Prospective, randomized study to evaluate the success rates using hCG, vaginal progesterone or a combination of both for luteal phase support

Background A prospective study was done to compare the efficacy of luteal p hase support (LPS) using either three times hCG (group I, n=77), hCG on the day of embryo transfer (ET) in combination with daily vaginal progesterone (group II, n=62) or vaginal progesterone only (group III, n=70). Method. All patients were treated using the long luteal protocol for contro lled ovarian stimulation in an IVF (in vitro fertilization) cycle. Patients were randomized to one of these groups when estradiol was <2500 pg/ml and less than 12 oocytes were retrieved (low risk groups). If estradiol was <gr eater than or equal to> 2500 pg/ml and/or at least 12 oocytes were retrieve d (high risk groups), patients were randomized to receive either hCG in com bination with daily vaginal progesterone (group IV, n=83) or progesterone o nly (group V, n=121). For vaginal progesterone Utrogest(R) was used (three times daily two capsules containing 100 mg progesterone, 600 mg/d). Results. Demographic data were comparable within the high risk and low risk groups. However, for unknown reasons the fertilization rate was significan tly higher in group V (48%) compared to group IV (40%) (p<0.05), leading to a significantly higher cumulative embryo score. There were no statisticall y significant differences with regard to the main outcome parameter, the cl inical ongoing pregnancy rate in the low risk groups (14.3%, 14.5%, 11.4%) and the high risk groups (21.0%, 21.5%), respectively. Using a standardized discomfort scale, there were more complaints towards the end of the luteal phase in the groups receiving hCG only or an additional injection of hCG, when compared to the progesterone only groups. Conclusion. Progesterone only for luteal phase support leads to the same cl inical ongoing pregnancy rate as hCG, but has no impact on the comfort of t he patient.