L26/P-364 Adenomyosis versus Endometriosis: Distinct Reproductive Outcomes in Infertile Women Diagnosed by Ultrasound

Abstract Study question Do adenomyosis and endometriosis diagnosed by ultrasound differently affect reproductive outcomes in infertile women when present alone or combined? Summary answer Adenomyosis is associated with longer infertility and more ART use, while isolated endometriosis shows relatively better reproductive outcomes. What is known already Endometriosis and adenomyosis are common in infertile women and are increasingly diagnosed using standardized ultrasound criteria.Both conditions are associated with reduced fertility and poorer ART outcomes, but their relative and combined impact remains unclear.Previous studies often relied on surgical diagnosis or evaluated each disease separately.Few studies have compared reproductive outcomes among women with isolated adenomyosis, isolated endometriosis, and combined disease using modern ultrasound classifications. Clarifying these differences may help tailor fertility counselling and management strategies. Study design, size, duration Observational cohort study including 160 infertile women referred to a tertiary ultrasound unit between 2020 and 2025. Participants were allocated into four equal groups (n = 40): isolated adenomyosis (A), isolated endometriosis (E), combined disease (A+E), and infertility without uterine pathology (I). Reproductive outcomes were compared across groups. Participants/materials, setting, methods Diagnoses followed MUSA and IDEA criteria. Exclusion criteria were male-factor infertility, genetic or endocrine disorders, uterine malformations, and significant fibroids. Primary outcome was live birth rate. Secondary outcomes were overall pregnancy and miscarriage rates from spontaneous conception and ART. Ultrasound features, including uterine volume and lesion distribution, were analyzed. Main results and the role of chance Infertility duration was longer in A and A+E versus I (p < 0.05), while E and I did not differ. Live birth rates were 40% (A), 35% (A+E), 30% (E), and 55% (I). Spontaneous pregnancy was more frequent in E than A (30% vs 10%, p < 0.05). Total pregnancies were higher in I than A (75% vs 50%). Most women required ART (70–80%). Mean embryo transfers were higher in A and A+E and lowest in E, without statistical significance. Compared with A, group I had higher odds of pregnancy (OR 3.0, 95% CI 1.16–7.73). Uterine volume was lower in I than other groups (p < 0.05). Lesion patterns differed between A (mainly focal/anterior) and A+E (mixed/posterior) (p < 0.05). Limitations, reasons for caution Single-center design and relatively small sample size may limit generalizability. Wider implications of the findings Ultrasound-based identification of adenomyosis and endometriosis can refine fertility prognosis. Adenomyosis appears to have a greater negative reproductive impact, supporting individualized counselling and management. Trial registration number No