Combined Oral Contraceptive Pill
Combined Oral Contraceptive Pill
There are several contraceptive pills available in Ireland. Most contain a combination of two hormones, oestrogen and progestogen. The progestogen-only pill or “Mini Pill” is described in a separate article.
What is it?
The combined oral contraceptive pill, often simply called “the Pill”, contains oestrogen and progestogen. There are different amounts of oestrogen and different types of progestogen depending on the particular pill.
How effective is it?
When used carefully, it can be more than 99% effective. All combined pills are equally effective – those with less oestrogen are just as good for contraception as those with higher doses of oestrogen.
How does it work?
It prevents ovulation (the release of an egg each month) and therefore fertilisation can not take place.
Who is it suitable for?
The combined contraceptive pill is suitable for most women. However those who get migraine with aura, have had blood clots in the past, are very overweight or have high blood pressure should not take this type of pill. Women who are 35 or older should not take this pill if they are smokers. Women who have had breast cancer or have a family history of breast cancer where there is a known or suspected genetic mutation should avoid contraceptives containing oestrogen.
Most women will have some side effects when they start taking the pill. This is due to the hormones in the pill, particularly the progesterone component. Common side effects include headaches, breast tenderness, mood swings, bloating, nausea and leg cramps. Decreased sex drive and acne can also occur. If you get any of these side effects, they usually settle within a few weeks. Very rarely, more severe side effects may occur. Please consult the back panel of this leaflet. See end of this article for a list of severe side effects.
How do I take it?
Take the first pill on the first day of your period and then continue to take one pill at approximately the same time every day to finish the pack. The vast majority of combined pills are in 21 day pill packs. At the end of the pack, take a 7-day break. During this time you will get a period. Then restart the pill after the 7-day break. A more recent innovation is a pill that has a 24+4 formulation – 24 active pills and 4 placebo (sugar) pills. For women who think they may not remember to restart pills after a 7 day break, this regimen may be useful.
When is it safe to have sex?
If you start the pill on the first day of your period, you are protected immediately. However, you may start up to day 5 of your period in which case you will not be safe for contraception until you have taken the first 7 pills i.e. a week later.
What if I forget to take a pill?
It depends how late you are in taking the pill. If you are less than 12 hours late, don’t worry. Just take the delayed pill as soon as you remember and further pills as usual.
If you are more than 12 hours late taking your pill, take the pill you have forgotten immediately, continue taking your pills at the usual time (this may mean taking 2 pills together if you have forgotten a pill for 24 hours), but remember that you are not safe for contraception for one week. If you do not have 7 pills left in your pack you should run 2 packs of pills together and not take the 7-day break. Continue to the end of the second pack and then take the usual 7-day break.
What else reduces the effectiveness of the pill?
If you have an upset stomach with vomiting and/or diarrhoea you may not be protected. Continue taking your pills but use another form of contraception until seven days after the stomach upset has settled. Most antibiotics do not interfere with the effectiveness of the pill. However if you are prescribed any medication, you should inform the doctor that you are on the pill so that s/he can advise you whether or not the medication will cause problems with the pill.
Do I need check-ups?
Yes. On the first visit we will prescribe the pill for 3 months and then review to see if you are having any problems or questions. If you are happy with the pill we will then give you 6- month prescriptions. If you are experiencing any side effects we will discuss changing to a different pill or other form of contraception to see if this is more suitable for you.
Contraceptive vaginal ring
NUVARING is a contraceptive device that is similar to the oral contraceptive pill in that it also contains oestrogen and progesterone. Therefore it is suitable for those who can take the combined contraceptive pill.
The ring is made of a flexible material that slowly releases hormones over a three week period. It is inserted into the vagina by the patient and is left in place for three weeks. The ring is removed for one week and then replaced with a new ring – similar to the seven day break with the contraceptive pill.
EVRA is a contraceptive patch that contains oestrogen and progesterone. One patch is applied to the skin per week. On week four no patch is applied – similar to the seven day break with the contraceptive pill.
Both Nuvaring and Evra are as effective for contraception as contraceptive pills. Women who do not remember to take pills on time may find these alternative delivery systems useful.
Rare oestrogen side effects
You should see a doctor immediately if you experience any of the following:
- Severe pain in one or both legs
- Swelling in one or both legs
- Sudden or severe chest pain or breathlessness
- Changed pattern of migraine
- Sudden loss of speech or sight
- Loss of power or sensation in a limb