Pituitary magnetic resonance imaging abnormalities in young female patients with hypogonadotropic hypogonadism

OBJECTIVE: To elucidate the association between clinical and laboratory characteristics and pituitary magnetic resonance imaging (MRI) abnormalities in young female patients with hypogonadotropic hypogonadism (HH). METHODS: We retrospectively investigated a series of 74 female patients (age range, 14–42 years) with normoprolactinemic HH who underwent pituitary MRI. Pubertal milestones and hormonal features of patients with small pituitary glands (PGs) and space-occupying lesions were compared with those of patients with normal PGs. RESULTS: The overall frequency of abnormal PGs was 35.1%, with space-occupying lesions observed in 8 patients (10.8%), and small PG observed in 18 patients (24.3%). The mean serum gonadotropin level was not different between patients with and without pituitary MRI abnormalities (P>0.05). Space-occupying lesions were not associated with low gonadotropin levels, type of amenorrhea, or presence of secondary sex characteristics. The frequency of space-occupying lesions was higher in patients with interrupted puberty (25.0%) than in patients who did not go through puberty (4.8%) or had a normal puberty (9.8%), but were not statistically significant (P>0.05). Small PG was associated with low gonadotropin levels and type of amenorrhea (P<0.05). CONCLUSION: Clinically significant space-occupying lesions were not associated with low gonadotropin levels, type of amenorrhea, or presence of secondary sex characteristics. However, the frequency of space-occupying lesions was higher in patients with interrupted puberty than in patients who did not go through puberty or who with normal puberty.