A randomized comparison of the efficacy, side effects and patient convenience between vaginal and rectal administration of Cyclogest(®) when used for luteal phase support in ICSI treatment.

Purpose: This study compares the efficacy, side effects and patient convenience of vaginal and rectal routes of administration of progesterone suppositories (Cyclogest) when used for luteal phase support during in vitro fertilization cycles, through the use of antagonist protocols.

Methods: 147 patients who underwent intra-cytoplasmic sperm injection cycle were randomized on the day of the embryo transfer (ET) by a computer-generated randomization program to receive 400 mg of Cyclogest either vaginally or rectally twice daily for up to 8 weeks. A pregnancy test was conducted 2 weeks after embryo transfer. If the pregnancy test was negative, the application was discontinued. On day 14th after embryo transfer, patient's acceptability and side effects were assessed using a questionnaire which was given to the patients on the day of ET prior to performing the pregnancy test. The clinical pregnancy rate at the 8th week of gestation and the level of luteal progesterone were evaluated.

Results: There were no substantial differences in the demographics or other characteristics between the two groups. There were no significant differences in serum P concentration 6 days after ET, the clinical pregnancy and abortion rates. The difficulty of administration route, the discomforts experienced following administration, and the proportion leaking out on the 14th day were similar between the two groups. Significantly more patients administering the medication per vagina had perineal irritation (21.3 vs. 2.2 %). The prevalence of tenesmus (35.1 vs. 21.1 %) and rectal itching (26.7 vs. 2.8 %) were significantly more in rectal route.

Conclusions: This study demonstrates that the efficacy of Cyclogest is similar when administered via both the vaginal and rectal routes. Although their side effects differ, the ease of administration for patients and their preference are similar.