Fertility basics
The follicular phase runs from the first day of a period until ovulation. Rising FSH stimulates a group of ovarian follicles to grow, and usually one becomes dominant, maturing an egg while oestradiol levels rise and thicken the endometrium. This phase varies most in length between individuals and cycles, which is why overall cycle length can differ even when ovulation is normal.
Also known as: proliferative phase
Sources
- Indian Council of Medical Research (icmr.gov.in)
- Federation of Obstetric and Gynaecological Societies of India (fogsi.org)
Last reviewed: 9 September 2026. Written by the Antega Editorial Team. General information only — always follow the advice of your own clinic, doctor or pharmacist.