Study question

Does additional low dose hCG supplementation with vaginal progesterone gel is equally effective with intramuscular progesterone as luteal phase support of COH IVF cycles?

Summary answer

In COH IVF cycles, additional low dose hCG supplementation with vaginal progesterone gel makes similar pregnancy rate with intramuscular progesterone as luteal phase support.

What is known already

In a past meta-analyses, clinical pregnancy and delivery rates were significantly improved with intramuscular (IM) progesterone as compared with vaginal progesterone. On the other hand, in some recent RCTs and meta-analyses provided some evidence that no difference existed regarding the clinical pregnancy rate between vaginal progesterone and IM progesterone for LPS. However, many clinicians still prefer IM progesterone to vaginal progesterone due to concern of decreased pregnancy rate with vaginal progesterone.

Study design, size, duration

This retrospective cohort study included 543 women undergoing IVF between January 2011 and December 2012.

Participants/materials, setting, methods

We retrospectively reviewed 543 patients undergoing IVF using GnRH agonist and antagonist protocols. After COH and oocyte aspiration, women received IM progesterone only (Group A) or vaginal progesterone with additional low dose hCG three times (Group B) (1000 IU, OPU day, ET day, ET+3 day).

Main results and the role of chance

349 patient received IM progesterone only as LPS and vaginal progesterone with low dose hCG was given to 194 women. In each group, age (35.9±4.28 vs. 35.06±4.37), endometrial thickness (10.39±2.11 vs. 10.33±2.13), number of transferred embryos (2.0 vs2.0) and percentage of top quality embryo (60.7% vs. 59.3%) did not show significant difference. There were no significant differences between two groups in the pregnancy rate [52.7%(184/349) vs. 49.0%(95/194), P=0.2], spontaneous abortion rate[9.8%(18/184) vs. 8.4%(8/95), P=0.3], ongoing pregnancy rate [47.6%(166/349) vs. 44.8%(87/194), P=0.14].

Limitations, reasons for caution

This is a retrospective study. A prospective randomized study would have minimized potential limitations. And we don’t have comparison group using vaginal progesterone only as LPS due to previous experience of decreased pregnancy rate with vaginal progesterone only [PR 35.7%(5/14)].

Wider implications of the findings

The intravaginal route of progesterone supplementation in IVF has gained wide application as a first choice luteal support regimen, mainly due to comfort and effectiveness of patient. In spite of some RCTs and meta-analyses proving efficacy of vaginal progesterone, many clinicians have met episode of vaginal bleeding before pregnancy test and some have experienced decreased pregnancy rate. With additional low dose hCG, vaginal progesterone could be more secure LPS and really equivalent to IM progesterone.

Study funding/competing interest(s)
Funding by hospital/clinic(s)

Mamapapa&baby Obstetrics & Gynecology clinic