title: Maternal serum human chorionic gonadotropin levels in twin pregnancies.
abstract: Introduction of combined screening with maternal serum alpha-fetoprotein and human chorionic gonadotropin (MShCG) assays for fetal chromosome defects requires establishment of the normal range for twins. This report documents that the normal range for MShCG between 15 and 19 weeks in twin gestations was 1.84-2.41 multiples of the singleton median. Of the 192 twin pregnancies studied, 31.7 and 47.9 per cent had MShCG values greater than or equal to 2.5 and greater than or equal to 2.0 multiples of the singleton median, respectively.
authors.affiliation: Center for Human Genetics, Boston University School of Medicine, MA.
authors.forename: L M
authors.initials: LM
authors.lastname: Nebiolo
authors.forename: W B
authors.initials: WB
authors.lastname: Adams
authors.forename: S L
authors.initials: SL
authors.lastname: Miller
authors.forename: A
authors.initials: A
authors.lastname: Milunsky
mesh_terms: D006063:Chorionic Gonadotropin / Q000097:blood*; D005260:Female; D005615:Freezing; D006801:Humans; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011272:Pregnancy, Multiple / Q000097:blood*; D012016:Reference Values; D012044:Regression Analysis
chemical_list: D006063:Chorionic Gonadotropin