What is ovulation?

Understanding our bodies is essential for experiencing pleasure and making informed choices about reproduction (getting pregnant or preventing pregnancy). For those with a vagina, ovulation is a key process that starts at puberty. It's part of the menstrual cycle, where each month, an ovary releases an egg, making the days around ovulation the most fertile. 

How does ovulation work? 

Ovulation is part of the menstrual cycle. This is the monthly process that causes periods.  

All female bodies have two internal parts called ovaries. These are part of the reproductive system, and they sit just above the womb (uterus). Each ovary holds lots of tiny eggs. Each month, one of the ovaries will release an egg as part of the menstrual cycle. This is what ovulation is.  

The ovaries take it in turns to release an egg each month. After the egg is released, it will move down the fallopian tube (the things that connect the ovaries to the womb) and stay there for 1 or 2 days. If it meets live sperm during this time it will be fertilized and a pregnancy will begin.  

That’s why the days around ovulation are when pregnancy is most likely to happen. But pregnancy can happen any time sperm meets an egg. 

When does ovulation happen? 

Ovulation normally happens in the middle of the menstrual cycle. This means it happens about two weeks before a period starts. 

What age does ovulation start? 

Girls and anyone else with a vagina will start having menstrual cycles when they reach puberty. When this is will depend on your body. It tends to be around the age of 12. But it can be anytime between the ages of 8 and 16. 

What’s the difference between ovulation and menstruation? 

It’s confusing right? This is because ovulation and menstruation sound kind of similar, and they are both part of the reproductive cycle. But they are very different. 

To recap, ovulation is when an egg is released. 

To understand what menstruation is, you first need to know that the womb grows a lining each month. It does this so that, if an egg gets fertilized, it has somewhere safe and comfortable to grow into a pregnancy. 

Remember that little egg travelling down the fallopian tube? If it does not meet sperm as it travels, the lining of the womb will know it is not needed, and it will leave the body through the vagina. Amazing right?  

This is what a period is. Another name for it is menstruation. 

Did you know there are four stages of the menstrual cycle? Our periods and the menstrual cycle page explains them all. 

How is ovulation linked to pregnancy? 

You have the highest chance of getting pregnant on the day your ovary releases an egg and the days around it.  

What is really important to know is that sperm can live in the female reproductive system for up to seven days after sex. It can wait in the fallopian tubes ready to fertilize the egg.   

This means the seven days leading up to, and including, ovulation is the time when pregnancy is most likely to happen. Some people call this the fertile window or the seven-day window. 

Can I track when I ovulate so I don’t get pregnant? 

Some people track their menstrual cycle to work out when they are ovulating and when their seven-day window is. If they don’t want to get pregnant, they will use another type of birth control or not have sex during these seven days. This is called the rhythm method. It is a natural kind of birth control.  

It may sound good, but natural birth control is one of the least reliable ways to prevent pregnancy. That’s because menstrual cycles can be irregular. This can make it really hard to predict when ovulation is going to happen.  

Using another type of birth control, like the pill, injection, implant, coil or patch, is much more reliable. This video can help you work out which option is best for you. 

It’s also important to know that none of those things will protect you or your partner from sexually transmitted infections (STIs), including HIV.  

Condoms are the only things that can prevent pregnancy and STIs. They can be a fun part of sex too, if you know how to use them right – this video will show you how. Some people use a birth control method like the pill, and condoms too. This way they are doubly protected. 

So now you know all about ovulation. Understanding how your (or your partner’s) body works gives you the power to make informed decisions about pregnancy and enjoy a healthier, more confident life.