NCT06870266

Comparison of Pregnancy Rates in Modified Natural Frozen Embryo Transfer (FET) Cycle After Luteal Support with GnRH Agonist Versus Progesterone: Prospective Randomized Study

Not yet recruiting EARLY_PHASE1 Last updated 5 March 2025

What this trial tests

EARLY_PHASE1 trial testing Nafarelin nasal spray in Ivf in 150 participants. Not yet recruiting.

Timeline

1 March 2025

Primary endpoint
1 March 2027

1 June 2027

Quick facts

Lead sponsor	Shaare Zedek Medical Center
Phase	EARLY_PHASE1
Status	Not yet recruiting
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	none
Primary purpose	treatment
Enrollment	150
Start date	1 March 2025
Primary completion	1 March 2027
Estimated completion	1 June 2027

Drugs / interventions tested

• Nafarelin nasal spray — full drug profile →
• Utrogestan®

Conditions studied

• Ivf — all drugs for Ivf →
• Frozen Embryo Transfer (FET) — all drugs for Frozen Embryo Transfer (FET) →

Sponsor

Shaare Zedek Medical Center

Who can join

Adults 18 to 40, female only, with Ivf or Frozen Embryo Transfer (FET). Patients with the condition only — healthy volunteers not accepted.

What's being measured

Primary outcomes are the specific endpoints the trial is designed to prove or disprove.

• clinical pregnancy rate
  Time frame: two months after ET
  positive fetal heart beat

Sponsor's own description

Background:

The capability to transfer frozen embryos reduces embryo loss following in vitro fertilization (IVF) and results in higher pregnancy rates compared to a single IVF cycle.

Endogenous progesterone from the corpus luteum, following frozen embryo transfer in natural or modified natural cycles, is expected to provide sufficient luteal support, as observed in spontaneous pregnancies. Nevertheless, research has demonstrated higher pregnancy success rates with additional luteal support. The current standard for luteal phase support involves vaginal progesterone administration.

Several case reports have indicated that administering a gonadotropin-releasing hormone (GnRH) agonist during the luteal phase does not compromise pregnancy continuation achieved through IVF and may, in fact, enhance implantation success.

Studies have shown that the luteal phase can be maintained with a GnRH agonist alone, without the need for progesterone supplementation.

A recent prospective randomized controlled trial compared standard progesterone support with GnRH agonist support in fresh embryo transfers. The group receiving GnRH agonist support demonstrated a significantly higher pregnancy rate.

Given the studies proving the positive impact of GnRH agonist, there is a need for a prospective randomized controlled trial to evaluate the use of GnRH agonist support in frozen embryo transfers.

Aims and Significance:

This study aims to compare pregnancy rates between women receiving GnRH agonist treatment and those receiving standard progesterone-based luteal support during frozen embryo transfers in natural cycles as part of IVF treatments.

Conducting a prospective comparative study will enable us to assess the effectiveness of GnRH agonist treatment relative to standard luteal phase support. Based on the results, the investigators may consider treatment with intranasal GnRH agonist, which improves quality of life and may also enhance pregnancy and live birth rates.

Methods:

The study will be conducted on patients scheduled to undergo modified natural cycles. Participants will be randomly allocated into two groups:

1. Study Group: Luteal phase support will begin on the day of ovulation with Nafarelin nasal spray (200 mcg twice daily) for two weeks, until pregnancy blood test (hCG).
2. Control Group: Luteal phase support will be provided through vaginal progesterone. Endometrin 100 mg twice daily. If the hCG test is positive, the supportive treatment will continue until the 8th week of pregnancy, as per the attending physician's instructions.

Clinical follow-up will include monitoring for clinical pregnancy outcomes, miscarriage rates, and live births.

Publications & conference data

No peer-reviewed publications indexed yet for this trial.