Induced and spontaneous uterine leiomyomas in animal models: a scoping review

To map the experimental models of induced and spontaneous uterine leiomyomas (UL) in animals, describing induction techniques, evaluation methods, advantages, limitations, and research gaps.

We conducted a systematic review of studies published between 2004 and 2024 with in-vivo animal experiments reporting UL induction or spontaneous occurrence. Data were extracted on animal species, sample size, induction methods, confirmation techniques, and reported advantages or disadvantages.

A total of 56 studies were included. Rats and mice were the most frequently used species. Induction methods comprised hormonal administration, genetic predisposition, chemical exposure (monosodium glutamate), ischemic injury, external stimulation, cell transplantation, xenotransplantation, and spontaneous development. A critical finding that emerged was that 60.7% of the studies failed to report confirmation of UL induction. Among the 22 studies that reported confirmation, caliper measurement was the most frequently used technique. This widespread lack of methodological rigor significantly undermines the credibility and reproducibility of many published models.

This scoping review highlights not only the heterogeneity of UL animal models and the lack of standardized induction and evaluation protocols, but also identifies a critical gap in induction validation reporting that compromises the foundation of preclinical research in this field.