Table 2 Relative risk of breast cancer, comparing primiparous women who had pre-eclampsia or gestational hypertension in pregnancy, and primiparous women who were normotensive, by gender of the offspring

From: The negative association between pre-eclampsia and breast cancer risk may depend on the offspring's gender

Characteristics of pregnancy Primiparous women Breast cancer Relative risk (95% CI)
All pregnancies
 Normotensive 164 091 1795 1.0 (Reference)
 Pre-eclampsia or hypertension 11 945 121 0.75a (0.62 to 0.91)
Male offspring
 Normotensive 84 274 908 1.0 (Reference)
 Pre-eclampsia or hypertension 6199 51 0.62b (0.47–0.82)
Female offspring
 Normotensive 79 817 887 1.0 (Reference)
 Pre-eclampsia or hypertension 5746 70 0.92b (0.72–1.18)
  1. aAdjusted for maternal age, age at birth, marital status, and offspring gender.
  2. bAdjusted for maternal age, age at birth, and marital status.
  3. CI = confidence interval.
  4. Significance test for interaction between pre-eclampsia and offspring gender, P=0.05.