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Letrozole for Frozen Embryo Transfer (FET) in Patients With Polycystic Ovary Syndrome (PCOS) (LEFT)

C

CRG UZ Brussel

Status and phase

Withdrawn
Phase 4

Conditions

IVF
Polycystic Ovary Syndrome
Ovulation Disorder
Infertility, Female

Treatments

Drug: Letrozole
Drug: estradiol valerate

Study type

Interventional

Funder types

Other

Identifiers

NCT04002635
2019LEFT001

Details and patient eligibility

About

To offer patients with oligomenorrhoea or amenorrhoea an alternative to frozen embryo transfer in an artificial cycle, endometrial preparation using letrozole may be a valuable option. Letrozole, a potent, reversible nonsteroidal aromatase inhibitor with relatively short half-life, can successfully induce ovulation without any adverse anti-estrogenic effects and thus without affecting the endometrium. The use of letrozole typically results in monofollicular growth and this reduces the effect of supraphysiological levels of estrogen on the endometrium and embryo. The purpose of this study is to compare a frozen-thawed embryo transfer in an artificial cycle with a letrozole-induced ovulatory cycle, specifically in PCOS patients. The primary outcome is early pregnancy loss.

Sex

Female

Ages

18 to 40 years old

Volunteers

Accepts Healthy Volunteers

Inclusion criteria

  • Age more than or equal to 18 and less than or equal to 40
  • BMI more than or equal to 18 and less than or equal to 35
  • Diagnosis of PCOS according to Rotterdam criteria
  • Normal gynaecological ultrasound < 6 months before inclusion
  • Signed informed consent form
  • Day 5 or 6 frozen-thawed embryo transfer, blastocyst stage

Exclusion criteria

  • Recurrent implantation failure
  • Recurrent miscarriage
  • Presence of adenomyosis
  • Untreated intrauterine pathology
  • rAFS (revised American Fertility Society) Grade III or IV endometriosis
  • Hydrosalpinx
  • In vitro maturation (IVM)
  • Untreated autoimmune disorders
  • (History of) malignancy
  • Allergy or reaction to the use of progynova, utrogestan and/or letrozole in the past
  • Pre-implantation genetic testing (PGT)

Trial design

Primary purpose

Treatment

Allocation

Randomized

Interventional model

Parallel Assignment

Masking

None (Open label)

0 participants in 2 patient groups

Hormonal Replacement Therapy
Active Comparator group
Description:
Artificial preparation of the endometrium using estradiol valerate 2mg 3x/day, and vaginal micronized progesterone 2x 400mg/day.
Treatment:
Drug: estradiol valerate
Letrozole
Experimental group
Description:
Using letrozole for ovulation induction before planning the frozen embryo transfer
Treatment:
Drug: Letrozole

Trial contacts and locations

0

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Data sourced from clinicaltrials.gov

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