How does ovulation work? – Understand the phases of your cycle
You probably know that ovulation is the time during your cycle where you can get pregnant. But do you know the phases of the cycle that leads up to ovulation and what happens after ovulation? Here you can learn more about how ovulation works and what characterizes the four phases of a woman’s cycle.
What ovulation means…
During the woman’s cycle, one (or in rare cases more) egg is discharged from the ovarian follicle and is ready to be fertilized by a sperm cell. This is called ovulation. Ovulation happens once during every cycle. A typical cycle is 28-32 days long although this varies from woman to woman. Ovulation happens around two weeks after the first menstrual day.
How does ovulation work? – 4 phases of the cycle
The length of the menstrual cycle is counted from the first day of a period and ends the day before the next period. The cycle can be divided into four phases. The length of each phase differs from woman to woman and depends on the total length of the cycle.
1) The menstrual phase:
The cycle starts on the first day of your period, which is the result of the previous cycle where the mature egg was not fertilised. This phase normally lasts around 4-7 days.
2) The follicular or pre-ovulatory phase:
This phase also begins on the first day of your period and normally lasts around 10-17 days. During these days, the level of your Follicle Stimulating Hormone (FSH) increases, which triggers your follicles to develop into mature eggs. Usually, up to thousands of follicles are released during every cycle, but only one follicle will develop into a mature egg and be released. Before the egg is released, the uterine lining thickens to prepare for implanting the mature egg into the uterus.
3) The ovulatory phase:
Ovulation occurs in the middle of the menstrual cycle in response to a peak in the level of oestrogen, right when the follicular phase is over. The oestrogen level triggers a release of the Luteinizing Hormone (LH). This hormone helps the egg to push through the ovary wall and into the fallopian tube within 24-36 hours where it is available for fertilisation. This is the optimal time for insemination. If the egg is fertilised, it will stick to the uterine wall after a few days of transportation.
4) The luteal phase:
The luteal phase lasts approximately 14 days and is the last stage in the cycle until the next menstrual phase begins unless fertilisation occurs. It marks a decrease in the level of FSH and LH. If the egg has not been fertilised, the body will shed the thickened uterine lining, and the menstrual cycle will start over.
Ovulation facts – did you know that…
- Women are born with approximately 1 million follicles (pre-eggs)
- Every month, up to thousands of follicles are released from the ovary but usually, only one follicle will develop into a mature egg
- A mature egg lives between 12-24 hours after leaving the ovary
- The menstrual cycle normally lasts between 28-32 days, but some women may have shorter or longer cycles
- Ovulation might occur even if your period has not occurred and vice versa
- Ovulation may occur on a different day each month and at different times during your cycle