Everything you need to know – Progestogen-only pill (POP)


by Maddie Braidwood · Aug 28, 2020

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Reviewed by Dr. Melanie Davis-Hall on Jun 1, 2023

Progestogen-only pill graphic
What is the progesterone only pill? The progestogen-only pill, aka progesterone only pill, POP or 'mini pill', is one of the most frequently reviewed methods at The Lowdown. Funnily enough, it only contains one hormone progestogen in it, unlike the combined pill which also contains oestrogen. It's very commonly used and considered very safe for most women.

How effective is the progestogen-only pill?

The progestogen-only pill, better known as the progesterone only pill, mini pill or POP, is a form of contraceptive pill which contains synthetic progestogen, similar to progesterone naturally produced by the female body. It is often used by women who are unable to use combined contraception which contains oestrogen, such as if you are breastfeeding or have a history of migraines.

Designed to be taken at the same time every day, the mini pill is one of the more popular contraceptives with common brands including Lovima, Cerelle, Cerazette, Norgeston and Noriday.

The progestogen-only pill is 99% effective if taken as directed at the same time each day. But, if this mini pill is taken in a ‘typical’ way, i.e not strictly at the same time each day, its effectiveness drops to 92-93%.

How does the progestogen-only pill work?

It prevents pregnancy by making the fluid in your cervix thicker (which makes it more difficult for sperm to enter the womb) and preventing the lining of your womb thickening enough for a fertilised egg to implant into it. The progestogen-only pills with desogestrel or drospirenone in them (so all of them except Micronor, Noriday and Norgeston) can also stop ovulation.

How do I get started on the progestogen-only pill?

If you get your pill via an NHS prescription through your GP, nurse or sexual health clinic, your doctor or nurse may check your medical history, any medicines you take and make sure that you’re not pregnant. You can also buy the progestogen-only pill through pharmacies – The Lowdown has its very own ordering service! Our pharmacists will check your medical history through our short online questionnaire. 

There are two established types of progestogen-only pill:

There are normally 28 pills in a pack, and unlike the combined pill you do not have a break between packs. It’s really important you reliably take the progestogen-only pill at the same time every day. 


If it helps, keep your pill packet somewhere you use or look at every day (like by your toothbrush) to remind you to take it, or set an alarm on your phone. You will normally be given a prescription for the pill for three months or up to one year at a time. If you want to read experiences from our Lowdown users, check out our progesterone only pill reviews.

How quickly does the progestogen-only/mini pill protect me from pregnancy?

Most women can start these pills at any time in their period cycle if they are sure they are not pregnant. If you start these pills within the first 5 days of you menstrual cycle (within the first 5 days of starting your period), you will be protected from pregnancy straight away. At any other time in your cycle you will need to use condoms for two days until you’re covered. There are special instructions for starting the pill if you have just had a baby, abortion or miscarriage.

What about the new drospirenone pill – Slynd?

There is soon to be a new type of progestogen-only pill available in the UK called Slynd! This POP contains 4mg of drospirenone, another type of synthetic progestogen, and is taken as 24 daily active pills followed by four hormone-free placebo pills (then repeat).

When starting the drospirenone POP additional contraceptive precautions (i.e. condoms) are required unless it’s started on day 1 of a natural menstrual cycle, day 1 after abortion or by day 21 after childbirth. If started at any other time, additional contraceptive precautions are required for 7 days until the pill provides protection against pregnancy. 

In contrast to the desogestrel and traditional POPs, the drospirenone POP is considered missed if you’re more than 24 hours late taking it. This means more than 48 hours after the last pill was taken or more than 24 hours after a new packet should have been started after 4 days of sugar pills (the hormone free interval).

How do I come off the progestogen-only pill?

Stopping the pill is easy – you just stop taking it. As soon as you stop taking it, you’re no longer protected from pregnancy. If you want to switch to another method it is best to discuss this with your doctor or nurse before stopping your pill. You can also read our blog on switching contraception for more info. Check out our survey results to see how long it took most women’s cycles to return to their definition of ‘normal’, and read up about after effects they’ve experienced.

