Ovulation

Ovulation: the most important event in the cycle. At ovulation, an egg, ready to be fertilized, is released from the ovary and picked up by the fallopian tube, and moved towards the uterus. But when does ovulation usually occur and when are you fertile? What happens after ovulation and how can ovulation be determined? Answers to these and more questions can be found in this article.

Ovulation takes place about 10-16 days before the next menstruation. Thus, it does not necessarily occur in the middle of the cycle and not necessarily between day 12 and day 16. Ovulation can also occur on cycle day 20, cycle day 30, or already on cycle day 10 – depending on the length of your cycle. This is important to know, both for contraception and if you want to have children! Therefore, counting days is not a reliable method to determine the fertile window in the cycle. It is important for the time of ovulation that a so-called follicle has matured sufficiently. A follicle is an egg cell surrounded by a membrane. The maturation phase of the follicle is variable and depends on whether the hormones in the cycle reach sufficient levels. The length of the maturation phase (also called the follicular phase) can range from 6 days to over 90 days.

The fertile window in the female cycle is determined by the maximum fertilization ability of sperm and the maximum fertilization ability of the egg. Sperm can survive for a maximum of 5 days in the uterus waiting for ovulation. The egg itself is capable of fertilization for only about 12-18 hours after ovulation. So the fertile period can be defined from 5 days before, up to and including the day of ovulation. This means that there are about 6 days in the cycle during which you can become pregnant during unprotected sexual intercourse. 

Before ovulation, about 10-20 follicles mature in the ovaries. A few days before ovulation, only the largest of them continues to grow. At ovulation, the membrane of the largest follicle bursts and the egg cell is released. It is now absorbed by the fallopian tube. The egg is now capable of fertilization for 12-18 hours. Movement of the fallopian tube slowly moves it toward the uterus. The shell of the egg remains in the ovary. 

Ovulation can only occur when at least one follicle has matured far enough and hormones reach sufficient levels to trigger ovulation. However, the formation of hormones is strongly affected by external influences. If stress is present, the maturation of the follicles can be suppressed by the brain. The maturation process is then interrupted for a short or long time. The follicles then remain in a partially matured stage. When ovulation is not triggered, it is common to see many semi-ripened follicles in the ovaries – often referred to as “cysts”. When the stress subsides and the brain turns the maturation of the follicles back on, ovulation may occur a few days later. However, the body may also abort or completely suppress the maturation process during chronic or repeated stress. If the maturation process is interrupted, there is often a slight bleeding that is triggered by a drop in the estrogen level. Accordingly, bleeding may occur without ovulation. If the brain completely suppresses the maturation process, this initially manifests itself in a long absence of bleeding. If bleeding does not occur for more than 3 months, this is called amenorrhea. 

Ovulation itself is the “bursting” of the egg membrane and the reception of the egg by the fallopian tube. This process takes only a few seconds. After ovulation, the so-called corpus luteum is formed from the egg’s shell. In the cycle phase after ovulation, the corpus luteum produces the hormone progesterone and thus maintains the built-up uterine lining. The formation of the corpus luteum after ovulation takes a few hours. By the time the corpus luteum begins producing progesterone, another ovulation may be triggered. This happens when two or more follicles have grown to a similar extent. However, once progesterone is produced a few hours after the first ovulation, no further ovulation can be triggered. Until the end of the cycle, you are no longer fertile.

The maturing follicles before ovulation produce the sex hormone estrogen. Estrogen causes a change in cervical mucus, cervix, and other body signs.

Rising estrogen levels cause the consistency of cervical mucus to change and also often increase the visibility of cervical mucus. It tends to become moister, wetter and in many tends to be transparent and spinnable. The appearance is comparable to raw egg white. The change in cervical mucus is thus a sign of the fertile phase in the cycle. 

In addition to the cervical mucus, the rising estrogen level also affects the cervix. This is higher during the fertile phase. It is open and soft – similar to the lips. 

Menstruating women often also notice an increased libido, radiant skin, more self-confidence, and a higher energy level in the phase before ovulation. These signs are also due to high estrogen levels.

In the days leading up to ovulation, you may also notice what is called ‘Mittelschmerz’ or intramenstrual pain. This is a slight pulling sensation similar to that experienced during menstruation, which can also radiate to the back and perineum. So far, it has not been scientifically clarified where exactly this pain comes from. Most of those who feel it notice it in the 2-3 days before actual ovulation.

Another sign of ovulation is ovulation bleeding or ovulation bleeding. This is light bleeding that is often observed more as brown spotting or very light bright red bleeding. The cause of ovulation bleeding has also not yet been definitively determined. In science, however, it is blamed on the sudden drop in estrogen levels.

If the egg is fertilized within the 12-18 hours, then this fertilized egg travels through the fallopian tube to the uterus for about 4-5 days. There it nests about 6-7 days after ovulation. Only at this time, the pregnancy hormone HCG is produced. This signals to the corpus luteum that implantation has occurred and that further progesterone must be produced to maintain the uterine lining. 

If fertilization has not occurred within 12-18 hours after ovulation, the egg perishes. It is broken down by the body while still in the fallopian tube. The corpus luteum perishes without a signal of implantation about 10-16 days after ovulation and the next menstruation is triggered.

Ovulation is the most important event in the menstrual cycle. Ovulation can only take place if the hormones reach sufficiently healthy levels beforehand. Therefore, the occurrence or absence of ovulation is an important sign of health, which should be given much more attention. By observing the body, your hormonal and cycle health can be determined and influenced by a healthy and stress-free lifestyle.