How does the pill work?

The pill is relied on by millions of women across the UK but most of the time we don’t stop to think about how it actually works. On a basic level, the hormones in the pill make changes to your natural menstrual cycle to ensure pregnancy cannot take place.

What’s in the pill?

Progesterone and oestrogen are the two types of hormones that are found in the pill. These occur naturally in the body and have many essential functions, which include the menstrual cycle and ovulation. The type of hormones in the pill is synthetic versions of these hormones. During the natural monthly cycle, the levels of these hormones would rise and fall as the ovaries release an egg, preparing the body for pregnancy and then shedding the womb lining during your period.

In contrast, synthetic hormones maintain a consistent level of hormones in your body to prevent these actions.

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What do the hormones in the pill do?

There are three main effects that the hormones in the pill have inside the body- all of which work together to prevent pregnancy:

Preventing ovulation- when your ovaries release an egg each month ready for fertilisation, this is known as ovulation. The pill stops this from happening, so without an egg to fertilise, pregnancy cannot occur.
Thinning the womb lining- after the egg is released, the lining of the womb thickens, ready to receive a fertilised egg. The hormones in the pill have a thinning effect on this lining, meaning that if fertilisation were to occur, the egg wouldn’t be able to embed itself.
Thickening the cervical mucus- in addition to this, the pill also causes the mucus surrounding the cervix to thicken which makes it difficult for sperm to be able to get through, in turn preventing them from being able to fertilise an egg.

Together, this makes the pill highly effective in preventing an unwanted pregnancy. However, this will rely on you taking the pill correctly.

How do I take the pill?

The best time to start taking the pill is on the first day of your period. This way, it will start to work right away and you’ll be protected from pregnancy from day one. Each pill in the packet will be marked with the day of the week to help you keep track of it. You should take one at the same time every day until you reach the end of the pack (which is a 3 week period).

After this, wait 7 days until you start another pill pack. If you forget to take the pill, take the forgotten one as soon as possible and ensure you take the rest correctly that month. If you forget more than one, you’ll need to use extra contraception for 7 days as you could be at risk of pregnancy.