Reduced Oestrogen Dosage to Improve the Outcome of Frozen-thawed Embryo Transfer

Study Overview
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Brief Summary
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This study is a single-center, randomized, controlled prospective study. Those who will recieve hormone replacement therapy-frozen thawed embryo transfer (HRT-FET) are enrolled in the study. To determine the effect of oestrogen dosage reducion on maternal and fetal complications in HRT-FET cycles while maintaining the similar clinical pregnancy outcome in HRT-FET cycles with regular oestrogen dosage.

Detailed Description
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According to the enrollment and exclusion criteria, the patients were enrolled, and the subjects were randomly divided into two groups by computer randomization. Group A was the reduced oestrogen dosage group (test group). Group B was the regular hormone replacement group (control group).

Official Title
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A Randomized Controlled Trial on Reducing Oestrogen Dosage to Improve the Clinical Outcome of Frozen-thawed Embryo Transfer

Conditions
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FET

Intervention / Treatment
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* Other: Low oestrogen dosage


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Female; Aged between 20 and 40 years old; Frozen thawed embryo transfer is proposed, and the type of transferred embryo is blastocyst (the number of transferred embryos is 1); Body mass index (BMI) ≤ 28 kg/m2, ≥ 18.5 kg/m2; The total number of transfer cycles was < 3; Volunteer to participate in the study and sign the informed consent. Exclusion Criteria: Patients with chromosomal abnormalities; Contraindications to hormone replacement therapy; Patients with uterine myoma, severe adenomyosis, endometriosis, congenital uterine malformation, endometrial tuberculosis, intrauterine adhesions and other diseases that significantly affect embryo implantation; Participating in other clinical studies.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Low oestrogen<br>The patients take orally estradiol tablets 2 mg (Femoston) q.d. during the HRT-FET cycles | Other: Low oestrogen dosage<br>* From the second day of the menstrual cycle, femoston (estradiol tablets) were orally taken 2 mg q.d.. The endometrial thickness and serum oestrogen and progesterone levels were monitored on the 12th to 14th days of the menstrual cycle.<br>|
| No Intervention: Regular oestrogen<br>The patients take orally estradiol tablets 2 mg (Femoston) t.i.d. during the HRT-FET cycles | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Clinical pregnancy rate | Clinical pregnancy is defined as the presence of gestational sac observed by ultrasound. The proportion of clinical pregnancy cycles to total FET cycles is the clinical pregnancy rate. | 45 days after embryo transfer | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Embryo implantation rate | The proportion of the number of implanted embryos to the total number of transferred embryos is the embryo implantation rate. | 45 days after embryo transfer | 
| Early pregnancy loss rate | The early pregnancy loss rate refers to the proportion of patients with pregnancy loss before 12 weeks of gestation in the total clinical pregnancy patients. | 12 weeks after embryo transfer | 
| Incidence of thrombosis | Thrombosis incidence refers to the proportion of patients with deep venous thrombosis in the total patients. | 12 weeks after embryo transfer | 
| Incidence rate of gestational hypertension | The incidence rate of gestational hypertension refers to the proportion of patients with gestational hypertension in the total pregnant patients. | 45 weeks after embryo transfer | 
| Premature birth rate | Preterm birth rate refers to the proportion of patients with preterm birth in all pregnancies. | 41 weeks after embryo transfer | 
| Proportion of low birth weight infants | The proportion of low birth weight infants refers to the proportion of low birth weight infants in all newborns. | 41 weeks after embryo transfer |