title: Increased day 15-17 serum pro-alphaC inhibin levels specific to successful pregnancy.
abstract: In early pregnancy, serum levels of the luteal-derived hormone pro-alphaC inhibin peak by the second week after conception. Whether this early rise is biologically important and a consistent feature of only successful pregnancy is unknown. We undertook a prospective cross-sectional study to determine whether serum pro-alphaC inhibin levels at d 15-17 are predictive of a successful clinical in vitro fertilization pregnancy and compared levels between fresh embryo transfer (ET) and frozen-thawed ET. Median (95% confidence interval) pro-alphaC inhibin levels were 68 (57-76) pg/ml in 204 women who did not become clinically pregnant after ET, significantly lower than in either 90 women who became clinically pregnant after fresh ET and who had 3139 (1684-4220) pg/ml or in 39 women with a successful frozen ET who had 877 (678-1111) pg/ml. Pro-alphaC was highly sensitive and specific in predicting clinical pregnancy success but did not improve on the performance of human chorionic gonadotropin. Pro-alphaC inhibin levels were not correlated with progesterone or human chorionic gonadotropin. Levels were no higher in singleton compared with multiple pregnancies and did not increase across gestation, suggestive of a luteal source. The increase in circulating pro-alphaC inhibin in very early pregnancy is highly specific to clinical pregnancy, suggesting a possible biological role in early gestation.
authors.affiliation: Department of Obstetrics and Gynaecology, Monash University, Monash Medical Centre, 246 Clayton Road, Clayton, Victoria 3168, Australia. Stephen.Tong@med.monash.edu.au
authors.forename: Stephen
authors.initials: S
authors.lastname: Tong
authors.forename: Luk
authors.initials: L
authors.lastname: Rombauts
authors.forename: Annegien
authors.initials: A
authors.lastname: Mulder
authors.forename: Budi
authors.initials: B
authors.lastname: Marjono
authors.forename: Joseph L
authors.initials: JL
authors.lastname: Onwude
authors.forename: Euan M
authors.initials: EM
authors.lastname: Wallace
mesh_terms: D000328:Adult; D006063:Chorionic Gonadotropin / Q000097:blood; D003430:Cross-Sectional Studies; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D020249:Hormone Replacement Therapy; D006801:Humans; D007265:Inhibins / Q000097:blood*; D011247:Pregnancy; D011374:Progesterone / Q000097:blood; D011446:Prospective Studies; D011498:Protein Precursors / Q000097:blood*
chemical_list: D006063:Chorionic Gonadotropin; D011498:Protein Precursors; C095971:inhibin-alpha subunit precursor; D011374:Progesterone; D007265:Inhibins