Understanding Periods

For most girls, the menstrual cycle begins between the ages of 10 and 16. This usually continues until a woman is in her 50s, by which time the supply of eggs will be completely exhausted, oestrogen levels will fall and ovulation will no longer occur.

Understanding the menstrual cycle is the best way of managing your period. Once you know this, you can predict when your next period is likely to be and prepare for it. Most women’s cycle’s can last anything from 26 to 32 days but it can be even longer. Every woman is different.

Your cycle starts from the first day you experience blood loss – your period –so to work out when you’re next due, always count from this day.

Planning for your period

Days 1-5
Your period starts as the lining of your uterus is shed. It may seem like you’re losing lots of blood, but don’t worry, in reality it’s only equivalent to a few teaspoons full. You might notice the colour of your flow changes too, from bright red to a darker brownish colour. The period itself usually lasts between 3-7 days.

Days 6-13
The hormone oestrogen causes the lining of your uterus to thicken in preparation for pregnancy, while your ovaries prepare an egg for release.

Day 14
One of your ovaries releases a mature egg. During this time if you have sexual intercourse and the egg is fertilised, you’ll become pregnant.

Days 15-20
The egg travels down your fallopian tube and your uterus builds up protein, sugar and blood supplies in preparation for the fertilised egg’s arrival. 

Days 21-28
Your hormone levels continue to rise, which can cause pre-menstrual symptoms such as bloating, mood swings and tender breasts. If the egg is unfertilised your period will begin.