Some woman want or need IVF but do not wish to undergo pharmacological stimulation of the ovary. This is not a problem, as natural cycle IVF is also possible. In fact, a natural cycle was used for the first baby born through IVF.
If you are ovulating and have regular cycles, you will visit the clinic for scheduled ultrasounds to monitor follicular growth. When the follicle reaches a diameter of 16 mm, you will be given a GnRH antagonist (to prevent unplanned ovulation) and scheduled for transvaginal oocyte retrieval (egg collection). At 20 mm in diameter, we will induce ovulation with hCG. After 36 hours, we will collect the egg, which will undergo IVF. The embryo produced will be transferred to the mother’s uterus two or three days after collection.
The pregnancy rate for natural cycle IVF is usually lower than stimulated IVF (25%). However, it has the advantage of avoiding twin pregnancies and is more affordable (fewer medications).