When Does Ovulation Occur?


Ovulation: at what period of the cycle does it occur?

If ovulation usually occurs on the 14th day of a 28 day cycle , this does not mean that it always occurs at half cycle (ie, on the 15th day of a 30 day cycle). or the 16th day of a 32-day cycle, for example). The release of the egg occurs about 14 days before the next period (so on the 16th day of a 30 day cycle since 30-14 = 16) .

This is why we can not know the period when we ovulate only retrospectively (taking a calendar for example), at the time of the following rules. This is also why it is so complicated for women with irregular cycles to calculate their date of ovulation, not being able to anticipate the date of their next period. To succeed in identifying it, why not use the method of temperature curves or an ovulation test?

What happens on the day of ovulation?

After having passed the first phase (pre-ovulatory or follicular) of the menstrual cycle to prepare several eggs (on the 8th or 10th day of the cycle, only one of them continues to develop while the others stop progressing), the ovary will finally release only a mature oocyte , immediately snapped up by the fallopian tube. Ovulation is the expulsion of this egg . Some women feel slight pain or tugging. If the oocyte is not fertilized within 24 hours of life, it dies. If it is fertilized, it will still have to implant in the uterine lining after 6 days of progestation (development of the egg and descent into the uterine cavity). But again, fertilization does not necessarily rhyme with implantation (also called nidation). All you have to do is test to see if you are pregnant.

How long does ovulation last?

Dr. Joëlle Bensimhon, gynecologist and author of The Pregnancy for Dummies (Editions First) recalls that if ovulation lasts only 24 hours , the fertility period usually starts 4 days before the release of the oocyte and lasts until 24h after this one, that is 5 days in total . The lifespan of sperm in the female genital tract can be up to 7 days , it would be enough to have sex regularly 2 to 3 times a week to increase the chances of conceiving a baby. That's also why it's possible to get pregnant when you thought you were out of date!

And in case of absence of ovulation?

Unlike the copper intrauterine device (IUD) that does not prevent ovulation, but sperm access to the fallopian tubes and implantation of the egg in the uterine wall, the principle of the hormonal contraceptive (pill, implant, patch, injection, vaginal ring) is precisely to prevent this physiological mechanism from taking place by inhibiting in particular the hormones involved (FSH and LH). Some mild contraceptives however allow ovulation to occur, and play on other factors of fertility: cervical mucus and uterine lining.

Nevertheless, it often takes several months for the menstrual cycle to resume normal after the cessation of contraception. It may happen that no ovulation occurs during the first cycle without a pill, or that, on the contrary, several ovulations take place.

To note

There are also medical factors responsible for anovulation , or absence of ovulation ( polycystic ovary syndrome , hyperprolactinemia, chromosomal abnormalities, ovarian failure, early menopause …). In case of ovulation disorders over time, a hormonal assessment can guide the diagnosis of the doctor or gynecologist, and propose a possible treatment to regularize the cycles and promote ovulation.