Dr Ole Christiansen, a consultant registrar at the Rigshospitalet Fertility Clinic in Copenhagen, Denmark, told the annual conference of the European Society of Human Reproduction and Embryology, that giving birth to a boy first was not only a risk factor for subsequent miscarriages, but for women who suffered unexplained secondary recurrent miscarriages (SRM) it could mean that they never managed to carry a child to full term again unless doctors gave them appropriate treatments.
Dr Christiansen said: "Giving birth to a son is known already to be a prognostically negative factor in many obstetrical complications. Therefore we wanted to assess the impact of the gender of the first child on the outcome of subsequent pregnancies among patients with unexplained secondary recurrent miscarriages."
He studied 204 SRM patients admitted to clinics between 1986 and 2000, and obtained information on subsequent pregnancy outcome in 181 patients admitted before 2000. Among the patients admitted before 2000, only 54.4% of those who gave birth to a boy in their first pregnancy had given birth to a second live baby by January 2002, compared with 73% of women whose first child was a girl.
Amongst a subset of women who did manage to have a second child after a series of miscarriages, those whose first child was a boy had an average of 3.9 miscarriages before achieving a second birth, while women whose first child was girl had 3.5 miscarriages before delivery of a second child a small but statistically significant difference. Average birth weights of the second children tended to be 181g higher where the first-born was a girl.
Dr Christiansen said: "Our study shows that the majority (54.4%) of those
Contact: Emma Mason
European Society for Human Reproduction and Embryology