Causes of stillbirth at different gestational ages in singleton pregnancies

OBJECTIVE: To compare causes of stillbirth in preterm and term pregnancies. DESIGN: Cohort study. SETTING: All delivery wards in Stockholm, 1998-2009. POPULATION: Stillbirths from singleton pregnancies of gestational age ≥22(+0) (n = 1089) extracted from a web-based database including all stillbirths in the major Stockholm area since 1998. METHODS: The parents of the stillborns were all offered an extensive standardized investigation. The causes of death were assigned in a perinatal audit using the Stockholm classification of stillbirth. Singleton stillbirths were divided into preterm (gestational week 22(+0) -36(+6) ) and term/post-term (gestational week ≥37(+0) ). The term/post-term group was subdivided into term (gestational week 37(+0) -40(+6) ) and post-term stillbirths (gestational week ≥41(+0) ). MAIN OUTCOME MEASURE: Causes of stillbirth at different gestational ages. RESULTS: A higher proportion of placental abruption and preeclampsia/hypertension was seen in preterm stillbirths compared with term/post-term stillbirths, which instead had a higher proportion of umbilical cord complications and infection. Infection was more common in post-term than term stillbirths (46.5 vs. 19.8%, p < 0.001). CONCLUSION: Increased knowledge of causes of stillbirth in different gestational ages may be valuable in developing strategies for prevention of fetal death. The high proportion of infection in post-term stillbirths could be clinically important and warrants further studies.