Menstrual cycle and menstruation

Menstrual cycle is the period between two bleedings (menstruation) and the first day of bleeding is the first day of the cycle. On the average the cycle is 28 days however it can take longer or shorter than that.

Menstruation (menstrual bleeding, period, cycle, menses) is normal vaginal bleeding taking place once per month. The word is derived from the Latin term menses, meaning “month” 

Every woman will menstruate. The first period usually occurs between 11 and 14 years of age but can occur earlier or later and it keeps repeating until approximately 50 years of age when menopause occurs. However, it is possible for menopause to occur earlier or later too.


Why does menstruation occur?

Each month, woman’s body prepares for pregnancy. This encompasses growth of uterine mucosa which is creating a place for the fertilised egg cell to be inserted. If the fertilisation does not happen, the mucosa is not needed and is being ejected – this is what creates menstrual bleeding. Thus, menstrual product is a mixture of blood, cells and tissue pieces.


What is the duration of the menstrual cycle and menstruation?

The length of the cycle (from the first day of bleeding to the first day of the next bleeding) varies, usually between 26 to 32 days, 28 days on the average. It is important to keep the cycle regular so you should use a calendar and register the dates of bleeding, comparing the length of the cycle several months back. If the bleeding occurs at regular intervals, the cycle is regular, otherwise it is irregular.

The bleeding itself can take somewhere between two to eight days, but between 4 and 6 on the average. The bleeding is not uninterrupted, it starts and stops in different intervals, although this is not readily visible without closer inspection. On the average, the blood loss over one period is 4-6 spoonfuls or between 60 and 90 grams.


Irregular menstrual cycle

Irregular menstrual cycle is normal at the start of the reproductive age, after the onset of menstruation. Some time is necessary to reach the stabile and regular rhythm of hormone production. Also, some 30% of all women have moments in their life when the cycle is irregular – the bleeding misses the date or starts earlier than expected, or there is bleeding between two regular bleeding dates. This can be caused by mild hormonal imbalance, but the causes can be much more serious.

Thus, in the event of irregular cycle, or bleeding between two cycles, you should see your doctor.


Pre-menstrual syndrome (PMS)

 It is not uncommon to have different symptoms before and during the bleeding: physical and emotional. These may include: cramps in lower abdomen, lower back pain, sensitive breasts, stronger appetite, mood swings, emotional instability, headaches and tiredness.

PMS can appear in the period between ovulation and menstruation, regardless of the woman’s age. It is not uncommon that these symptoms are strong enough to prevent the woman from going to work or school and force her to take painkillers. If you yourself have a very pronounced PMS, you can talk to your gynaecologist about some treatment that can alleviate the symptoms.