Pros of the progestogen-only pill

  • Doesn’t interrupt sex
  • Can use it when breastfeeding
  • Can use at any age – even if you are over 50 or are over 35 and smoke (reasons you can’t taken oestrogen containing contraceptives)
  • It’s useful if you can’t take the hormone oestrogen, which is in the combined pill, contraceptive patch and vaginal ring
  • It can stop your periods or make them lighter, less frequent and less painful
  • It may help with the symptoms of premenstrual syndrome

Cons of the progestogen only pill

  • Vomiting and diarrhea will impact on how the pill is absorbed into your body. If you’re sick within 3 to 4 hours of taking the desogestrel or drospirenone POP (or 2 hours of taking the traditional POPs) you’ll need to take another pill straight away and the next pill at the usual time. 
    • If this replacement tablet is not taken within 3 hours (traditional POP), 12 hours (desogestrel POP) or 24 hours (drospirenone POP) of the time at which the original pill was due, missed pill rules should be followed. Check out our missed pill calculator or your pill packet for more info.
    • If you’re sick or have severe diarrhea for longer than this, check your pill packet for what to do next – and use condoms or abstain if you have any doubts.
  • Some medicines and antibiotics (like rifampicin and rifabutin, St John’s wort and anti-epilepsy drugs) change the way your body digests the pill, speak to your pharmacist for advice if you start a new medicine whilst taking the progestogen-only pill
  • The POP doesn’t protect you from sexually transmitted infections so remember you need to use condoms for this
  • There may be an association between current or recent hormonal contraception use and breast cancer, however, any potential increased risk appears to be small.

Possible side effects

These include the areas that are reported most frequently by reviewers at The Lowdown: 

  1. Mood changes (60%)
  2. Spots / acne (59%)
  3. Breast pain / tenderness (55%)
  4. Headaches (54%)
  5. Vaginal discharge (53%)
  6. Womb cramps (48%)
  7. Enlarged breasts (44%)
  8. Back pain (41%)
  9. Vaginal bleeding (40%)
  10. Vaginal dryness (38%)

Some users also report changes to sex drive or libido. Most of these are temporary are may settle within the first few months. You should contact your GP or nurse if they persist or are problematic.

The development of small fluid-filled sacs (cysts) on your ovaries are also a possible side effect– they are usually harmless and disappear without treatment.

If you do become pregnant while you’re using the POP, there may be a small risk of having an ectopic pregnancy. 

Will the progestogen-only/mini pill affect my periods?

The progestogen-only pill can affect your periods. They may become lighter, less frequent or stop altogether, which may be beneficial. They may also become irregular or prolonged or you may experience spotting between periods.

Who should use it?

Women: who:

  • can remember to take a pill regularly
  • can’t or don’t want to take oestrogen containing contraceptives

Who shouldn’t use it?

Women who:

  • think they might be pregnant
  • don’t want their periods to change
  • take other medicines that may affect the pill
  • have unexplained bleeding in between periods and sex
  • have had heart disease or a stroke, liver disease or breast cancer
There are some additional considerations for women who are considering the drospirenone POP due to a risk of an increase in potassium levels in the blood in susceptible individuals (e.g. those with kidney disease). Your healthcare professional will check this with you. 

What if I miss taking a pill?

Missing or forgetting to take a pill has happened to the best of us. Check out our missed pill calculator which will help you with what to do, depending on how many you’ve missed and where you are in your pill packet. We’ll update this with the drospirenone pill rules when this becomes available in the UK! If you have any doubt, then make sure you use alternative contraception such as a condom or don’t have sex until you’re protected and speak to your pharmacist.

Where can you get the progestogen-only pill?

In the UK, you should be able to get a free NHS prescription for the progestogen-only pill in most contraception clinics, sexual health clinics, GPs surgeries, and some young people’s services.

The progestogen-only pills Lovima and Hana are available over the counter from the pharmacy (ie without a prescription).

You can buy most brands of the progestogen-only pill through us at The Lowdown!

  1. FSRH. FSRH Clinical Guideline: Progestogen-only Pills. 2022
  2. MHRA. First progestogen-only contraceptive pills to be available to purchase from pharmacies. 2021

  3. FSRH. FSRH Response to new study on use of CHC and POC and breast cancer risk. March 2023

Maddie is an English Language and Linguistics graduate who is passionate about writing. She writes fun and informative content on the weird and wonderful sides of contraception!