Pregnancy outcome in hyperemesis gravidarum--the role of fetal gender

Abstract

Objective: To determine whether the incidence, severity and effects of hyperemesis gravidarum (HEG) are related to fetal gender.

Method: A retrospective study of all pregnant women who were admitted with the diagnosis of HEG between 1994 and 2008 (N = 545). The association between fetal gender and pregnancy outcome in pregnancies complicated by HEG was compared to that of a control group of women with singleton pregnancies matched by maternal age and parity in a 3:1 ratio (N = 1635).

Results: Women with HEG with a female fetus were younger (28.2 ± 4.8y versus 29.5 ± 5.5y, p = 0.003), were admitted earlier in pregnancy for HEG (admission < 10w: 62.3% versus 53.4%, p = 0.04), and were more likely to require TPN support (35.6% versus 26.9%, p = 0.03) compared to women with HEG having a male fetus. Compared to controls, women with HEG were more likely to have a female rather than a male fetus (odds ratio (OR) = 1.20) although this difference reached statistical significance only for the subgroup of women with HEG who were admitted prior to 10 weeks of gestation (OR = 1.40, 95%-confidence interval (CI) 1.03-1.70) or who required TPN support (OR = 1.593, 95% CI 1.15-2.0263). The presence of a male fetus in pregnancies complicated by HEG was associated with an increased risk for preterm delivery (OR = 0.49, 95% CI 0.27-0.87), and composite neonatal morbidity (OR = 0.38, 95% CI 0.20-0.74).

Conclusion: Although HEG appears to be more common and more severe in the presence of a female fetus, male fetuses appear to be more susceptible to the adverse effects of HEG on pregnancy outcome.