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The Journal of Obstetrics and Gynecology of India

Published in:

12-08-2023 | Infertility | Original Article

Improved Pregnancy Outcomes and Endometrial Receptivity by Thawed Frozen Embryo Transfer in Mildly Stimulated Cycles with Letrozole Combined with Estrogen in Women with Unresponsive Thin Endometrium Compared to Standard Endometrial Preparation with Estrogen Alone: A Retrospective Study

Authors: Narayana Nagaraja, S. D. Poddar, Seema Rai, Vishesh Verma, Kumar Abhisheka, Abha Khurana

Published in: The Journal of Obstetrics and Gynecology of India | Issue 4/2023

Abstract

Context

Infertile women undergoing frozen embryo transfer (FET) cycles may not show optimal endometrial growth with estrogens alone.

Aim

To evaluate clinical effect of mild stimulation with letrozole and estrogens on endometrial growth in comparison to standard endometrial preparation with oral and topical estrogens in infertile women with unresponsive thin endometrium undergoing FET.

Settings and design

Retrospective observational case–control study.

Material and methods

Forty women unresponsive to first AC-FET cycle were given mild stimulation with letrozole and estrogens as second LE-FET cycle for endometrial preparation (LE-FET study group) and compared with 40 historical controls who had received two cycles of AC-FET (AC-FET control group). Responses were assessed by optimal endometrial thickness (≥ 7 mm) and clinical pregnancy.

Statistical analysis

Descriptive statistics were elaborated by mean ± SD and percentages. Results were expressed by mean ± SD, unpaired t test for difference in endometrial thickness, chi square and Fisher exact test to compare the difference in pregnancy among both groups.

Results

Mean endometrial thickness was significantly increased in LE-FET study group (6.68 ± 2.09 mm) versus AC-FET control group (5.35 ± 1.90 mm). Higher clinical pregnancy rate was noted in study group as compared to control group (35% versus 12.5%).

Conclusion

This study suggests that letrozole with estradiol (LE-FET) compared to estradiol alone (AC-FET) for second cycle significantly increased endometrial thickness and improved clinical pregnancy rates in women with unresponsive thin endometrium after first AC-FET cycle with estradiol alone. Addition of letrozole to estrogen upfront for FET cycles may enhance endometrial receptivity and might improve pregnancy outcomes.

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Title: Improved Pregnancy Outcomes and Endometrial Receptivity by Thawed Frozen Embryo Transfer in Mildly Stimulated Cycles with Letrozole Combined with Estrogen in Women with Unresponsive Thin Endometrium Compared to Standard Endometrial Preparation with Estrogen Alone: A Retrospective Study
Authors: Narayana Nagaraja
S. D. Poddar
Seema Rai
Vishesh Verma
Kumar Abhisheka
Abha Khurana
Publication date: 12-08-2023
Publisher: Springer India
Keywords: Infertility
Infertility
Letrozole
Estrogens
Estradiol
Published in: The Journal of Obstetrics and Gynecology of India / Issue 4/2023
Print ISSN: 0971-9202
Electronic ISSN: 0975-6434
DOI: https://doi.org/10.1007/s13224-023-01813-4

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Improved Pregnancy Outcomes and Endometrial Receptivity by Thawed Frozen Embryo Transfer in Mildly Stimulated Cycles with Letrozole Combined with Estrogen in Women with Unresponsive Thin Endometrium Compared to Standard Endometrial Preparation with Estrogen Alone: A Retrospective Study

Abstract

Context

Aim

Settings and design

Material and methods

Statistical analysis

Results

Conclusion

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

Context

Aim

Settings and design

Material and methods

Statistical analysis

Results

Conclusion

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