Combined pill

What are combined birth control pills?

They’re pills that combine two types of hormone: oestrogen and progestogen. 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 Microgynon, for example, the active ingredients are levonorgestrel 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.

How effective are combined birth control pills?

There are two ways of measuring how effective pills are at preventing pregnancy. One way is according to perfect use. This means you take the pill exactly as you should, every day, without making a mistake. The level of effectiveness of the combined oral contraceptive pill when taken like this is over 99%^[1]. So in a whole year, fewer than 1 in 100 women taking the combined birth control in that time will become pregnant.

The other way is typical use. This is when you take the pill but make realistic errors, such as forgetting the occasional pill or taking it late. It’s 91% effective when taken like this, which means about 9 in 100 women taking it over a year will become pregnant.

The best way to make sure the pill is effective then is to follow the instructions as closely as you can when you take it.

When to start taking the combined pill

It depends on whether you’re taking the pill for the first time, coming back after a break, or switching from a different type of birth control. If you’re using the pill for the first time, you can start on any day.

When you start using the pill on the first day of your period, you’re protected from becoming pregnant immediately — so you don’t need to worry about using a condom.

If you start using the pill after the first day of your cycle, you won’t be protected right away. Use a back-up birth control method (like condoms) for seven days while the pill starts to work.

Another option is the Sunday start approach. If you start taking the pill on the first Sunday after your period begins, you avoid withdrawal bleeding on a weekend (if you want to skip having your period on a weekend, this is the way to go).

When to start the combined pill if you’re already on birth control

You shouldn’t leave a gap when you’re switching from one birth control method to the combined pill. If you’re already taking a hormonal birth control pill, start your new prescription the day after you finish your last pill.

If you’re using a transdermal patch like Evra, start the pill a day after you’re due to take off the patch. If you’re using the vaginal ring, start the pill a day after you take out the ring.

If you normally have the Depo-Provera injection, you can start taking your pill up to 15 weeks after your last shot.

And if you have an IUD (copper or hormonal), you should begin your combined birth control pill pack a week before having your IUD removed.

In either of these cases though, it’s very important that you read carefully and follow the instructions in the patient leaflet that comes with your medication.