Endometrial Preparation in Frozen Embryo Transfer Cycles
- Conditions
- IVF
- Interventions
- Registration Number
- NCT06181305
- Lead Sponsor
- Rahem Fertility Center
- Brief Summary
In order to get optimal pregnancy rates after frozen embryo transfer (FET), the embryo stage and endometrium should be synchronized. Endometrial preparation is done by either natural, artificial (Hormonal replacement therapy HRT) , modified natural methods or mild ovarian stimulation. HRT cycle has a better schedualization however, there are some reports about higher rates of miscarriage, pregnancy induced hypertension (PIH) and preeclampsia (PET) in HRT cycles. A recent study has found that incorporation of the aromatase inhibitor (letrozole) to HRT cycles was associated with better FET outcomes in comparison to hormonal replacement therapy cycles alone. Meanwhile, mild ovarian stimulation protocol can be done either by oral drugs like letrozole or by letrozole plus gonadotropins . So this study aims to compare the reproductive outcomes in two endometrial preparation protocols for frozen embryo transfer cycles; letrozole mild ovarian stimulation versus HRT plus letrozole incorporation.
- Detailed Description
In order to get optimal pregnancy rates after frozen embryo transfer (FET), the embryo stage and endometrium should be synchronized. This can be done by hormonal replacement therapy (HRT), natural cycles (NC), modified natural cycles or mild ovarian stimulation. In hormonal replacement therapy cycle, estrogen and progesterone are sequentially given to resemble the hormonal course of the natural cycle . Hormonal replacement therapy cycle has a better schedualization and is used for patients with irregular cycles as polycystic ovary syndrome ( PCOS). However, there are some reports about higher rates of miscarriage, pregnancy induced hypertension (PIH) and preeclampsia (PET) in HRT cycles.
A recent study has found that incorporation of the aromatase inhibitor (letrozole) to HRT cycles was associated with better FET outcomes in comparison to HRT cycles alone. Ongoing pregnancy rate (OPR) was higher in HRT plus letrozole group than HRT only group.
Letrozole is a third-generation aromatase inhibitor that leads to mono-ovulatory cycles with short half-life . Miller and his colleagues found that letrozole increased Integrin expression and improved pregnancy and implantation rates among women with endometrial receptivity defects . Another study found that ovarian stimulation with letrozole was associated with increase in the expression of uterine receptivity markers including integrin, leukemia inhibitory factor, and L-selectin.
Recruitment & Eligibility
- Status
- RECRUITING
- Sex
- Female
- Target Recruitment
- 210
- Women aged between 18 and 37 years with either regular cycles or oligomenorrhoea or amenorrhoea.
- Women undergoing FET cycles.
- Participants should have at least one good-quality blastocyst available for vitrification and also for transfer after warming.
- Participants having optimal endometrium before starting luteal phase support
- Women who will refuse to participate in in the study.
- Women who will not reach the optimal endometrium.
- Participants that don't have at least one good-quality blastocyst for transfer after warming.
- PGT embryos will be excluded.
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Group A (HRT plus letrozole incorporation) estradiol valerate and letrozole Exogenous oestradiol in the form of 2 mg oral oestradiol valerate , three times daily will be started on the 2nd or 3rd day of the cycle. Tri-laminar endometrium of ≥ 9 mm will be the targeted cut-off. If the endometrium does not yet reach the target, oestradiol supplementation will be continued with serial US assessment until the targeted cut-off will be reached. Upon reaching the target endometrium, oral letrozole tablets 2.5 mg will be started twice daily for 5 days only with continuation of 6 mg daily oestradiol supplementation. Then, daily intramuscular progesterone in oil (100 mg intramuscular progesterone) will be started once per day with continuation of 6 mg oestradiol interventions: Drug:estradiol valertae Drug :letrozole 2.5 mg tablet Group B (Letrozole mild ovarian stimulation) letrozole 2,5 mg tablet Oral letrozole 2.5-5 mg daily on cycle day(3-7) will be added . TVS will be performed from cycle day 8-10 to make sure that a dominant follicle has been recruited with the endometrium thickness ≥ 7 mm . Upon reaching the dominant follicle (18-20mm) , endometrial thickness will be measured on the day of ovulation trigger and blood sample will be withdrawn from each patient for assessment of E2 , P4 and LH levels. Patients with low LH level , high E2 level , low P4 level (\<1 ng/ml) will continue in the RCT; 10,000unit HCG will be injected as ovulation trigger intervention : Drug :letrozole 2.5mg tablet procedure: on the day of ovulation trigger blood sample will be withdrawn from each patient for assessment of E2 , P4 and LH levels.
- Primary Outcome Measures
Name Time Method ongoing pregnancy rate (OPR) 12 weeks Number of pregnant women with viable fetus at 12 weeks gestation per woman randomized
- Secondary Outcome Measures
Name Time Method Clinical pregnancy rate (CPR) 5 weeks after embryo transfer Number of gestational sacs with evident fetal pulsations per woman randomized,ectopic pregnancy is also includded pregnancy is aslo included
Implantation rate 21 days after embryo transfer Number of gestational sac recognized by ultrasound in uterus 3 weeks after embryo transfer
Ectopic pregnancy 7 week pregnancy outside the uterine cavity diagnosed by ultrasound ,surgical visualization or histopathology
Miscarriage rate 12 weeks Number of miscarriages per woman with positive pregnancy tests
Number of participants with Hypertensive disorders of pregnancy 20 weeks gestation till postpartum gestational hypertension or preeclampsia
Number of participants with Large for gestational age from gestation till delivery A birth weight greater than the 90th centile of the sex-specific birth weight for a given gestational age reference
live birth rate 22 completed weeks of gestational age The complete expulsion or extraction from a woman of a product of fertilization,after 22 complete weeks of gestational age;which,after such separation,breathes or shows any other evidence of life,such as heart beat,umblical cord pulsation or definite movement of voluntary muscles,irrespective of whether the umblical cord has been cut or the placenta is attached.A birth weight of 500 grams or more can be used if gestational age is unknown.Live births refer to the individual newborn ;for example,a twin delivery represents two live births
Trial Locations
- Locations (1)
Rahem fertility center
🇪🇬Zagazig, Egypt