Hormonal contraceptives

The different methods

Hormonal contraceptives can be broadly split into short-acting and long-acting forms. Short-acting hormonal contraception includes the combined and mini pill while the longer acting group includes the injection, implant and some hormone-containing coils. 

Here, we discuss the success rate of the various methods. For comparison, in a 12 month period of using no contraception at all, approximately 80-90% of women would fall pregnant whilst 10-20% would not.

Short-acting hormonal contraceptives

The combined oral contraceptive pill 

The combined pill is often just called ‘the pill’ and has two female hormones, progestogen and oestrogen. This pill works by stopping eggs being released, thickening the cervical mucus so sperm find it much harder to meet an egg and thinning the lining of the womb so that implantation is much less likely to occur. 

There are two kinds of packs available for the pill. With the first kind, you take a pill every day for 3 weeks. You then have a 1-week break where you bleed, like a period. After this, you will start a new pack.

With the second kind, you take 1 pill a day for 4 weeks. Some of these pills are inactive and when you take the inactive dummy pills, you’ll bleed like a period.

Possible side effects include:

• Headaches

• Nausea

• Breast tenderness

• Mood changes

• Blood clots, for example deep vein thrombosis

Success rate: over 99% effective if used as prescribed.

Vaginal rings

Vaginal rings contain the same hormones as the combined pill and it works in the same way. It’s easy to insert the ring into the vagina yourself, and it’s not possible to put it in the wrong position as long as it feels comfortable. You use the ring for 3 weeks, followed by a 1-week break where you have a bleed. You then insert a new ring.

It’s important to use the ring as prescribed and make a note on when it’s time to remove it.

Possible side effects include:

• Vaginal discharge

• Headaches

• Breast tenderness

• Blood clots, for example deep vein thrombosis

Success rate: 99% effective if used correctly.

The contraceptive patch 

The patch contains the same hormones as the combined pill and vaginal rings. You put a new patch on every week for 3 weeks, then you have a week where you don’t wear a patch and you’ll have a bleed like a period. The patch can be worn anywhere as long as your skin is dry, clean and not very hairy.

Possible side effects include:

• Headaches

• Mood changes

• Break-through bleeding

• Breast tenderness

Success rate: 91% effective if used correctly.

Progesterone-only pills (POP)

These pills (sometimes called the ‘mini-pill’) only contain the hormone progesterone and are a good alternative for people who are unable to tolerate the oestrogen that’s contained in the combined pill, for instance if you smoke, are overweight, over 35 or are breastfeeding.

It works in a similar way to the combined pill – by delaying ovulation, thickening cervical mucus and thinning the lining of the womb. This pill must be taken at the same time every day, with no break. 

Possible side effects include:

• Acne

• Breast tenderness

• Irregular periods

• Headaches

Success rate: 99% effective if used correctly.

Long-acting hormonal contraceptives

It can be hard to remember to take a pill or change a patch or ring on time. If you think this might apply to you then long-acting contraception may be more appropriate. It’s important to remember that these are fully reversible and not permanent.

Contraceptive injection 

The injection contains only one hormone, progestogen, and it works in a similar way to the other hormonal methods – by delaying ovulation, thickening cervical mucus and thinning the lining of the womb. It’s given by injection into a muscle every 12 weeks. 

Possible side effects include: 

• A delay in return to fertility

• Weight gain

• Change in periods

• Risk of bone thinning if used for a long period of time

Success rate: over 99% effective if injections are kept on time every 12 weeks.

Contraceptive implant

The implant is a thin flexible rod that is inserted into your upper arm, slowly releasing the hormone progesterone. It lasts 3 years before it needs replacing but it can be removed at any time. No one would know it was there by looking but you might be able to feel it under your skin. Your fertility will return to normal as soon as it is removed. 

Possible side effects include: 

• Headaches

• Nausea

• Breast tenderness

• Acne

• Stopped periods

Success rate: over 99% effective.

Intrauterine system (IUS) 

There are two types of coils – the copper (IUD) or hormonal (IUS). The IUS only contains progesterone. It works by thickening the cervical mucus and thinning the lining of the womb. 

An IUS requires a short procedure to fit and can be carried out by some GPs or a family planning clinic. A speculum (a device to open the vagina) is inserted and the coil is carefully placed inside the womb. Some strings hang down into the vagina so that the device can be easily removed and it’s a good idea to feel these from time to time to check that the IUS is still there. A partner would not be able to feel the coil during sex. 

It does need to be replaced every 3-5 years depending on the brand of coil used, although it can be removed at any point and fertility would return to normal, for most women, immediately. 

Possible side effects include:

• Acne

• Breast tenderness

• Mood changes

• Ovarian cyst

• Complications of insertion (for example an infection)

Success rate: over 99% effective.

Forgotten contraception?

If you miss a pill or forget to replace your vaginal ring or contraceptive patch in time, check the package leaflet which tells you what to do. It may be necessary to speak to a doctor who can advise you on the next steps. Use condoms as well for additional protection until you’re sure you’re getting reliable protection again from your hormonal contraceptive.

If you have unprotected sex after missing a pill or forgetting to replace your patch or ring in time, you may need emergency contraception.

Read more:

Methods of contraception
Non-hormonal contraceptives
Natural family planning
Emergency contraceptives 

How Livi can help

• Expert advice on switching to a new contraceptive method

• A video appointment to renew your oral contraceptive prescription. A Livi doctor can write you repeat prescriptions through your GP practice for up to 3 months if you’re already on the pill.