Pregnancy-related mortality among women with multifetal pregnancies

OBJECTIVE: To examine the relative risk of pregnancy-related mortality between multifetal pregnancies and singleton pregnancies. METHODS: We used data from the Centers for Disease Control and Prevention's Pregnancy Mortality Surveillance System to examine singleton and multifetal pregnancy-related deaths among women with a live birth or fetal death from 1979-2000. The plurality-specific (singleton or multifetal) pregnancy-based mortality ratio was defined as the number of pregnancy-related deaths per 100,000 pregnancies with a live birth. We analyzed the risk of death due to pregnancy for singleton and multifetal pregnancies by age, race, education, marital status, and cause of death. RESULTS: Of 4,992 pregnancy-related deaths in 1979-2000, 4.2% (209 deaths) were among women with multifetal pregnancies. The risk of pregnancy death among women with twin and higher-order pregnancies was 3.6 times that of women with singleton pregnancies (20.8 compared with 5.8). The leading causes of death were similar for women with singleton pregnancies and women with multifetal pregnancies: embolism, hypertensive complications of pregnancy, hemorrhage, and infection. CONCLUSION: Women with multifetal pregnancies have a significantly higher risk of pregnancy-related death than their counterparts with singleton pregnancies; this holds true for all women regardless of age, race, marital status, and level of education. LEVEL OF EVIDENCE: II-2.