Frozen embryo transfer in a natural cycle

Instead of creating a fully controlled hormone schedule, the clinic watches the menstrual cycle as it develops. Ultrasound can assess the womb lining, while blood tests or other monitoring may help identify the hormone changes around ovulation. The transfer date is then matched to the age of the embryo being used.

Some people have a clear, predictable ovulation pattern and are suitable for this approach. A cycle may need to be changed or postponed if ovulation cannot be confirmed, the lining does not develop as expected, or the timing is uncertain. The plan is individual rather than fixed to one calendar day.

Record the first day of your period and attend monitoring appointments on the dates given by your fertility team. Tell the clinic about medicines, supplements, unusual bleeding, or a cycle that is later or earlier than expected. Follow instructions about when to begin any prescribed progesterone; details may differ depending on whether ovulation has been confirmed.

After transfer, continue medicines exactly as directed and keep the clinic’s date for pregnancy testing. Normal gentle activity is usually compatible with care, but ask about strenuous exercise, travel, and work demands if your team has given restrictions.

Contact your fertility clinic promptly if you have heavy bleeding, severe or worsening pelvic pain, faintness, fever, breathing difficulty, or marked abdominal swelling. Also call if you cannot take a prescribed medicine, miss a dose, or develop symptoms that concern you after transfer. These symptoms do not by themselves show whether treatment has worked, but they should be assessed.

Ask how ovulation will be detected, which appointment confirms the transfer date, what happens if ovulation is late, and when to start or stop progesterone. You can also ask how the embryo is matched to the timing of your cycle and which symptoms require an urgent call.