Uterine Venous Malformation as a Rare Cause of Prepubertal Vaginal Bleeding

Vaginal bleeding is a common reason for the referral of young girls for pediatric endocrinology and/or gynecology consultations. A physical examination should be performed, with particular attention paid to breast development and growth acceleration suggestive of precocious puberty. In the absence of pubertal signs and a vulvovaginal cause of bleeding on physical examination, pelvic ultrasound is a reasonable, cost-effective first choice for imaging. We report here 2 rare cases of prepubertal uterine bleeding in young girls with an enlarged uterus on ultrasound, highly suggestive of precocious puberty but completely discordant with the concentration of estradiol, which was undetectable. Pelvic magnetic resonance imaging (MRI) and a dedicated ultrasound examination with a high-frequency probe made it possible to diagnose the rare condition of uterine venous malformation. In this clinical setting, discordance between conventional ultrasound features suggestive of precocious puberty and negative hormonal assessment results should lead to MRI. Indeed, MRI is the gold standard imaging tool for the diagnosis and evaluation of the extension of such venous malformations, which can be suggested using a high-frequency probe demonstrating venous myometrial ectasia.