How the combined pill works
The combined pill, with its hormonal ingredients estrogen and progestin, impacts on the female cycle in several ways.
The natural menstrual cycle can vary from between 25 to 35 days. On average, the time from the beginning of the cycle – the first day of bleeding – until the day before the next period is 28 days. It can be roughly divided into two phases: the phase up to ovulation and the phase after ovulation. The cycle is controlled hormonally by a region in the brain called the hypothalamus, by a gland called the pituitary and by the ovaries.
The hormone dose is precisely regulated throughout the entire cycle and leads to the following processes in the body:
The beginning of each cycle is marked by monthly menstrual bleeding or period. This lasts for about three to seven days. Toward the end of bleeding, hormones stimulate several ova (eggs) to ripen in the ovaries. Usually only one ovum matures fully.
The beginning of each cycle is marked by monthly menstrual bleeding or period. This lasts for about three to seven days. Toward the end of bleeding, hormones stimulate several ova (eggs) to ripen in the ovaries. Usually only one ovum matures fully.
During ovulation, on about the 14th day, a protective layer (follicle), that up to now has surrounded the ovum, bursts. The egg is flushed down the Fallopian tube into the womb. For several hours, the egg can now be fertilized. At the same time – again under the influence of hormones – the lining of the womb is stimulated. It thickens and prepares for the implantation of a fertilized egg. Unprotected intercourse at this time can lead to fertilization and pregnancy. If the ovum is not fertilized during this period, the thickened layer is shed together with the inner layer of the womb during menstruation. This happens as part of monthly bleeding. Since this marks the beginning of every cycle, the first phase now begins again.
