In this cohort study with long-term follow-up, premenopausal bilateral oophorectomy was associated with an increased risk of developing parkinsonism, with a correlation of higher risk in younger age at surgery. Similar results were found for PD although only significant if oophorectomy was performed before age 43.
Why this matters
Estrogens are thought to have neuroprotective effects for dopaminergic neurons explaining the lower incidence of PD in women compared to men. This has been investigated in premenopausal women undergoing removal of both ovaries as preventative measure for ovarian cancer but with inconsistent results.
The findings of this study suggest that avoiding oophorectomy in women with average risk of ovarian cancer could decrease their risk of developing parkinsonism and PD.