Oocyte is the name given to women’s immature eggs. Some of them will develop into mature egg cells (ovum) during the follicular phase at the beginning of the menstrual cycle.
Although you may have been born with several million, only a few hundred will reach maturity between puberty and menopause. They are known as the ovarian reserve.
Oocytes are precious cargo, so they are stored in protective bags consisting of a mass of follicular cells. Each bag forms a follicle and each month, several follicles rise to the surface of the ovary but only one of them will mature and hatch – otherwise known as ovulation.
It’s very difficult to determine exactly when ovulation will occur – even if your menstrual cycle is as regular as clockwork. People assume that it happens on day 14 (bang in the middle) but anything from stress to exercise can rewind your body clock, and it can change cycle to cycle.
If you’re trying to prevent pregnancy, you need to be careful around ovulation. Since this exact time frame is unpredictable, you risk getting pregnant – at any time of your cycle if you have sex without contraception.
During ovulation, the follicle in the ovary bursts and releases the mature egg cell. Ovulation occurs on varying dates, and therefore it can be difficult to predict it. Once released, the egg cell has a lifespan of 12 to 24 hours and it’s during this time that it can be fertilized by sperm.