Answer
In someone with a womb, it limits oestrogen-driven thickening of the womb lining and reduces the associated risk of endometrial hyperplasia and cancer.
Sources for this answer
- NHSNHS · NHS medicine guidance
- Progesterone Besins 100mg Soft Capsules — Current selected SmPCemc · Summary of Product Characteristics
General medicine information. Follow the instructions for your own medicine and speak to a pharmacist or clinician about your individual circumstances.