Objective: To assess the difference in pregnancy outcomes among triplet pregnancies that spontaneously reduce, selectively reduce, or continue as triplets.Design: Descriptive study.Materials and Methods: A retrospective chart analysis of 183 triplet pregnancies conceived under the care of the Center for Fertility and Reproductive Health at Harvard Vanguard Medical Associates from 1990–2002. All pregnancies showing three gestational sacs on ultrasound in the first trimester were included in the study. Spontaneous reduction was defined as loss of one or more sacs during the first trimester. Multifetal pregnancy reduction (MFPR) was offered to all patients and performed at 12–14 weeks. Analysis was completed using the Statistical Package for the Social Sciences (SPSS).Results: Thirty-nine percent of the triplet pregnancies spontaneously reduced. Of the remainder, 53% chose MFPR pregnancies and 47% chose to continue the triplet pregnancy. Neonates of the women of who had MFPR had the highest gestational age at delivery (35 wks). Triplet pregnancies delivered at a mean of 32 wks. The women who had spontaneous reduction delivered at the earliest gestational age (31wks.) Tabled 1Conclusion: Analysis demonstrated that the three groups are very different in infant outcome. Findings in the spontaneous group were surprising and merit further investigation. Further data analysis will examine associations between other maternal and infant variables. Objective: To assess the difference in pregnancy outcomes among triplet pregnancies that spontaneously reduce, selectively reduce, or continue as triplets. Design: Descriptive study. Materials and Methods: A retrospective chart analysis of 183 triplet pregnancies conceived under the care of the Center for Fertility and Reproductive Health at Harvard Vanguard Medical Associates from 1990–2002. All pregnancies showing three gestational sacs on ultrasound in the first trimester were included in the study. Spontaneous reduction was defined as loss of one or more sacs during the first trimester. Multifetal pregnancy reduction (MFPR) was offered to all patients and performed at 12–14 weeks. Analysis was completed using the Statistical Package for the Social Sciences (SPSS). Results: Thirty-nine percent of the triplet pregnancies spontaneously reduced. Of the remainder, 53% chose MFPR pregnancies and 47% chose to continue the triplet pregnancy. Neonates of the women of who had MFPR had the highest gestational age at delivery (35 wks). Triplet pregnancies delivered at a mean of 32 wks. The women who had spontaneous reduction delivered at the earliest gestational age (31wks.) Tabled 1 Conclusion: Analysis demonstrated that the three groups are very different in infant outcome. Findings in the spontaneous group were surprising and merit further investigation. Further data analysis will examine associations between other maternal and infant variables.