P-277 Focal rather than diffuse nature of adenomyosis might be more detrimental to IVF outcomes after single euploid embryo transfer
Authors: Trinchant R , Cruz M , Requena A 
Published: July 2024

Abstract

Study question
Is the nature of adenomyosis a factor to consider after a single euploid embryo transfer?

Summary answer
Focal adenomyosis was associated with lower live birth rate per transfer when compared to diffuse adenomyosis.

What is known already
Adenomyosis is widely described to hamper reproductive potential of women who suffer it. This uterine pathology has a detrimental impact on in vitro fertilization (IVF) clinical outcomes, as described by a series of recent metanalysis. Nevertheless, there is scarce evidence regarding clinical studies that address the impact of adenomyosis depending either on its diffuse or focal nature.

Study design, size, duration
A multicenter retrospective cohort study in which 229 patients undergoing IVF treatment were included. Patients with single embryo transfer (SET) in blastocyst stage after pregestational testing for aneuploidy (PGT-A) between years 2015 and May 2023 were divided into two groups: diffuse adenomyosis (n = 167) and focal adenomyosis (n = 62).

Participants/materials, setting, methods
Inclusion criteria consisted of patients in a PGT-A program who had a cryotransfer of a single euploid blastocyst-stage embryo. Patients were diagnosed within our facilities using transvaginal ultrasonography (TVUS) prior to their IVF cycle. Diffuse adenomyosis was diagnosed when irregular endometrial-myometrial junction, increased uterine volume, ill-defined myometrial heterogeneity, presence of anechoic round myometrial cysts, hyperechoic islands, fan-shaped shadows and/or echogenic subendometrial lines were detected. Focal adenomyosis was diagnosed when foci with adenomyotic characteristics were observed.

Main results and the role of chance
Clinical pregnancy rate per embryo transfer was 81/167 (48.5%) in those women diagnosed with diffuse adenomyosis versus 23/62 (37.1%) in the focal adenomyosis group (OR = 0.63 95% CI [0.33-1.18], NS). Differences found in clinical miscarriage rate were not statistically significant, being 33/81 (40.7%) for diffuse adenomyosis and 14/23 (60.1%) for the focal adenomyosis group (OR = 2.24 95% CI [0.79-6.63], NS). A lower live birth rate per euploid embryo transfer was observed in women diagnosed with focal adenomyosis, being 9/62 (14.5%) and 48/167 (28.7%) for women who presented diffuse adenomyosis (OR = 0.42 95% CI [0.17-0.95], p=0.027). There were no statistically significant differences between childbirth delivery method (vaginal versus caesarean section). Furthermore, means of gestational age at the time of delivery, newborn size and weight and incidences of low birth weight did not differ between the two groups.

Limitations, reasons for caution
The retrospective nature of this observational study implies that possible confounders cannot be completely excluded. Also, the accurate diagnostic of adenomyosis is not without complexity and although gynecologists were equally trained to identify direct and indirect markers, different criteria may have been used

Wider implications of the findings
To our knowledge this is the first study to use an euploid model to assess the impact of the focal versus diffuse nature of adenomyosis in IVF patients. This model permits to correct for numerous covariables attributed to patient’s age and embryo genetic constitution.

Trial registration number
Not applicable