What are combined birth control pills?
They’re pills that combine two types of hormone: oestrogen and progesterone. These hormones affect how and when your body prepares for pregnancy.
There are several different types of combined birth control pill and they’re all just about equally effective at preventing pregnancy. However, some contain higher doses of hormones than others, or use different types of progestin and oestrogen. This means one pill might be ideal for easing specific PMS symptoms, while another pill works great for women who are extra-sensitive to hormones.
It can feel a bit overwhelming, so we’re here to help.
How does the combination pill work?
The combined pill works in three ways to prevent pregnancy. Here’s the big one: it stops ovulation. That’s when your ovary releases an egg, and it happens once a month. Each egg has the chance to become fertilised, leading to pregnancy. If fertilisation doesn’t happen, the lining of your womb breaks down and the whole thing happens again next cycle (lots of fun, we know).
Because the combined birth control pill stops ovulation, your chances of becoming pregnant are significantly reduced.
The combined birth control pill also protects you by making the mucus in your cervix thicker. “Thick mucus” isn’t something you normally want to hear but in this case, it’s great news. When it’s thicker, sperm have a much harder time reaching the egg.
The pill also makes your uterine lining thinner. This lining builds throughout the month and then breaks down during your period. When you’re using birth control, the lining doesn’t build in the same way. And so the period you have while taking the pill should be shorter, lighter and more predictable.
Which contraceptive pills are combination pills?
Any that contain two active ingredients, a progesterone and an oestrogen. To find out if your pill is a combined pill, just check the active ingredients.
In the leaflet that comes with your pill, the ingredients should be clearly listed at the top underneath the name of the drug. For combined pills you should see two ingredients, front and center, that are progestin and oestrogen.
With Loestrin, for example, the active ingredients are norethindrone acetate and ethinyl estradiol. This pill is clearly stated as a progestin-oestrogen combination.
We offer a range of combined birth control pills, so there’s plenty of choice for you. But if you can’t take combination pills, for any reason, it’s important to share this with us for your safety.
Medically reviewed by
Dr Daniel Atkinson
GP Clinical Lead
on August 02, 2022.
This page was medically reviewed by Dr Daniel Atkinson, GP Clinical Lead
on August 02, 2022. Next review due on August 01, 2024.
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