Recurrence risk of stillbirth in a second pregnancy

Objective To examine the risk of recurrence of stillbirth in a second pregnancy. Design Retrospective cohort study. Setting Scotland, UK. Population All women who delivered their first and second pregnancies in Scotland between 1981 and 2005. Methods All women delivering for the first time between 1981 and 2000 were linked to records of their second pregnancy using routinely collected data from the Scottish Morbidity Returns. Women who had an intrauterine death in their first pregnancy formed the exposed cohort, whereas those who had a live birth formed the unexposed cohort. Main outcome measure Stillbirth in a second pregnancy. Results After adjusting for confounding factors, the odds of recurrence of stillbirth in a second pregnancy were found to be 1.94 (99% CI 1.29-2.92) compared with women who had had a live birth in their first pregnancy. Other factors associated with recurrence of stillbirth in a second pregnancy included placental abruption (adjusted OR 1.96; 99% CI 1.60-2.41), preterm delivery (adjusted OR 7.45; 99% CI 5.91-9.39) and low birthweight (adjusted OR 6.69; 99% CI 5.31-8.42). A Bayesian analysis using minimally informative normal priors found the risk of recurrence of stillbirth in a second pregnancy to be 1.59 (99% CI 1.10-2.33). Conclusions Women who have stillbirth in their first pregnancy have a higher risk of recurrence in their next pregnancy.