Efficacy of progesterone support in the luteal phase following in-vitro fertilization and embryo transfer: meta-analysis of clinical trials.

The question of whether follicular aspiration of oocytes alters the quality of the luteal phase remains unanswered. Progesterone appears to be necessary for implantation and maintenance of an early intrauterine pregnancy and this partly has been the basis for recommending luteal phase supplementation with progesterone following oocyte retrieval. Although small increases in pregnancy rates were observed in several trials, such support with progesterone was not efficacious. However, none of the studies had sufficient statistical power to detect small improvements in pregnancy rate. Pooling the results of these trails using several methods of meta-analysis has allowed an overall effect of treatment to be calculated. This effect, as measured by the odds ratio, was not significant, indicating that there was insufficient evidence to recommend the routine use of progesterone to support the luteal phase after oocyte retrieval.