Breast ultrasound screening in young adult women undergoing infertility treatment at an infertility clinic: a retrospective observational study

BACKGROUND: Young adult women are increasingly undergoing infertility treatment; however, evidence regarding breast cancer screening in this population remains limited. Given that most women in this age group have dense breast tissue, for which mammography has limited sensitivity, breast ultrasound (US) is often used as a screening modality. A diagnosis of breast cancer during infertility treatment may affect both oncologic management and reproductive planning. This study aimed to examine the clinical relevance of breast US in women in their 30s undergoing infertility treatment at an infertility clinic. METHODS: We retrospectively analyzed 1,336 women aged 30-39 years who underwent screening breast US between November 1, 2018, and June 30, 2025. Analyses were performed on a per-woman basis, including only the first screening examination for each participant. Breast composition was categorized according to the BI-RADS 5th edition Atlas. Screening outcomes-including recall rate, positive predictive value (PPV), cancer detection rate, and US findings (mass and non-mass findings)-were assessed using medical records. The continuation of infertility treatment, defined as ongoing or resumed treatment during the diagnostic evaluation period, was descriptively evaluated as part of the clinical context. RESULTS: Of the 1,336 women, 1,277 (95.6%) were classified as having dense breasts. A total of 140 (10.5%) women were recalled for further evaluation. In these recalled cases, 147 findings were identified, comprising 113 mass lesions (76.8%) and 34 non-mass findings (23.1%). Four breast cancers were identified, corresponding to a cancer detection rate of 0.30% and a PPV of 2.86%. Histological diagnoses included one mucinous carcinoma, two invasive carcinomas of no special type (NST), and one ductal carcinoma in situ (DCIS). Following diagnostic evaluation, 124 recalled women (88.6%) continued infertility treatment. CONCLUSIONS: Breast US screening in women in their 30s undergoing infertility treatment provides descriptive findings within a specific clinical setting. The observed cancer detection rate appears to be within the range reported in previous studies; however, direct comparisons are limited due to differences in study populations and clinical contexts. The clinical course following recall was described as part of the screening pathway. Further prospective and multicenter studies are required to clarify the clinical significance of breast US screening in this population.