Pituitary suppression regimens in poor responders undergoing IVF treatment: a systematic review and meta-analysis

Many randomized trials have evaluated the use of various pituitary suppression regimens to improve outcome of poor responders undergoing IVF treatment. A systematic review was conducted of the trials of gonadotrophin-releasing hormone (GnRH) agonist long regimen, GnRH agonist short regimen, GnRH antagonist regimen, as well as other pituitary suppression regimens in poor responders undergoing IVF/intracytoplasmic sperm injection (ICSI) treatment. The search included MEDLINE, EMBASE, Cochrane Library, National Research Register and ISI proceedings, and all randomized controlled trials comparing the various pituitary suppression regimens in poor responders were included. Study selection, quality appraisal and data extraction were performed independently and in duplicate. The main outcome measures were number of oocytes retrieved, cycles cancelled before oocyte retrieval and pregnancy rates. A total of 680 women considered as poor responders undergoing IVF/ICSI treatment were included in nine randomized controlled trials. The quality of these studies was variable: for example, only three of the studies had clear evidence of allocation concealment. Meta-analyses of the results of the studies did not show a consistent benefit for any one pituitary suppression regimen over the other regimens in improving outcome measures. Currently available evidence does not favour any one pituitary suppression regimen for women with poor ovarian response undergoing IVF/ICSI treatment.