title: Regulation of corpus luteum function.
abstract: The effects have been studied of different ovulation induction regimens [either clomiphene citrate or buserelin in combination with human menopausal gonadotrophin (HMG)] on the circulating concentrations of progesterone, oestradiol, relaxin and human chorionic gonadotrophin (HCG) during the first trimester of pregnancy. Ovulation induction with clomiphene resulted in elevated concentrations of gonadotrophins in both phases of the cycle, while during ovulation induction with buserelin, gonadotrophin concentrations were elevated in the follicular phase only. The concentrations of all corpus luteum products were greater in clomiphene pregnancies compared with spontaneous pregnancies, but only oestradiol and relaxin concentrations were greater in clomiphene pregnancies compared with buserelin pregnancies. The concentrations of HCG were significantly reduced in clomiphene pregnancies compared to natural pregnancies. Relaxin concentrations were significantly higher from 7 weeks gestation in buserelin compared with spontaneous pregnancies, while progesterone, oestradiol and HCG concentrations were not consistently different. Consistent associations were found between relaxin and HCG concentrations in spontaneous pregnancies and between the concentrations of relaxin and both progesterone and oestradiol in pregnancies achieved after ovulation induction.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Obstetrics and Gynaecology, Chelsea and Westminster Hospital, London, UK.
authors.forename: M R
authors.initials: MR
authors.lastname: Johnson
authors.forename: A A
authors.initials: AA
authors.lastname: Abbas
authors.forename: R
authors.initials: R
authors.lastname: Irvine
authors.forename: A F
authors.initials: AF
authors.lastname: Riddle
authors.forename: J Q
authors.initials: JQ
authors.lastname: Norman-Taylor
authors.forename: J G
authors.initials: JG
authors.lastname: Grudzinskas
authors.forename: W P
authors.initials: WP
authors.lastname: Collins
authors.forename: K H
authors.initials: KH
authors.lastname: Nicolaides
mesh_terms: D000328:Adult; D002064:Buserelin / Q000627:therapeutic use; D002452:Cell Count; D002996:Clomiphene / Q000627:therapeutic use; D003338:Corpus Luteum / Q000502:physiology*; D004958:Estradiol / Q000378:metabolism*; D005260:Female; D006801:Humans; D010062:Ovulation Induction; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011374:Progesterone / Q000378:metabolism*; D012065:Relaxin / Q000378:metabolism*; D014427:Twins
chemical_list: D002996:Clomiphene; D011374:Progesterone; D004958:Estradiol; D012065:Relaxin; D002064:Buserelin