The Period
Why the body regularly renovates
Imagine your body preparing a cozy guest room each month. Fresh bed linen, everything nicely arranged – for a guest that might arrive.
The guest? A fertilized egg.
If nobody arrives, the room is prepared anew for the next potential guest. And that is exactly where the period begins.
What's behind it
During the cycle, the uterus builds up a soft lining with a rich blood supply. That is where an early embryo could implant after fertilization.
If no pregnancy occurs, certain hormone levels drop. The upper layer of the uterine lining detaches and leaves the body together with blood and other fluids through the vagina.
That is menstruation – also known as a period.
Can it hurt?
Yes, that can happen – but it does not have to. The uterus has a strong muscular layer that contracts during menstruation. This can feel like a pulling sensation or cramps in the lower abdomen.
Some feel almost nothing, others have stronger discomfort. If you experience unusually severe or new pain, it is wise to have it medically evaluated.
How long does it last?
Often around three to seven days. But not every period is the same: duration, heaviness and symptoms can vary from person to person and from cycle to cycle.
Scientific background
- Physiology of the Endometrium and Regulation of MenstruationCritchley HOD et al. Physiol Rev. 2020. PMID: 32031903.
- Menstrual physiology: implications for endometrial pathology and beyondMaybin JA, Critchley HO. Hum Reprod Update. 2015. PMID: 26253932.
- Dysmenorrhea, a Narrative Review of Therapeutic OptionsKirsch E et al. J Pain Res. 2024. PMID: 39161419.
The contents are for general educational purposes and do not replace medical advice.