Multiple Gestation
Multiple Gestation
EpidemiologyThe incidence of multiple pregnancy in theUnited Statesis approximately3%ofall birthsand has been increasing annually due toassisted reproductive technologies (ART).Theincidence of monozygotic twins is constant atapproximately 4 in1,000births,whereastheincidence of dizygotic twins is higherin certainfamilies,AfricanAmericans,andincreases withmaternal age, parity, weight, height, andovulationinduction
Epidemiology. ◼ The incidence of multiple pregnancy in the United States is approximately 3% of all births and has been increasing annually due to assisted reproductive technologies (ART). The incidence of monozygotic twins is constant at approximately 4 in 1,000 births, whereas the incidence of dizygotic twins is higher in certain families, African Americans, and increases with maternal age, parity, weight, height, and ovulation induction
Intheabsence of fertilityagent use,tripletpregnanciesoccuratarate ofapproximately1in8,000births,andbirthsofhigherorderarerarer.Multiplegestationsincreasemorbidityand mortalityforboththe mothers and the fetuses;perinatal mortalityrates indevelopedcountriesrangefrom50to 100per1,000birthsfortwinsandfrom100to200per1,000birthsfortriplets
◼ In the absence of fertility agent use, triplet pregnancies occur at a rate of approximately 1 in 8,000 births, and births of higher order are rarer. Multiple gestations increase morbidity and mortality for both the mothers and the fetuses; perinatal mortality rates in developed countries range from 50 to 100 per 1,000 births for twins and from 100 to 200 per 1,000 births for triplets
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