title: Management of multiple pregnancy: prenatal care-part I.
abstract: Over the past 20 years, the number and rate of multiple births have dramatically increased in the United States. The rise in multiple births is mainly attributable to the increased use of ovulation-inducing drugs and the newly developed assisted reproductive technologies such as in vitro fertilization. Multifetal gestation is associated with an increased risk of perinatal morbidity and mortality. Multiple births account for an increasing percentage of low-birth-weight infants, preterm births, and infant mortality. In this section, we address the management of the multifetal pregnancy, focusing on the maternal physiology, the diagnosis, the pregnancy outcomes, and the antenatal management of multiple gestation.
  
  
  BACKGROUND
  Obstetricians & Gynecologists, Family Physicians
  
  
  OBJECTIVE
  After completion of this article, the reader should be able to describe the effects of the rising rate of multiple pregnancies on perinatal morbidity and mortality, to recall the complications of diagnosing and treating abnormalities of multiple pregnancies, and to list the many changes that occur in both the mother and the fetuses in multiple pregnancies.
authors.affiliation: Department of OB/GYN Naval Medical Center Portsmouth, MFM Division, Norfolk, Virginia 23511, USA. mfmayres@cox.net
authors.forename: Allen
authors.initials: A
authors.lastname: Ayres
authors.forename: Timothy R B
authors.initials: TR
authors.lastname: Johnson
mesh_terms: D000328:Adult; D036861:Delivery, Obstetric; D005260:Female; D006801:Humans; D011247:Pregnancy / Q000502:physiology*; D011248:Pregnancy Complications / Q000209:etiology* / Q000628:therapy; D011256:Pregnancy Outcome; D011272:Pregnancy, Multiple; D011295:Prenatal Care; D012307:Risk Factors; D016216:Ultrasonography, Prenatal