The ovarian stimulation that takes place in an artificial insemination treatment is very gentle and lasts 8-14 days. During this period it is necessary to make a control by means of estradiol analysis and transvaginal ultrasounds in order to check that the hormonal medication works as expected.
The number and size of the follicles in the ovaries are observed and ovulation is programmed when there are between 1 and 3 follicles of about 18 mm. At approximately 34-36 hours after ovulation induction with hCG injection, artificial insemination takes place.
If more follicels have developed with the stimulation, it would be necessary to cancel the AI, as there would be a risk of causing a multiple pregnancy.