Aim: To determine the frequency with which hyperprolactinaemic illness tends to resolve with time.
Study design: A retrospective case-notes review from a specialist endocrine unit in a provincial teaching hospital and tertiary referral centre.
Patients: Seventy women with hyperprolactinaemia referred to the unit in the 15 year period between May 1979 and May 1994. All those with a non-pituitary cause or with macroadenoma had been excluded, as were those who did not have high-resolution imaging, or who were on treatment at the time of referral.
Intervention: Intermittent course of treatment with dopamine receptor agonists according to individual need.
Endpoints: Latest serum PRL concentration in those who had discontinued treatment, and whether serum PRL tended to be lower in any particular group.
Results: There was a significant fall in median PRL concentration from 2000 (714-8000) to 1000 mU/l (220-5600) in the 31 women who had discontinued therapy (P < 0.0005), and serum PRL was normal (< 700 mU/l) in 11 of them. Serum PRL also fell to normal in three of ten women who had no treatment at all. Final PRL concentration was normal in 35% of women who had had at least one pregnancy during the period of follow-up compared to 14% who had not (P < 0.05).
Conclusions: These data confirm the findings of others that hyperprolactinaemia will prove self-limiting in up to one-third of women, and that pregnancy may be one factor which triggers a return to normal function.