Uterine fibroids in Latinas: findings from the Environment, Leiomyomas, Latinas, and Adiposity Study

Latinos are among the fastest growing populations in the United States. While previous work indicates racial/ethnic differences in fibroid prevalence, little is known about the prevalence of this condition among Latina females in the United States.

To determine the prevalence of fibroids among reproductive-aged Latina females and identify associated factors in this population.

Environment, Leiomyomas, Latinas, and Adiposity Study is a prospective cohort study of Latina females, based in Southeast Michigan, and conducted using Community Based Participatory Research (CBPR) principles. Data were collected between October 2017 and October 2022, a community health clinic in Detroit, MI and at the University of Michigan's Center for Reproductive Medicine in Ann Arbor, MI. Eligible participants self-identified as Hispanic or Latina; were assigned female sex at birth; were aged 21 to 50 years at enrollment; could speak, read, and write in either English or Spanish; were not currently pregnant; and did not have an implantable electrical device, history of malignancy, or other conditions requiring chemotherapy or radiation. Fibroid symptoms were not a requirement of participation. Fibroid prevalence was rigorously established via self-reported medical history and expert administration of transvaginal ultrasounds. Participant features-including demographics, health, acculturation level, and other factors of interest-were established via surveys, interviews, and in-person measurement.

Among Environment, Leiomyomas, Latinas, and Adiposity Study participants who completed a vaginal ultrasound (N=609 of 621 eligible), the mean age was 37.3±7.0 years and 68 (11.2%; confidence interval, 8.6%-13.8%) presented with fibroids. The majority had a single fibroid (75.0%), while 25.0% had 2 or more. The mean size of the largest fibroid-most often intramural (80.9%)-was 2.9±1.2 cm in diameter. Fibroid prevalence was found to be higher in older age groups, rising from 3.5% (confidence interval, 1.4%-10.0%) among participants aged 21 to 30 years, to 8.3% (confidence interval, 4.9%-11.7%) in those aged 31 to 40 years, and 18.7% (confidence interval, 13.3%-24.1%) in those aged between 41 and 50 years (P<.001). Logistic regression models indicated that fibroid presence was associated with younger age at menarche (adjusted odds ratio, 0.84; 95% confidence interval, 0.72-0.99) and increasing gravidity (adjusted odds ratio, 0.80; confidence interval, 0.66-0.97). Findings indicated no significant association with parity (adjusted odds ratio, 0.85; confidence interval, 0.68-1.07).

Environment, Leiomyomas, Latinas, and Adiposity Study is among the first prospective studies of its size to use an ultrasound confirmation approach to establish fibroid prevalence among Latina females in the United States. Our findings suggest the prevalence of fibroids among Latina females is much lower than previously reported in the literature and markedly lower than that in Black and White women. More research is needed to understand why burden may be lower in this population and how such findings can be used to benefit all women.