The fertile phase in the female cycle

The female cycle, and especially the fertile phase, is a fascinating but complex affair. It is divided into different phases, which in turn are directed by different hormones and factors. It is therefore not too surprising that the question of how long the fertile phase of the woman’s cycle really lasts always comes up in one way or the other. Is the woman, as many claim, only fertile on a single day in the cycle? Or does the fertile phase in the female cycle extend to two or even five days? What’s true?

The fertile phase is the time in the female cycle when a pregnancy can occur. Many women think that they can get pregnant during the whole cycle. In fact, however, the egg can only be fertilized for up to 24 hours after it is released into the fallopian tube. So once ovulation has taken place, fertilization can only occur within this window of time. This is why it is so important to be able to estimate the time of ovulation. Strictly speaking, a woman is only fertile at this time. Under ideal conditions, sperm can survive in the woman’s body for up to five days. This extends the fertile phase, which is limited to just 24 hours, to up to six days. This means that, taking sperm viability into account, the five days before ovulation and the day of ovulation itself (due to the viability of the egg) can be defined as the woman’s fertile days. Unprotected intercourse within this phase is significantly more likely to result in conception than on other days of the female cycle.

Let’s start at the beginning: A healthy woman has two ovaries. The ovaries produce the hormones estrogen and progesterone. Each woman also has a limited reserve of eggs. Once the eggs are used up, no more eggs are produced. The woman herself has no influence on how many eggs are used up each month and how quickly this happens.

As soon as a woman has her first period, a few eggs mature each month. From these eggs that mature each month, a single egg fully develops and makes its way from the ovary to the uterus. This process is a fundamental part of the female cycle.
To ensure that the egg is well protected, it lies in a protective shell – also called follicle. The egg cell is allowed to mature in this shell. Certain hormones are responsible for this and ensure that ovulation eventually occurs.

The cervical mucus also changes before and during the fertile phase. It becomes more fluid, translucent and spinnable, which means that if you hold it between your fingers, it can be pulled into ‘threads’. Fertile cervical mucus ensures that the vaginal environment is less acidic, making it easier for sperm to survive. Just before ovulation, fertile cervical mucus has a whopping 96% water content and it protects, nourishes and ‘guides’ the sperm on their way to the egg.

As we already know, a few eggs mature each month. When ovulation happens, the one egg that has developed particularly well by the end of the follicular phase is ‘pushed out’ and makes its way through the fallopian tube to the uterus. Every now and then, two or even more eggs make it into the fallopian tubes – in the case of fertilization, this results in, for example, twins or triplets.

If you are wondering how you can actually recognize the fertile phase, we can reassure you: there are some signs that tell you that you are currently in your fertile phase. One of them is, for example, the already mentioned fertile cervical mucus. Of course, this requires that you get to know your body very well, observe your cervical mucus and consciously watch out for changes.
You can also tell when you are ovulating by a change in the cervix. At the beginning of the cycle, the cervix is rather firm and closed and protrudes into the vagina. You can feel it relatively well.
When a woman enters the fertile phase, she can no longer feel it so easily because the cervix moves upwards, becomes softer and opens slightly so that the sperm can reach the egg.

Some women also report experiencing abdominal pain during the fertile phase. They feel a pulling or stabbing pain in the lower abdomen during the days around ovulation, often on one side at about groin level. An increased libido is also often a clear sign that you are in the fertile phase. Yes, we rarely want to admit it these days, but nature and our biology still have us firmly in their grip. Many women tell us that they feel much more excited about sex around ovulation.

The luteal phase is the period after ovulation until the start of your next period. Generally speaking, the egg can be fertilized for about 12-24 hours after ovulation. A pregnancy could therefore occur only within this time frame. Of course, it is important to know exactly when you are in which phase of your cycle. To do this, it is necessary to get to know your own body & cycle well. A fertility tracker is of course a wonderful tool to help with this. If you know exactly where you are in your cycle you can determine the fertile phase.

Yes, because the egg can only be fertilised for up to 24 hours after ovulation. So if ovulation has taken place, fertilization can only take place within this window of time. Sperm can survive in the woman’s body for up to five days under ideal conditions. This extends the fertile phase to up to six days. Taking sperm viability into account, the five days before ovulation and the day of ovulation itself can therefore be defined as the woman’s fertile phase. Statistically, most pregnancies occur through sexual intercourse in the 5 days before ovulation.

Well, it certainly depends on the timeframe in question. Basically, however, it can be said that the probability of getting pregnant is quite low if sexual intercourse does not take place during the fertile phase. Of course, irregularities in the cycle and associated shifts in the fertile phase must always be taken into account. Ovulation does not always occur at the same time and does not last the same amount of time in every cycle. Just as cycles can vary greatly from woman to woman, this can also vary from cycle to cycle.