Perinatal Outcome of Singletons and Twins After Assisted Conceptions: A Systematic Review of Controlled Studies
Helmerhorst, Frans M.
Perquin, Denise A.M.
Keirse, Marc J.N.C.
BMJ: British Medical Journal 2004 January 31; 328(7434): 261- 264
OBJECTIVE: To compare the perinatal outcome of singleton and twin pregnancies between natural and assisted conceptions. DESIGN: Systematic review of controlled studies published 1985-2002. STUDIES REVIEWED: 25 studies were included of which 17 had matched and 8 had non-matched controls. MAIN OUTCOME MEASURES: Very preterm birth, preterm birth, very low birth weight, low birth weight, small for gestational age, caesarean section, admission to neonatal intensive care unit, and perinatal mortality. RESULTS: For singletons, studies with matched controls indicated a relative risk of 3.27 (95% confidence interval 2.03 to 5.28) for very preterm (