A Randomized Trial Comparing the Live Birth Rate of Immediate Versus Delayed FET Following a Freeze-all Strategy

Not Applicable

Recruiting

• Conditions: IVF; Frozen Embryo Transfer
• Interventions: Procedure: Immediate FET; Procedure: Delayed FET

• Registration Number: NCT04371783
• Lead Sponsor: ShangHai Ji Ai Genetics & IVF Institute

Brief Summary

This randomized trial we aim to compare the live birth rate of immediate versus delayed FET replacing a single blastocyst in the first FET of the first stimulated IVF cycle following. The hypothesis is that the live birth rate of the immediate FET is higher than the delayed FET replacing a single blastocyst in the first FET of the first stimulated IVF cycle following a freeze-all strategy. Women will undergo IVF/ICSI in the centre as clinically indicated. Standard ovarian stimulation with gonadotrophins in a Gonadotrophin releasing hormone (GnRH) antagonist protocol will be employed. Hormone replacement treatment (HRT) will be used in subsequent FET cycles. On Day 3 of the menstrual cycle, we will measure the anxiety levels using the Chinese State-Trait Anxiety Inventory and serum E2, cortisol levels will be checked on the same day.

Recruited women having the first FET cycle following a freeze all strategy will be randomly assigned on the day of blastocyst(s) freezing according to a computer-generated randomization list into one of the following two groups.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2020-04-29
• Study First Submitted QC: 2020-04-29
• Study First Posted: 2020-05-01
• Study Start: 2020-05-04
• Status Verified: 2024-02
• Last Update Submitted: 2024-03-09
• Last Update Posted: 2024-03-13
• Primary Completion: 2025-12-31
• Study Completion: 2026-06-30

Recruitment & Eligibility

• Status: RECRUITING
• Sex: Female
• Target Recruitment: 828

Inclusion Criteria

1. Women aged 20-40 years at the time of IVF/ICSI
2. Women undergoing their first FET of the first IVF cycle following a freeze-all strategy
3. Undergoing IVF with GnRH antagonist
4. At least one frozen blastocyst

Exclusion Criteria

1. Severe ovarian hyperstimulation syndrome during the first IVF/ICSI cycle
2. Preimplantation genetic testing
3. Use of donor oocytes
4. Presence of untreated hydrosalpinx or endometrial polyp on scanning during ovarian stimulation

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Immediate FET group	Immediate FET	FET will be performed in the first menstrual cycle following the stimulated IVF cycle
Delayed FET group	Delayed FET	FET will be performed in the second menstrual cycle following the stimulated IVF cycle

Primary Outcome Measures

Name	Time	Method
live birth	1 year after FET	deliveries ≥22 weeks gestation with heartbeat and breath

Secondary Outcome Measures

Name	Time	Method
implantation rate	6 weeks' gestation	the number of gestational sacs per blastocyst transferred
ectopic pregnancy	ectopic pregnancy during 12 weeks gestation	pregnancy outside the uterine cavity
ongoing pregnancy	12 weeks' gestation	a viable pregnancy beyond 12 weeks' gestation
positive hCG	2 weeks after FET	serum β-hCG ≥10 mIU/mL
clinical pregnancy	6 weeks' gestation	presence of intrauterine gestational sac by trans-vaginal ultrasound at 6 gestational weeks.
miscarriage	1 year after FET	a clinically recognized pregnancy loss before the 22 weeks of pregnancy
multiple pregnancy	multiple pregnancy beyond gestation 12 weeks	more than one intrauterine sacs on scanning
birthweight of newborns	1 year after FET	the birth weight of newborns

Trial Locations

Locations (1)

Shanghai JiAi Genetics & IVF Institute; 🇨🇳 Shanghai, Shanghai, China