Natural Versus Artificial Cycle for Frozen-Thawed Embryo Transfer (NAFT)

Universitaire Ziekenhuizen KU Leuven

Status and phase: Completed; Phase 4

Conditions: Embryo Transfer

Treatments: Drug: Natural cycle; Drug: Micronized progesterone; Drug: Estradiol Valerate

Study type: Interventional

Funder types: Other

Identifiers

NCT03642665

S61372

Details and patient eligibility

About

This study evaluates clinical pregnancy rates, obstetrical outcome parameters, costs and patient preferences in natural cycle versus artificial cycle frozen embryo transfers (FET).

Full description

Transfer of cryopreserved embryos can be performed in a natural cycle (NC-FET) or in an artificially prepared cycle (AC-FET). Both cycle regimens have their advantages and disadvantages. So far, most comparative studies have failed to identify the optimal protocol for FET. In this study patients undergoing FET will be randomized between an endometrial preparation by a natural cycle or by an artificial cycle (by oestradiol validate and micronized progesterone).

Enrollment: 554 patients

Sex: Female

Ages: 18 to 45 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Women undergoing FET after a first, second or third fresh IVF/ICSI cycle
• Single embryo transfer (SET) or Double embryo transfer (DET)
• Female age between 18-45 year
• Women having a natural ovulatory cycle (24-35 days)
• Normal uterine cavity (fundal indentation at the cavity <10mm)
• Written informed consent

Exclusion criteria

• Use of donor gametes
• BMI > or equal to 35 kg / m2
• Any contra-indication to estrogen or progesterone supplementation (e.g. history of thrombosis, prior or current hormone-sensitive malignancy...)

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

---

554 participants in 2 patient groups

Natural cycle

Experimental group

Description:

no medication

Treatment:

Drug: Natural cycle

Artificial cycle

Active Comparator group

Description:

Oestradiol valerate (Progynova, Bayer, Germany) 6mg daily will be given from day 2 of the cycle. The dose of Progynova is increased to 8mg daily if the endometrial thickness is less than 7mm after 7-10 days of Progynova use. Progynova will be discontinued the day of the pregnancy test in case of a negative result. In case of a pregnancy, Progynova will be continued until 12 weeks or until diagnosis of a non-viable pregnancy. Micronized progesterone (Utrogestan, Besins, Belgium) 200 mg vaginally three times daily is started as soon as the endometrial thickness is 7 mm. Utrogestan will be discontinued the day of the pregnancy test in case of a negative result. In case of a pregnancy, Utrogestan will be continued until 12 weeks or until diagnosis of a non-viable pregnancy.

Treatment:

Drug: Estradiol Valerate

Drug: Micronized progesterone