Progesterone-modified Natural Cycle for FET (COMPROSET)

Shandong University of Traditional Chinese Medicine

Status and phase: Not yet enrolling; Phase 3

Conditions: Infertility, Female

Treatments: Drug: Progesterone-modified natural cycle preparation for frozen embryo transfer; Drug: Hormone replacement therapy cycle preparation for frozen embryo transfer

Study type: Interventional

Funder types: Other

Identifiers

NCT06644794

P4mNC@SDUTCM

Details and patient eligibility

About

Hormone replacement therapy (HRT) cycles, despite the ease of synchronizing embryo thawing and embryo transfer timing, increase the risk of pregnancies and obstetric complications compared to natural cycles (NC). By ensuring the presence of the corpus luteum while reducing the number of monitoring sessions, the progesterone modified natural cycle (P4mNC) offers more convenience for the patient than the normal NC. This study is designed to compare the effects of P4mNC and HRT cycles on FET outcomes.

Enrollment: 336 estimated patients

Sex: Female

Ages: 21 to 44 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Patients aged 21 to 44 years undergoing FBT
• Body mass index (BMI) 18-35 kg/m2
• Having regular ovulatory cycles

Exclusion criteria

• Untreated uterine adhesions
• Medical contraindications to estrogen and progesterone therapy
• Illnesses contraindicating assisted reproductive technology or pregnancy
• History of recurrent implantation failures (> 2 embryo transfer failures)

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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336 participants in 2 patient groups

P4mNC group

Experimental group

Description:

On days 8-12 of the menstrual cycle (MC), depending on the length of the patient's MC, transvaginal ultrasound is used to monitor follicular development and endometrial growth. Vaginal micronized progesterone (Utrogestan, Besins, Belgium) is started at 200 mg in the afternoon and 200 mg in the evening when the dominant follicle reached ≥16 mm and the endometrial thickness is at least 7 mm. A blastocyst is transferred on day 5 after the addition of progesterone. On day 14 after blastocyst transfer, serum β-hCG levels are measured. Upon positive serum pregnancy testing, progesterone support will continue until 8-10 weeks of gestation. However, afternoon progesterone use is eliminated for 30 days after embryo transfer.

Treatment:

Drug: Progesterone-modified natural cycle preparation for frozen embryo transfer

HRT group

Active Comparator group

Description:

Endometrial preparation will begin on the second day of the menstrual cycle with oral estradiol (E2) valerate at a dose of 2 mg twice daily. When the patient's endometrial thickness is ≥7 mm, vaginal progesterone administration will be initiated at a dose of 200 mg 3 times daily. On day 5 of the progesterone administration, blastocysts are thawed and transferred. For patients with endometrial thickness \<7 mm, patients continued oral E2 until the endometrium is ≥7 mm. On day 14 after blastocyst transfer, serum β-hCG levels are measured. Upon positive serum pregnancy testing, E2 and progesterone supplementation is continued for 8-10 weeks of gestation.

Treatment:

Drug: Hormone replacement therapy cycle preparation for frozen embryo transfer