P-632 Characterization of body composition by dual energy x-ray absorptiometry (DXA) of infertile women with history of repeated implantation failure
Authors: Fabozzi G , Gualtieri P , Frank G , Raffaelli G , La Placa G , Cimadomo D , Klinger F  G , Soscia D  M , Argento C , Colamaria S , Giuliani M , Ferrero S , Vaiarelli A , Gennarelli G , Di Renzo L 
Published: July 2024

Abstract

Study question
Does body composition differ between fertile and infertile patients with history of repeated implantation failure (RIF)? A pilot study.

Summary answer
Compared to fertile, infertile women with history of RIF show differences in tissue distribution and bone mineralization (BM).

What is known already
It is known that being under/overweight or obese increases the risk of RIF or miscarriage probably due to the key role that adipose tissue exerts in reproduction. Body mass index (BMI) is the most used metric to define anthropometric characteristics; however, it represents a poor indicator of body composition leading to the risk of miscalculating the percentage of fat mass (FM) and underestimating the risk of reproductive failure. This study aims to analyze body composition of infertile patients by DXA, the gold standard for FM calculation and location, providing a 3-dimensional picture of body organ densities.

Study design, size, duration
This observational pilot study was conducted over 11 months. Sixty-six women were recruited and underwent all assessments.

Participants/materials, setting, methods
Out of 66 enrolled women, 16 were RIF (according to ESHRE 2023 criteria; here defined infertile women [IW] and aged 38.88±4.62 years), and 50 were women who already had at least one live birth (here defined fertile [FW] and aged 31.74±6.36 years), with varying weight ranges and BMI. The patients underwent an assessment of body composition by DXA Primus, X-ray densitometer; software v1.2.2, Osteosys Co., Ltd. Statistical analysis was conducted using IBM SPSS v21.0.

Main results and the role of chance
From FM percentage (FM%) analysis, 50% of the IW were normal-weight (NW - BMI 18.5-25, FM%&lt;30), 31.25% were NW-obese (NWO - BMI 18.5-25, FM%≥30), and 18.75% were Obese (BMI≥25, FM%≥30). Of the FW, 48% were NW, 32% NWO, and 20% obese.
Based on the Shapiro-Wilk normality test, independent samples t-test analysis or Wilcoxon’s nonparametric tests were adopted. Differences in body composition emerged between the IW and FW groups.
IW showed a significant increase in right leg lean (7.38±1.03 vs 6.77±1.13, p &lt; 0.05) and in left total tissue (28.02±5.3 vs 18.94±9.19, p &lt; 0.0001) compared with FW. In contrast, FW showed a significant increase in left trunk tissue (22.85±8.33 vs 14.17±7.03, p &lt; 0.0001), and in left and right trunk BM (367.6±90.47 vs 306.66±69.67, p &lt; 0.005 and 368.35±94.49 vs 313.73±76.98, p &lt; 0.012) versus IW.

Limitations, reasons for caution
Given the pilot nature of the study, its small sample size may influence the outcomes.
Moreover, individual variations beyond dietary factors could contribute to the difference, including age.
Additionally, our findings should be confirmed in a broader population.

Wider implications of the findings
The significant differences observed in IW compared to FW regarding body composition, especially concerning the tissue distribution and BM, encourage further investigations, particularly exploring possible hormonal, metabolic, and genetic correlations, to better understand the distinctive characteristics of this group.

Trial registration number
ClinicalTrials.gov NCT01890070.