THE BENEFITS OF MID-LUTEAL ADDITION OF HUMAN CHORIONIC-GONADOTROPIN IN IN-VITRO FERTILIZATION USING A DOWN-REGULATION PROTOCOL AND LUTEAL SUPPORT WITH PROGESTERONE

Luteal support is essential in in-vitro fertilization (IVF) when long- acting gonadotrophin-releasing hormone agonist (GnRHa) is used, Becaus e progesterone lacks luteotrophic stimulation, it seems to be the drug of choice in cases with an increased risk of ovarian hyperstimulation syndrome (OHSS), The aim of this study was to assess the beneficial e ffect of the mid-luteal addition of human chorionic gonadotrophin (HCG ) in IVF, using a down-regulation protocol and luteal support with pro gesterone, in a prospective randomized study, The study included 170 I VF cycles down-regulated with long-acting GnRHa which were supported w ith 50 mg/day progesterone i.m, during the luteal phase, Patients were evaluated in the mid-luteal period, Those without clinical signs of O HSS, oestradiol concentrations <1000 pg/ml and progesterone concentrat ions <50 ng/ml were randomly allocated to either the addition of 2500 IU HCG (HCG+ group) or no HCG (HCG- group), End luteal phase progester one concentrations among nonpregnant patients were used to assess the contribution of exogenous progesterone and to categorize pregnancies a ccording to their corpus luteum function, Similar low OHSS (2.7 and 1. 8%) and pregnancy (30 and 29%) rates were observed in the HCG+ and HCG - groups respectively, Of the 26 pregnancies in the HCG+ cases, there was only one case with reduced corpus luteum function, compared with 1 2 of the 25 pregnancies among HCG- patients, Cases with reduced corpus luteum function required continuous progesterone support and presente d loner beta HCG concentrations and a higher rate of adverse pregnancy outcome, We conclude that mid-luteal HCG addition does not affect pre gnancy rate, but in fact helps to preserve corpus luteum function and avoids the need for further supplementation during early pregnancy.