Received April 10, 2020
Accepted October 20, 2020

Background: Luteal phase defect in patients undergoing assisted reproductive technology (ART) is a sign of insufficiency of uterine cavity to implant embryo in proper time due to insufficient progesterone effects on the endometrium. Purpose: To compare the success rate and side effects of subcutaneous progesterone with vaginal progesterone used to support luteal phase in ART cycles. Patients and Methods: In this prospective randomized study intracytoplasmic sperm injection (ICSI) was performed based on traditional method and the transfer of one or two 4-8 cell embryos was performed based on the patient's age on the third day of fertilization. Luteal phase support was started from the day of oocyte recovery and patients randomly received either a daily dose of 25mg subcutaneous progesterone (Prolutex, IBSA Switzerland) or a 400mg dose of vaginal progesterone (Cyclogest, Actoverco, United Kingdom) every 12 hours. If the pregnancy test with blood BHCG test was positive, support for the luteal phase continued until week 10 of gestation. The measured outcomes were the clinical, chemical and ongoing pregnancy rates as well as the rate of early abortion, patients’ acceptance, tolerance and satisfaction. Results: The results of the present study showed that there was no statistically significant difference between clinical, chemical and ongoing pregnancy rates as well as the rate of early abortion, and patients’ satisfaction when comparing the two treatment groups. Conclusion: Subcutaneous form of progesterone can be used in patients who are not willing to use vaginal progesterone with similar treatment results and patient satisfaction when compared to vaginal progesterone.