HormonePrescription only
Progesterone
Capsule, pessary or injection
Quick Summary
Progesterone prepares and supports the lining of the womb.
Fertility treatment
Preventing preterm birth
HRT
Medical Uses
Fertility treatment: Supporting early pregnancy.
Preventing preterm birth: In some women.
HRT: With oestrogen.
How it's taken
Use exactly as prescribed.
Your doctor decides the right dose for you and how long to take it.
Your doctor decides the right dose for you. Follow their instructions and the label.
Common Side Effects
Drowsiness
Sometimes.
Breast tenderness
Common.
Bloating
Sometimes.
Interactions
Some epilepsy medicines
Lower levels.
Critical Warnings
Blood clots
Report leg swelling or chest pain.
Specialist use
In pregnancy under medical care.
Sources and further reading
Last updated 21 October 2026. For more detail, see these trusted health organisations.
- Progesterone: drug information(opens in a new tab) · MedlinePlus, US National Library of Medicine