Immediate Versus Postponed Freeze-all Embryo Transfer in Hyperresponders
- Conditions
- IVF
- Interventions
- Biological: the timing of embryo transfer in freeze-all cycles
- Registration Number
- NCT05483270
- Lead Sponsor
- Peking University Third Hospital
- Brief Summary
This is a multicenter, randomised controlled trial. The investigators plan to randomise 836 participants to the immediate FET or the postponed FET from the day of oocyte retrieval to the last day of that menstrual cycle in a 1:1 rate. Primary outcome will be the live birth rate after the embryo transfer.
- Detailed Description
It is postulated that postponing embryo transfer for at least one menstrual cycle after a freeze-all cycle can minimise the possible residual negative effect caused by ovarian stimulation and can promote the resumption of a normal ovulatory cycle and the receptivity of endometrium. Nevertheless, emerging evidence suggests a higher live birth rate in the immediate freeze-all embryo transfer (FET) cycles compared to that in the delayed group. It is unclear the whether postponed FET is superior in hyperresponders. The investigators hypothesize the success rate in the postponed FET for at least one menstrual cycle after oocyte retrieval is higher than in the immediate FET in hyperresponders.
Objective: To evaluate whether the postponed FET for at least one menstrual cycle after oocyte retrieval is superior to the immediate FET in the first menstrual cycle after oocyte retrieval in hyperresponders in terms of live birth rates.
Design: a multicenter, randomised controlled trial Patients: The investigators plan to randomise participants to the immediate FET and the postponed FET from the day of oocyte retrieval to the last day of that menstrual cycle.
Primary outcome: live birth rate after the embryo transfer. Patients who get pregnant will be followed up until 6 weeks after delivery.
Sample size: The investigators plan to enroll 836 participants in a 1:1 rate.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- Female
- Target Recruitment
- 845
- Women aged 20 to 42 years old;
- Written informed consent;
- Women scheduled for freeze-all embryo transfer;
- Women with the number of oocyte collected higher than 15.
- Women with a history of at lease three failed transfer cycles;
- Women with an endometrial thickness less than 7 mm on the triggering day;
- Severe uterine malformations.
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Immediate FET group the timing of embryo transfer in freeze-all cycles Freeze-all embryo transfer will be carried out in the menstrual cycle immediately following oocyte retrieval. Postponed FET group the timing of embryo transfer in freeze-all cycles Freeze-all embryo transfer will be carried out during the second menstrual cycle to 6 months after oocyte retrieval.
- Primary Outcome Measures
Name Time Method Live birth after the first embryo transfer At least 22 months gestation after the first embryo transfer cycle Live birth is defined as the delivery of at least one baby after 22 weeks of gestation that exhibits any sign of life.
- Secondary Outcome Measures
Name Time Method Biochemical pregnancy about 12 days after embryo transfer defined as a positive pregnancy test
Miscarriage 6-22 weeks of gestation defined as spontaneous loss of a clinical pregnancy before 22 completed weeks of gestational age, in which the embryo(s) or fetus(es) is/are nonviable or is/are absorbed or expelled from the uterus.
Gestational diabetes mellitus after 24 weeks of gestation defined as carbohydrate intolerance of variable severity with onset or first recognition during pregnancy as determined from the diagnosis in the obstetrical medical record
Stillbirth the day of delivery defined as the absence of signs of life at or after birth
Ectopic pregnancy about 6 weeks after embryo transfer defined as embryo implanted at any site other than the endometrial lining of the uterus cavity
Gestational hypertension after 20 weeks of gestation defined as the development of blood pressure greater than 140/90 mmHg after pregnancy without proteinuria or other signs of preeclampsia
Mode of delivery the day of delivery Vaginal birth or Caesarean Section
Ongoing pregnancy 12 weeks' gestation or beyond after the first embryo transfer cycle defined as pregnancy with detectable heart rate at 12 weeks' gestation or beyond
Cumulative live birth 6 month after the first embryo transfer the cumulative rate of live born children conceived within six months of the first FET cycle.
Postpartum hemorrhage the day of delivery defined as the loss of 500 ml of blood or more after completion of the third stage of labor
Birth weight the day of delivery Birth weight
Clinical pregnancy around 7 weeks' gestation after the first embryo transfer cycle defined as at least one gestational sac on ultrasound at around 7 weeks' gestation with the detection of heart-beat activity
Pre-eclampsia after 20 weeks of gestation defined as the development of gestational hypertension with proteinuria (≥300 mg/24-hour urine collection or 30 mg/dL in single urine sample) of new onset after 20 weeks of gestation
Premature rupture of membrane (PROM) rate the day of delivery defined as rupture of the amniotic membranes before the onset of labor including PROM at term and preterm PROM
Preterm delivery less than 37 and more than 21 weeks' gestational age defined as delivery of a fetus at less than 37 weeks' gestational age
Placenta previa the day of delivery defined as a placenta that is implanted over or very close to the internal cervical orifice
Trial Locations
- Locations (1)
Peking university third hospital
🇨🇳Beijing, China