O-270 Does the ‘freeze all' strategy improve the chances of birth in the presence of adenomyosis?
Authors: Bourdon M , Fouque Gadol L , Maignien C , Bordonne C , Chargui A , Marcellin L , Maitrot Mantelet L , Charles C , Santulli P 
Published: June 2023

Abstract

Study question
Does the freeze all strategy improve cumulative live birth rates in infertile women affected with adenomyosis?

Summary answer
The freeze all strategy in adenomyosis-affected women is associated with significantly higher cumulative live birth rates.

What is known already
Controlled ovarian stimulation enhances the efficacy of assisted reproductive technology (ART) by permitting multiple-oocyte yields, but also may alter endometrial receptivity by an earlier endometrial development which could in turn contribute to diminished pregnancy chances. Technical improvements in vitrification made deferred frozen-thawed embryo transfer (freeze –all strategy) a feasible alternative to fresh embryo transfer (ET). In adenomyosis, the eutopic endometrium is abnormal and its functional alterations are seen as likely to alter the quality of endometrial receptivity. One question in the adenomyosis ART-management is to know whether a freeze all strategy could lead to an increase in reproductive outcomes.

Study design, size, duration
This cohort study conducted in a tertiary care university hospital included adenomyosis-affected women undergoing blastocyst embryo transfer following in vitro fertilization / intracytoplasmic sperm injection (IVF/ICSI) between 01/01/2018 to 31/11/2021. The diagnosis of adenomyosis was based on imaging criteria (e.g. transvaginal ultrasound and/or magnetic resonance imaging).

Participants/materials, setting, methods
Women who underwent a freeze all strategy were compared to those who underwent a fresh ET strategy. Statistical analyses were conducted using univariate and multivariate logistic regression models. The primary outcome was the cumulative live birth rate (LBR).

Main results and the role of chance
A total of 306 women were included in the analysis: 111 in the fresh ET group and 195 in the freeze all group. The phenotype of adenomyosis (internal diffuse adenomyosis, external focal adenomyosis and adenomyomas) was not significantly different between the two groups. The cumulative live birth rate was significantly increased in the freeze all group compared to the fresh ET group [86 (44.1%) vs. 34 (30.6%), p = 0.020]. The cumulative OPR [89 (45.6%) versus 37 (33.3%), p = 0.035] and the cumulative CPR [122 (62.6%) vs. 53 (47.7%), p = 0.011] were significantly higher in freeze all group compared to the fresh group, whereas the early miscarriage rate was not significantly different between the two groups. After multivariate logistic regression analysis, the freeze all strategy in women with adenomyosis was associated with a significant increase in the live birth rate as compared to fresh ET (OR = 1.85; 95% CI = 1.06 – 3.24; p = 0.031).

Limitations, reasons for caution
This analysis consists in a retrospective cohort study. The inclusion of patients from a referral center specialized in the management of adenomyosis and endometriosis could constitute a selection bias, as these women may have had particularly severe forms of adenomyosis.

Wider implications of the findings
The freeze all strategy could be an attractive option to increase ART success rates, in adenomyosis-affected womenundergoing IVF/ICSI.

Trial registration number
NA