Premature Ovarian Failure in French Canadian Leigh Syndrome.

In all surviving girls with Leigh syndrome, French Canadian variety, a mitochondrial disease, we detected premature ovarian failure, manifested as absent or arrested breast development, lack of menarche, high follicle-stimulating hormone, a prepubertal uterus, and small ovaries. Pubertal onset and progression should be evaluated in girls with mitochondrial diseases.