Preconception Arcuate Uterus Diagnosis Linked to Elevated Pregnancy Risks

A mild indentation of the uterine fundus identified prior to conception is associated with increased occurrences of gestational diabetes mellitus, fetal growth restriction, and abnormal umbilical cord insertion among women undergoing infertility treatment, according to a prospective cohort study published in Archives of Gynecology and Obstetrics. The investigation, conducted by researchers including Tatsuya Yoshihara and Osamu Yoshino, followed patients who received care between April 2022 and November 2025 and subsequently delivered at the study hospital. The clinical significance of arcuate uterine morphology has historically remained unclear because the American Society for Reproductive Medicine 2021 classification categorizes the variation as normal, prompting the investigators to evaluate whether its identification before pregnancy relates to subsequent perinatal outcomes.

To evaluate uterine shape systematically, the clinical investigators utilized preconception three-dimensional transvaginal ultrasonography, commonly designated as 3D-TVUS. The researchers applied an operational classification definition based on the American Society for Reproductive Medicine 2021 criteria. Specifically, arcuate uterine morphology was formally characterized by an indentation depth measuring less than 10 millimeters paired with a fundal angle of 90 degrees or greater. Through these standardized diagnostic parameters, the clinicians could objectively distinguish arcuate structural features from normal uterine anatomy in patients assessed prior to achieving pregnancy.

The study evaluated a prospective cohort of 228 women undergoing fertility treatment who completed deliveries at the investigative center. Within this total cohort, 41 women, representing 18.0 percent of the study participants, were diagnosed with arcuate uterine morphology on preconception 3D-TVUS examination. The remaining majority of the evaluated group comprised 182 women, accounting for 79.8 percent of the patient sample, who presented with normal uterine anatomy, establishing the primary comparison group for tracking perinatal complications.

Clinical evaluations revealed noticeable differences in perinatal outcome rates between the two uterine morphology groups. Gestational diabetes mellitus developed in 21 percent of the women in the arcuate uterine morphology cohort compared with 4.0 percent among those with normal uterine morphology. Similarly, fetal growth restriction occurred at a rate of 20 percent in the arcuate group versus 6.6 percent in the normal anatomy group. Abnormal umbilical cord insertion was documented in 34 percent of patients with arcuate morphology, whereas the normal uterus group experienced an abnormal cord insertion rate of 14 percent.

Following univariate comparisons, the researchers entered all perinatal outcomes that differed significantly between the cohorts into a multivariable logistic regression model. Within this statistical model, arcuate uterine morphology served as the dependent variable to determine whether the associations persisted when adjusted mutually for co-occurring outcomes. Even after mutual statistical adjustment, gestational diabetes mellitus, fetal growth restriction, and abnormal umbilical cord insertion each remained independently associated with the preconception identification of arcuate uterine anatomy.

The researchers also performed exploratory subgroup analyses stratified by placental implantation site across 183 women whose placental locations could be reliably evaluated. Among women with fundal implantation, fetal growth restriction (33% vs 5.4%) and abnormal umbilical cord insertion (75% vs 14%) were more frequent in those with arcuate uterine morphology, but these outcomes did not differ significantly with non-fundal implantation.

Arcuate uterine morphology identified on preconception three-dimensional transvaginal ultrasonography correlates with elevated risks of gestational diabetes mellitus, fetal growth restriction, and abnormal umbilical cord insertion, yet the predictive value and clinical screening benefit of preconception 3D-TVUS remain to be determined through further investigation.

Subject of Research: Perinatal outcomes associated with preconception arcuate uterine morphology diagnosed by three-dimensional transvaginal ultrasonography

Article Title: Preconception diagnosis of arcuate uterine morphology by three-dimensional transvaginal ultrasonography and subsequent perinatal outcomes in women undergoing infertility treatment: a prospective cohort study

Article References: Yoshihara, T., Okuda, Y., Miyashira, D., Ono, Y., Sasatsu, S., Ogi, M., Ogasahara, E., & Yoshino, O. (2026). Preconception diagnosis of arcuate uterine morphology by three-dimensional transvaginal ultrasonography and subsequent perinatal outcomes in women undergoing infertility treatment: a prospective cohort study. Archives of Gynecology and Obstetrics. https://doi.org/10.1007/s00404-026-08609-7

Image Credits: AI Generated

DOI: 10.1007/s00404-026-08609-7

Keywords: arcuate uterus, uterine morphology, three-dimensional transvaginal ultrasonography, 3D-TVUS, infertility treatment, gestational diabetes mellitus, fetal growth restriction, abnormal umbilical cord insertion, placental implantation, ASRM 2021 classification, prospective cohort study, perinatal outcomes, obstetrics, gynecology, fundal indentation, prenatal ultrasound