title: Sex ratio and twinning in women with hyperemesis or pre-eclampsia.
abstract: We examined twinning and fetal gender in births of women with a hospital diagnosis of pre-eclampsia or hyperemesis. We also investigated sex ratio in infants whose mothers had had hyperemesis or pre-eclampsia in a different pregnancy. From all the hospitalized cases in Denmark between 1980 and 1996 we extracted 6,227 births with hyperemesis and 24,764 with pre-eclampsia. Twins were more frequent in pregnancies with either condition. The male to female sex ratio was 1.04 (95%CI = 1.02-1.05) in the reference population, 0.87 (95% CI = 0.82-0.91) in births with hyperemesis, and 1.10 (95% CI = 1.07-1.12) in births with pre-eclampsia. Women with pre-eclampsia had slightly more males also in non-affected pregnancies.
authors.affiliation: The Danish Epidemiology Science Centre at the Department of Epidemiology and Social Medicine- Aarhus University, DK 8000 Aarhus C, DK.
authors.forename: O
authors.initials: O
authors.lastname: Basso
authors.forename: J
authors.initials: J
authors.lastname: Olsen
mesh_terms: D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D006939:Hyperemesis Gravidarum / Q000453:epidemiology*; D007231:Infant, Newborn; D011225:Pre-Eclampsia / Q000453:epidemiology*; D011247:Pregnancy; D012744:Sex Ratio; D014427:Twins / Q000706:statistics & numerical data*