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Sex ratio and twinning in women with hyperemesis or pre-eclampsia

O Basso1, J Olsen

  • 1The Danish Epidemiology Science Centre at the Department of Epidemiology and Social Medicine- Aarhus University, DK 8000 Aarhus C, DK.

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.

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