Related Experiment Video
Updated: Jul 13, 2026

Fertility Preservation Through Oocyte Vitrification: Clinical and Laboratory Perspectives
Published on: September 16, 2021
Luteal phase oestradiol administration in ovarian stimulation cycles with GnRH antagonist is comparable to the GnRH
J S Cunha Filho1, L F Terres, F Holanda
1Ob/Gyn depto., Hospital de Clínicas de Porto Alegre, Programa de Pós-graduação em Ciências Médicas, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcellos, 2350, Porto Alegre, RS, CEP 90035-003, Brazil. sabino@via-rs.net
Purpose:
The purpose of the study was to compare the effectiveness of GnRH antagonist with luteal phase estradiol administration to GnRH agonist cycles, long protocol.
Methods:
55 IVF-ICSI patients received oestradiol in the luteal phase of the cycle, before a cycle with GnRH antagonist. Fifty-five patients submitted to IVF-ICSI with the use of agonist were allocated, age matched, as a control group (historical control). The primary outcome was the number of retrieved oocytes.
Results:
Patients were similar in terms of clinical characteristics. No differences were found in the number of oocytes retrieved (study group, 8.1 +/- 4.7; control group, 7.4 +/- 4.5) or in oocyte quality.
Conclusions:
We clearly demonstrated that the effectiveness of GnRH antagonist when combined with luteal phase estradiol is comparable to GnRH agonist cycles.
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