Maternal age and fetal loss: population based register Linkage study

Objective To estimate the association between maternal age and fetal death (spontaneous abortion, ectopic pregnancy, stillbirth), taking into account a woman's reproductive history. Design Prospective register linkage study. Subjects All women with a reproductive outcome (live birth, stillbirth, spo ntaneous abortion leading to admission to hospital, induced abortion, ectop ic pregnancy, or hydatidiform mole) in Denmark from 1978 to 1992; a total o f 634 272 women and 1 221 546 pregnancy outcomes. Main outcome measures Age related risk of fetal loss, ectopic pregnancy, an d stillbirth, and age related risk of spontaneous abortion stratified accor ding to parity and previous spontaneous abortions. Results Overall, 13.5% of the pregnancies intended to be carried to term en ded with fetal loss. At age 42 years, more than half of such pregnancies re sulted in fetal loss. The risk of a spontaneous abortion was 8.9% in women aged 20-24 years and 74.7% in those aged 45 years or more. High maternal ag e was a significant risk factor for spontaneous abortion irrespective of th e number of previous miscarriages, parity, or calendar period. The risk of an ectopic pregnancy and stillbirth also increased with increasing maternal age. Conclusions Fetal loss in high in women in their late 30s or older; irrespe ctive of reproductive history. This should be taken into consideration in p regnancy planning and counselling.