title: Prolonged fetal ritodrine exposure and immediate neonatal outcome.
abstract: Ritodrine hydrochloride was administered over a period of two years to a total of 200 women in premature labor. One hundred sixty-two (81 per cent) of the women carried pregnancy to 35 weeks or longer. To determine the effect of ritodrine on the neonates, the duration and amount of exposure, onset of exposure, and interval between cessation of exposure and delivery were correlated with gestational age, birth weight, Apgar scores, mortality, and the presence of hypoglycemia, hyperbilirubinemia, respiratory distress, and intrauterine growth retardation. Infants exposed for six weeks or more (long-term exposure) were significantly heavier than those exposed for shorter periods (short-term exposure), a difference that was possibly attributable to differences in gestational age at birth. Infants who were exposed as fetuses to ritodrine beginning at 30 weeks' or less gestation needed phototherapy more often than did infants whose fetal exposure began at after 30 weeks' gestation. Neither duration of exposure nor gestational age at birth was a significant factor in hyperbilirubinemia. Of infants delivered at or after 35 weeks' gestation, 32 (20 per cent) experienced early hypoglycemia; and 26 of these (81 per cent) were exposed up to the day of delivery. This outcome differed significantly from that of infants whose exposure stopped at least one week before delivery. In addition, respiratory distress syndrome was more common in those infants exposed up until delivery (34 of 36).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Pediatrics and Human Development, Michigan State University, East Lansing.
authors.forename: M N
authors.initials: MN
authors.lastname: Musci
authors.forename: S
authors.initials: S
authors.lastname: Abbasi
authors.forename: C
authors.initials: C
authors.lastname: Otis
authors.forename: R J
authors.initials: RJ
authors.lastname: Bolognese
mesh_terms: D001724:Birth Weight / Q000187:drug effects*; D005260:Female; D005865:Gestational Age; D006801:Humans; D007003:Hypoglycemia / Q000139:chemically induced*; D007231:Infant, Newborn; D008431:Maternal-Fetal Exchange; D007752:Obstetric Labor, Premature / Q000517:prevention & control; D011247:Pregnancy; D012127:Respiratory Distress Syndrome, Newborn / Q000139:chemically induced*; D012189:Retrospective Studies; D012312:Ritodrine / Q000009:adverse effects*; D013997:Time Factors
chemical_list: D012312:Ritodrine