Adverse Maternal and Birth Outcomes in Women Admitted to Hospital for Hyperemesis Gravidarum: a Population-Based Cohort Study

BackgroundEvidence for risks of adverse maternal and birth outcomes in women with hyperemesis gravidarum (HG) is predominantly from small studies, unknown, or conflicting. MethodsA population-based cohort study using secondary health care records (Hospital Episode Statistics covering all of England from 1997 to 2012) was used to calculate odds ratios (OR) with 99% confidence intervals (CI) for the association between HG hospital admission and adverse outcomes, adjusting for maternal and pregnancy confounders. ResultsWithin 8 211 850 pregnancies ending in live births or stillbirths, women with HG had increased odds of anaemia (OR 1.28, 99% CI 1.23, 1.33), preeclampsia (OR 1.16, 99% CI 1.09, 1.22), eclampsia (OR 1.84, 99% CI 1.07, 3.18), venous thromboembolism antenatally (OR 1.94, 99% CI 1.57, 2.39 for deep vein thrombosis, and OR 2.54, 99% CI 1.89, 3.40 for pulmonary embolism) and post-partum. Odds of stillbirth (OR 0.77, 99% CI 0.66, 0.89) and post-term (OR 0.86, 99% CI 0.81, 0.92) delivery were decreased. Women were more likely to be induced (OR 1.20, 99% CI 1.16, 1.23), to deliver preterm (OR 1.11, 99% CI 1.05, 1.17), very preterm (OR 1.18, 99% CI 1.05, 1.32), or by caesarean section (OR 1.12, 99% CI 1.08, 1.16), to have low birthweight (OR 1.12, 99% CI 1.08, 1.17) or small for gestational age (OR 1.06, 99% CI 1.01, 1.11) babies and although absolute risks were small, their offspring were more likely to undergo resuscitation or neonatal intensive care. ConclusionHG may have important antenatal and postnatal consequences that should be considered in communications between health care professionals and women to best manage HG and prevent progression during pregnancy.