Why is micronised progesterone used in embryo transfer?

Progesterone changes the lining of the uterus so it can receive an embryo and helps maintain that lining after transfer. Fertility treatment can alter or bypass the body's usual hormone pattern, so a clinic may prescribe additional progesterone to provide support. It does not make implantation certain and does not confirm pregnancy. Mild discharge, breast tenderness, bloating or tiredness can occur, depending on how the medicine is used.

Use the prescribed form and schedule exactly as your fertility team explains. Vaginal and oral preparations are not interchangeable without advice. Continue the medicine until the clinic tells you to change it, including if you notice spotting or have a negative home test. Keep the planned pregnancy test appointment and tell staff about severe discomfort, medicines or a previous reaction.

Contact your fertility clinic urgently for heavy bleeding, severe or one-sided pelvic pain, fainting, marked abdominal swelling or shortness of breath. These symptoms can need prompt assessment after fertility treatment. Seek emergency help for collapse or severe breathing difficulty.

Ask why progesterone is recommended in your cycle, how to use it, what to do after a missed dose, which effects are expected and when treatment should stop. See [Micronised Progesterone](/materials/micronised-progesterone/) for related reading.