During IUI and IVF cycles, while the woman is on medication for ovulation induction, it is important that the follicular growth be monitored by ultrasonography.

Transvaginal ultrasonography(TVS) is used for follicular monitoring. During the cycle, a TVS is usually done on day1 (baseline) and then repeated on day4/5, day8/9 and day11.

This helps in monitoring the number and size of the follicles, determining the day of the trigger injection(for rupturing the egg) and the day of the egg retreival for IVf and or the day for IUI.