2021 10 12 cycle tracker title 1

How the female cycle works

Women have up to 500 periods in their lives, but how often does our knowledge of the menstrual cycle really go beyond the basics? The basics of the follicular phase, ovulation and the luteal phase.

The menstrual cycle is the time between the first day of menstruation and the last day before the next period. Every month, an egg matures in the female cycle. During this time, the lining of the uterus prepares for the fertilised egg to implant in it; it becomes better supplied with blood and cushioned. Around the middle of the cycle, ovulation occurs, which is not so much a moment as a phase lasting several hours.

These processes are completely automatic and are controlled by certain hormones.

First half of the cycle: the follicular phase

In the beginning was the blood - because the first day of your period is also day one of the new cycle. A normal period can last between 2 and 7 days, with bleeding usually heaviest in the first two days. During this time a variety of symptoms can occur, including cramps, bloating, tender breasts and back pain. Symptoms can vary from day to day and from cycle to cycle - which, incidentally, is one of the Reasons is, which is why it can be useful to Track cycle.

While menstrual bleeding occurs at the beginning of this first cycle phase, the ovaries prepare for ovulation at the same time. Egg follicles mature in the ovary, one of which will usually become established. Meanwhile, the uterus, also known as the womb, builds up mucous membrane to prepare for the implantation of a fertilised egg.

Ovulation - the ovulation phase

After around two weeks, the follicle in the ovary bursts - this is ovulation - and the egg, which has grown inside the follicle, makes its way through the fallopian tube towards the uterus. From now on, existing (or newly arriving) sperm have around 24 hours to fertilise the egg. While there is a persistent rumour that ovulation occurs in the middle of the cycle, it actually occurs 12 to 16 days before the start of the next period. A woman with a 28-day cycle will ovulate in the middle (i.e. between days 12 and 16), but with a 32-day cycle it is likely to be on day 17 or 18.

Second half of the cycle: The luteal phase (corpus luteum phase)

After ovulation, the follicle that released the egg becomes the corpus luteum and releases the hormone progesterone. After ovulation, the progesterone level rises and the oestrogen level falls. If the egg is fertilised, the progesterone continues to rise. If there is no fertilisation, it falls. The corpus luteum in the ovary then regresses, the egg dies and is reabsorbed by the body. The lining of the uterus is shed with the next menstrual period. A new egg then matures and the cycle begins again.

Follicle maturation, uterine lining build-up and hormone development in a woman's cycle

So much for the theory. But theoretical knowledge and knowing your own fertile phases are often still two different things. We have developed femSense to help you with this. The combination of the patch with integrated temperature sensor and the smartphone app is particularly suitable for women who want to recognise their ovulation without much effort and determine the best time to get pregnant. And that is just one of the many advantages of our system!

blog banner en


Female cycle (2022)

Periods and fertility in the menstrual cycle (2022)

Normal Periods (2022)

Season of Love is here 💕

Finally fulfil your desire to have children with our smart ovulation tracker! More than 23,496 women have already become pregnant with us and YOU can be the next one! 🤰

20% save on our patches:


Become part of the femSense family and:

  • Enjoy exclusive offers
  • Exciting insights from our experts
  • Learn about your cycle and fertility