Is your ovulation always on day 14 of your cycle?

Hi, I'm Roeliene, chairwoman of Sensiplan-Nederland, 59 years old, married, and a mother of three adult children. At 20, a friend told me about Rötzer's symptothermal method. We found it super interesting and taught it to ourselves from this book. We charted our cycles in a notebook on graph paper! Later, I met people from the symptothermal method Sensiplan (a more reliable method) and became a consultant. The knowledge about the cycle has personally brought me a lot, and it is my great desire that all women and men in the Netherlands will gain this knowledge. In my opinion, it is as fundamental as reading and arithmetic, as it is about your own body!

Moodies gives us, as Sensiplan consultants, the space to take you on a journey into the world of the female cycle in a series of blogs. This first time, I'm kicking off with 'ovulation,' what can be learned about it?

Ovulation

The term 'ovulation' is familiar to everyone. You assume that there is an ovulation and a menstruation in every cycle, but did you also know that the basis of your cycle is actually your fertility? We often don't think about that much.
Every cycle, a number of eggs mature in your ovaries. When the time is right, your body selects the best egg, which is allowed to continue growing until ovulation occurs, so that this egg cell can eventually be fertilized. If the egg is fertilized, it travels, dividing cells, through one of the two fallopian tubes to the uterus, where the nascent embryo can implant in the uterine wall to continue growing into new human life.

Every cycle, your body does a lot of work! It builds up the uterine lining with nutrients so that a fertilized egg can implant. If no implantation occurs, the built-up uterine lining comes out again with menstruation. For every new life, a 'bed' is prepared anew each cycle, so to speak, by building up the uterine lining. And if no fertilization occurs during that cycle, the uterine lining is shed with menstruation, and the whole process starts again.

If the egg is not fertilized, the egg cell is simply absorbed back into the body. So it's not the case that the egg comes out with menstruation, which many people think.

How many ovulations do you have in your life?

At birth, as a woman, you have approximately 400,000 egg cells in each ovary, so about 800,000 in total! Of these, about 400-450 reach full maturation in your lifetime. So you have about 400-450 ovulations in your life.

When does ovulation occur?

Many people think it's always on day 14 of the cycle. That has also been taught in biology textbooks for a long time. It's not true!

The precise answer is: 12-16 days before your menstruation. So you can only look back afterwards to see approximately when ovulation occurred in your cycle. You never really know precisely; you would have to do an ultrasound every month.

Women's cycle lengths can vary considerably. Also, cycles in the same woman can be very different in length. Approximately half of women have 4-9 days difference in cycle length. And about the other half has a difference of 10-18 days or even more! Only about 3% of women have a difference of 1-3 days in their cycles. This means that if you want to 'calculate' when your own ovulation approximately was, you will often arrive at different days, with a margin of 5 days as well. 

Can you only get pregnant on the day of your ovulation?

An egg can only be fertilized for 12-18 hours. That's less than a day! But for fertilization, you naturally need sperm cells. These can live much longer, even up to 5 days. That would mean that you are truly fertile for about 6 days a month. However, these fertile days are not on fixed days, but they vary per cycle. So never use a calculation method to determine your fertile days!

Ovulation and hormonal contraception?

Having an ovulation and a menstruation means you are fertile. But there are periods in life when you prefer not to be fertile if you and your partner do not wish for children.

The idea of hormonal contraception is that your hormone balance is altered so that there is no longer an ovulation or that no uterine lining is built up, preventing implantation in the uterus. 

• The pill and also the ring, patch, and implant usually ensure that no ovulation takes place, meaning no fertilization can occur. Because little uterine lining is built up, the bleeding is often light; it is then not actually called a menstruation, but withdrawal bleeding.
• The hormonal IUD prevents implantation in the uterine lining because the uterine lining is not built up. With a hormonal IUD, ovulation usually does occur, so the egg can be fertilized. The fertilized egg cannot implant and then dies. With a hormonal IUD, you usually also don't have withdrawal bleeding.

Ovulation and methods that consider fertile days?

These methods (also called natural methods or fertility awareness methods) take your own cycle into account. You track your ovulation and the build-up of your uterine lining, and thus your menstruation. The purpose of these methods is to determine the fertile and infertile days in the cycle. To observe what happens. On fertile days, you either abstain from sex or use a condom.

One method, by the way, determines the fertile days in the cycle much more accurately than another. The reliability varies enormously. Most apps cannot always correctly identify ovulation and the corresponding fertile days. As you read above, there can be a very large margin in the timing of ovulation. This makes virtually all apps and cycle computers less reliable as contraception.

If you want to use a natural method with high reliability, it is advisable to choose the symptothermal method Sensiplan, which is currently the most reliable method for mapping your cycle with its fertile and infertile days and is as reliable as the pill. This method requires a learning period of three cycles with a Sensiplan consultant, so it is an investment of time. But after that, it takes little effort, and you will benefit greatly from it, even for a future desire to have children. You will then know very well how your own cycle works and when you have ovulated!