Bilateral persistent fetal vasculature associated with holoprosencephaly.

A 3.26-kg neonate with a gestational age of 40 weeks presented with episodic hypothermia and seizures, but stable vital signs. Semilobar holoprosencephaly was seen on magnetic resonance imaging. Ocular examination revealed bilateral persistent fetal vasculature. As genetic testing was not contributory, toxic intrauterine environmental insulin causing neurologic maldevelopment was the presumed etiology.