the effectiveness of luteal phase support with cyclogest in ovarian stimulated intra uterine insemination cycles: a randomized controlled trial

background: controlled ovarian stimulation combined with intra uterine insemination (iui) is a convenient treatment of infertility with a success rate of 11%. the clinical observation and pattern of progesterone secretion in this method is suggestive of luteal phase defect and postulated as an implicating factor of treatment failure. objective: to investigate the efficacy of luteal phase support with intravaginal cyclogest in women undergoing controlled ovarian stimulation combined with intrauterine insemination. materials and methods: in this single-blinded clinical trial, 196 consecutively seen women eligible for the study protocol, were randomized to receive either intravaginal progesterone (cyclogest pessary, actavis) or no medication in luteal phase. blood samples were collected and serum progesterone level in 7th and 11th day of the cycle, biochemical and clinical pregnancy and luteal phase duration were compared in case and control groups. results: the mean age in case and control group was 28 and 27.9 years, respectively and the most frequent cause of infertility was unexplained. additionally, ovulatory dysfunction was the most common cause of female infertility in both groups. based on these variables, there was no statistically significant difference between the two groups. mean serum progesterone level in the case group were 48.34 and 34.24nmol/day on day 7 and 11 after insemination, respectively and both values were significantly higher than the control group. there was no difference between the two groups in terms of biochemical and clinical pregnancy. luteal phase duration in the case group was significantly longer than the control group. conclusion: luteal phase support by cyclogest pessary increases progesterone level and prolongs the luteal phase, but does not affect success rate of iui cycles in terms of achieving pregnancy.