Product Summary
Combined oral contraceptives like Mercilon work by over-riding the normal menstrual cycle. In a woman's normal menstrual cycle, levels of the sex hormones change throughout each month. The hormones cause an egg to be released from the ovaries (ovulation) and prepare the lining of the womb for a possible pregnancy. At the end of each cycle, if the egg has not been fertilised the levels of the hormones fall, causing the womb lining to be shed as a monthly period.
The daily dose of hormones taken in the pill work mainly by tricking your body into thinking that ovulation has already happened. This prevents an egg from ripening and being released from the ovaries each month.
The hormones also increase the thickness of the natural mucus at the neck of the womb, which makes it more difficult for sperm to cross from the vagina into the womb and reach an egg. They also change the quality of the womb lining (endometrium), making it less likely that a fertilised egg can implant there.
Mercilon is a monophasic pill. This means that each tablet has the same dose of hormones in it. One tablet is taken every day for 21 days and you then have a seven day break from pill-taking. During your seven day break, the levels of the hormones in your blood drop, which results in a withdrawal bleed that is similar to your normal period. You start the next pack after the seven pill-free days are up, even if you are still bleeding.
The tablets come in a calender pack marked with days of the week to help you remember to take a pill every day for three weeks, followed by a week off. You will still be protected against pregnancy in your pill-free week, provided you took all the pills correctly, you start the next packet on time and nothing else happened that could make the pill less effective (eg sickness, diarrhoea, or taking certain other medicines - see below).
The contraceptive pill results in lighter, less painful and more regular menstrual bleeding. This means it is sometimes also prescribed for women who have problems with particularly heavy, painful or irregular periods.
Product Details

When can I start taking it?
Ideally, you should start taking this pill on day one of your menstrual cycle (the first day of your period). This will protect you from pregnancy immediately and you won't need to use any additional methods of contraception. If necessary, you can also start taking it up to day five of your cycle without needing to use additional contraception when you start. However, if you have a short menstrual cycle (with your period coming every 23 days or less), starting as late as the fifth day of your cycle may not provide you with immediate contraceptive protection. You should talk to your doctor or nurse about this and whether you need to use an additional contraceptive method for the first seven days.
You can also start taking this pill at any other time in your cycle if your doctor is reasonably sure that you are not pregnant. However, if you start taking this pill at any other time in your cycle, you won't be protected from pregnancy straight away and you will need to use additional contraception, eg condoms (or not have sex) for the first seven days of pill taking.
If you have given birth and are not breastfeeding, you can start taking this pill on day 21 after the birth. You will be protected against pregnancy immediately and do not need to use extra contraception. If you start taking it later than 21 days after giving birth, you will need to use extra contraception for the first seven days.
If you are starting this pill immediately after a miscarriage or abortion at under 24 weeks, you will protected against pregnancy immediately. If you start taking it more than seven days after the miscarriage or abortion, you should use extra contraception for the first seven days of pill taking. What do I do if I miss a pill?
You should try and take your pill at the same time every day to help you remember to take it. If you forget to take a pill, you should take it as soon as you remember (even if that means taking two pills in one day) and then continue to take your pills, one every day, as normal.
With Binovum, if you have missed ONE or TWO pills anywhere in the packet, you will still be protected against pregnancy and you don't need to use extra contraception. Take the last pill you missed as soon as you remember, then continue taking your pills as normal.
If you forget to take THREE or more pills, you won't be protected against pregnancy. You should take the last pill you missed as soon as you remember, forget the other missed ones and then continue to take your pills, one every day, as normal. You should then either not have sex, or use an extra barrier method of contraception, eg condoms, until you have taken a pill correctly for next seven days in a row. If the pills you missed were in the third week of your packet, you should skip the pill-free week and start a new packet straight away. If the pills you you missed were in the first week of your packet and you had unprotected sex in that week, or in the pill-free week before, it may be recommended that you take emergency contraception (the morning after pill). Ask for medical advice.