title: Preemption dimensional study for obtaining statistically significant results for the variation of gamma-glutamyl-transferase during ovarian stimulation.
abstract: BACKGROUND
  Ovarian stimulation with gonadotropins/ gonadotropin releasing factor agonists (a-GnRH), largely used currently for infertility treatment, can induce hepatic effects, demonstrated only in animals or in women with hyperstimulation syndrome.
  
  
  OBJECTIVE
  We wanted to estimate the number of included patients for which the variation of gamma-glutamyl-transferase (GGT) during and due to ovarian stimulation could be sustained by statistic validation.
  
  
  METHODS
  In 23 consecutive patients, aged 23-45 years (mean 32.6 +/- 7.4 years) included in a fertility program, busereline, an a-GnRH was started the first day of the cycle and followed from the 14th ay with human menopausal gonadotropin. Ovulation was triggered with human chorionic gonadotropin. GGT was measured in the serum the first day (control), in the 14th, 19th, 24th day, the day before the triggering of the ovulation and two days after that. The statistic study used a distribution analysis (Student t test)--BMDP, SAS 6.0 and EpiInfo 5 software and calculated the necessary number of measurements in order to obtain significant (95%) variation for GGT (actual and = 5%).
  
  
  CONCLUSIONS
  The proper number of determinations which statistically support a possible significant difference is 29-38 and 46 for a 5% difference. The considered suppositions are able to support a correct estimation.
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, Ovidius University, Bd. Tomis 143, 900591 Constanta, Romania. vladtica@datanet.ro
authors.forename: Vlad I
authors.initials: VI
authors.lastname: Tica
authors.forename: Pierre
authors.initials: P
authors.lastname: Mares
authors.forename: Ovidiu
authors.initials: O
authors.lastname: Teren
authors.forename: Irina
authors.initials: I
authors.lastname: Tica
authors.forename: Andrei A
authors.initials: AA
authors.lastname: Tica
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007247:Infertility, Female / Q000201:enzymology* / Q000628:therapy; D008875:Middle Aged; D010062:Ovulation Induction; D015203:Reproducibility of Results; D018401:Sample Size; D005723:gamma-Glutamyltransferase / Q000097:blood*
chemical_list: D005723:gamma-Glutamyltransferase