9 research outputs found
Twin births, sex of children and maternal risk of ovarian cancer: a cohort study in Norway
In a follow-up of 1â208â001 women aged 20â74 years, no significant association was found between twin births (112 cases) and risk, though those with twin girls had a non-significantly higher risk than those with singleton births; among the latter, those with girls only had a higher risk of endometrioid tumours (incidence rate ratio 1.35; 95% confidence interval 1.03â1.76, based on 475 cases) than women with boys only