This section provides information on the risks and benefits of hormonal contraceptives.
Hormonal contraceptives are the most effective method of preventing pregnancy, and are associated with many health benefits that result from avoiding pregnancy and the termination of unwanted pregnancies. In addition, the hormonal contraceptive can reduce menstrual blood loss, relieve painful menstruation and may reduce the incidence of ovarian and endometrial cancer.
Hormonal contraceptives are available as combined (oestrogen plus progestogen) pills and patches or as progestogen-only pills, injections, implants and intra-uterine devices.
The benefits associated with using hormonal contraception far outweigh the side effects, which are rare, in the vast majority of women who use it.
Side effects – combined contraceptives
All combined oral contraceptives (COCs) are associated with a very small and rare risk of venous thromboembolism (VTE: dangerous blood clots in the veins), compared with no use. However, the risk of a blood clot from taking the pill is considerably smaller than the risk of a blood clot during pregnancy. Deep vein thrombosis (blood clots in the veins of the leg) and pulmonary embolism (blood clots in the lungs) are two types of VTE.
COCs contain an oestrogen (ethinylestradiol) and a progestogen component. The exact level of risk of VTE varies slightly according to the dose of oestrogen and the type of progestogen. Many studies have shown that for pills that contain the same dose of oestrogen, the risk of VTE is slightly higher for pills that contain the progestogens desogestrel or gestodene (the so-called ‘third generation’ pills) compared with those that contain the progestogen levonorgestrel (so-called ‘second generation’ pills).
In May 2011, an analysis of the available epidemiological data showed that the risk of VTE for COCs that contain drospirenone is higher than the risk for levonorgestrel-containing second generation COCs, and may be similar to the risk for desogestrel-containing or gestodene-containing third generation COCs. Product information for Yasmin is being updated accordingly.
Current key information for Yasmin
For women who want to start or switch contraception, levonorgestrel-containing pills have the lowest thrombotic risk and are the safest pill. However, any prescribing decision should also take into account each woman’s personal risk factors and any contraindications, including her experience with other contraceptive formulations.
All combined hormonal contraceptives should be prescribed with caution to obese women (BMI>30), or those with a higher baseline risk of VTE for other reasons.
The latest information on this issue is contained in the following article from Drug Safety Update (June 2011):
Yasmin: risk of venous thromboembolism higher than levonorgestrel-containing pills
If you have any concerns about your contraception, you should discuss them with your contraceptive provider but keep taking your contraceptive pill until you have done so. If you stop taking your pill, you will need to use another method of contraception, such as a condom, from then on as you otherwise risk becoming pregnant.
Longer term use of the combined hormonal contraceptive has also been associated with a small increase in the risk of cervical cancer:
Oral contraceptives and cervical cancer - 4 April 2003
For further information on the side effects of combined hormonal contraceptives refer to the patient information leaflet (PIL) that should accompany every pack of medicine. This is also available on the electronic Medicines Compendium website. (external link)
New advice – combined oral contraceptives (also known as 'the Pill')
The product information for combined oral contraceptive pills marketed in the UK is being updated with new advice on when you can start taking the Pill, and what actions to take if you miss a pill. The new advice follows a review of the evidence underlying the current guidance, which was performed by the MHRA and the Commission on Human Medicines (CHM). The updates will ensure that the advice is consistent between different brands of the Pill, and is in line with clinical guidelines. The following Public Assessment Report provides a summary of the review and the new advice.
Side effects – progestogen-only contraception
Depo-Provera is a progestogen-only contraceptive injection that causes a temporary thinning of the bones while it is being used. In November 2004 new research in teenage users resulted in a change to the information for prescribers and users:
Updated guidance on the use of Depo-Provera contraception - 18 November 2004
For further information on the side effects of progestogen-only pills refer to the patient information leaflet (PIL) that should accompany every pack of medicine. This is also available on the electronic Medicines Compendium website (external link).
The MHRA continuously monitors the safety and quality of medicines after they have been licensed. Most medicines work well and are acceptably safe and most people take medicines without suffering any side effects. You can report suspected side effects of medicines to us directly through our Yellow Card Scheme, online via the Yellow Card website or via telephone on 0808 100 352.
