). Subgroup analysis showed that heterogeneity mainly stemmed from differences in the definition of hyperemesis.

Pregnant women with severe vomiting have a higher risk of giving birth to babies with low birth weight and low Apgar scores, and a higher risk of giving birth to babies with growth restriction, but the risk of premature birth is comparable.