If you would like to know more about the benefits of the progestogen only pill (POP) contraceptive pill, and the risks and side effects of the progestogen only pill, read the following article for more information.
The progestogen only pill (POP) is an effective method of contraception if used correctly. It is commonly used when the combined pill (which also contains oestrogen) is not suitable. For example, by breastfeeding women, or women who are over 35 and smoke.
How does the POP work?
The POP contains a progestogen hormone. This is similar to the progesterone hormone made by the ovaries. It works mainly by thickening the mucus made by the cervix which forms a 'mucus plug' in the cervix. This stops sperm from getting through to the uterus (womb) to fertilise an egg. The POP also makes the lining of the uterus thinner. This makes it unlikely that a fertilised egg will be able to attach to the uterus. It also has some effect on the ovary and ovulation may not occur (the release of egg each month).
How effective is the POP?
The POP is 99% effective if used correctly. This means that 1 woman in 100 using the POP correctly will become pregnant each year. Correct use includes taking it at the same time every day. If it is not taken correctly, more women will become pregnant. Some studies suggest it may be less effective in women who weigh more than 11st (70kg).
What are the advantages of the POP?
It does not interfere with sex. You can take it when you are breastfeeding. The risks associated with the oestrogen in the combined pill (eg blood clots) do not occur. It can therefore be used by some women who cannot take the combined pill. For example, women over 35 who smoke.
What happens to your periods when you take the POP?
The effect on periods can vary. Some women have regular normal periods. Some have irregular periods which may be longer and heavier, or shorter and lighter, than usual. Some women continue to have regular periods but may have occasional 'spotting' between periods. Some women have very infrequent, or no, periods. Irregular or unpredictable periods can be a nuisance, but is of no medical concern. Keep taking the POP everyday, including when you have periods.
Are there any side-effects with taking the POP?
Side-effects are uncommon. If one or more do occur, they often settle down over a couple of months or so. Examples of possible side-effects include: headaches, mood swings, weight gain, reduced sex drive, fluid retention, increase in acne, and breast discomfort.
Are there any risks with taking the POP?
If you become pregnant while taking the POP, you have an increased risk of ectopic pregnancy (pregnancy inside the fallopian tube and not in the uterus). This is uncommon, but serious. If you develop pain in the lower abdomen (tummy), particularly shortly after a missed or light period, see a doctor quickly. This is to check an ectopic pregnancy has not occurred.
The POP also increases the risk of developing small, benign (non-cancerous) cysts in the ovary. These are not serious but sometimes cause pain.
Who cannot take the POP?
Most women can take the POP. Your doctor or family planning nurse will discuss any current and past illnesses. Some illnesses may mean that there is an increased risk with taking the POP. In particular, tell the doctor or nurse if you have a history of heart disease, liver disease, cancer, ovarian cysts, unexplained vaginal bleeding, or ectopic pregnancy.
How do I take the POP?
Start taking the pill on the first day of your next period. It is immediately effective from then on. If you start on any other day, you should use additional contraceptive methods (such as condoms) for the first 2 days until the POP has become effective. If you have just had a baby the POP is immediately effective if you start taking it before day 21 after the birth. There are different brands of POP. A doctor or nurse will prescribe one.
You should take the POP at the same time of day, every day. Any time of day will do, but the most important thing is to get into a routine. Do not stop taking it when you have a period. You should take it every day. When you finish one pack, start another the next day. If you take a pill more than 3 hours later than usual (12 hours for a POP called Cerazette), you lose protection (see below).
What if I forget to take a pill?
If you forget a pill, take it as soon as you remember. If you are more than 3 hours late in taking it (12 hours for a POP called Cerazette) then your protection immediately fails. Continue taking your pill each day, but you will need to use extra contraception for 2 days (such as condoms) until the POP becomes effectiver again.
What if I am ill with vomiting or diarrhoea?
If you vomit within 3 hours of taking your POP, or have severe diarrhoea, the pill will not be absorbed. Carry on taking the POP as usual, but you will need to use other forms of contraception (such as condoms) for the duration of the illness plus a further 7 days after the vomiting or diarrhoea have stopped.
Do other medicines interfere with the POP?
Some medicines may interfere with the POP and make it less effective. Tell the doctor or pharmacist that you take the POP if you are prescribed or buy another medicine.
Further information
Your GP, practice nurse, and pharmacist are good sources of information if you have any queries.
The fpa (formerly the family planning association) also provide information and advice.
fpa's Helpline: 0845 310 1334 or visit their website
www.fpa.org.uk
©EMIS and PIP 2004
