IVF
Conditions
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.
Interventions
BIOLOGICALthe timing of embryo transfer in freeze-all cycles
Immediate FET group Freeze-all embryo transfer will be carried out in the menstrual cycle immediately following oocyte retrieval. Postponed FET group Freeze-all embryo transfer will be carried out during the second menstrual cycle to 6 months after oocyte retrieval.
Sponsors
Women's Hospital School Of Medicine Zhejiang University
The Affiliated Hospital Of Guizhou Medical University
Shengjing Hospital
Peking University Third Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
FEMALE
Age
20 Years to 42 Years
Healthy volunteers
Yes
Inclusion criteria
* 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.
Exclusion criteria
* 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.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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
| Measure | Time frame | Description |
|---|---|---|
| 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 |
| Biochemical pregnancy | about 12 days after embryo transfer | defined as a positive pregnancy test |
| Ectopic pregnancy | about 6 weeks after embryo transfer | defined as embryo implanted at any site other than the endometrial lining of the uterus cavity |
| 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. |
| 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. |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| Stillbirth | the day of delivery | defined as the absence of signs of life at or after birth |
| Mode of delivery | the day of delivery | Vaginal birth or Caesarean Section |
| 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 |
Countries
China
Outcome results
None listed