MIRENA - THE INTRAUTERINE SYSTEM (IUS)
WHAT IS IT?
The Mirena, hormonal intrauterine system is effective long term and reversible method of contraception. It is also used to treat heavy periods. It consists of a small, plastic T shaped frame which is inserted by a trained doctor into the womb. Mirena slowly released the hormone substance levonorgestrel. The system remains effective for 5 years but may be removed at any time.
HOW DOES MIRENA WORK?
Mirena works in a number of ways.
1. It thickens the mucus in your cervix, so it helps to stop sperm reaching the egg.
2. It inhibits normal sperm function inside the womb and the ovarian tubes
3. It make the lining of your womb thin, making periods lighter and shorter.
HOW EFFECTIVE (RELIABLE) IS IT?
Mirena is a highly reliable method of contraception. Studies show that if 1000 women use the system for 1 year no more than 2 will become pregnant. This is as effective as female sterilisation.
WHAT ARE THE ADVANTAGES OF MIRENA?
1. It is highly effective.
2. It works as soon as it is fitted.
3. It works as a long term contraceptive yet it is reversible.
4. It offers the convenience of “fit and forget” it.
5. After you have used Mirena for about three months you periods become lighter and shorter.
HOW IS MIRENA FITTED?
Usually only a specially trained doctor fits the system. It is done preferably between day 3 to 7 of your menstural cycle. Your doctor will give you a pelvic examination to find out the position and size of your womb before the pelvis is fitted. Most women find the that fitting caused only a little discomfort. Some women may wish to discuss the need for a pain killer with their doctor prior to insertion. Ponstan (Mefenamic acid) 500mg 1 hour before the consultation is usually well worth taking. Afterwards you might feel some cramping, like a period pain, which usually responds to more Ponstan. Preparation for fitting usually takes about 5 minutes and the actual fitting of the system only takes a few seconds.
CAN ANYONE USE AN IUS?
Most women who want to use an IUS can do so, including women who have never been pregnant and women who are HIV positive. Some of the conditions which mean that you may not use an IUS are:
· if you think that you may already be pregnant
· if you have now or had in the past, cancer of the womb or breast.
· active liver disease
· unexplained bleeding from your vagina eg. between periods or after sex
· heart attack or stroke (severe arterial disease or thrombosis)
· blood clots
· an untreated sexually transmitted infection or pelvic infection
· problems with the cervix or womb.
WHAT HAPPENS TO PERIODS?
Mirena does effect your menstrual cycle. Many women have spotting ( a small amount of blood loss or light bleeding in addition to their periods) for the first 3 to 6 months after the system is fitted.
Overall you are likely to find that after the first few months your periods will become much lighter than usual. Some women find that their periods stop altogether. All women notice a significant decrease in the amount of bleeding plus a reduction in the amount of days that their periods last.
ISN’T IT ABNORMAL NOT TO HAVE PERIODS?
Not if you are using Mirena. If you find that you do not have periods with Mirena it is due to the effect of the hormone on the lining of the womb. Essentially the hormone in the Mirena puts the lining of the womb into neutral. The monthly thickening of the lining of the womb with blood does not happen, therefore there is no blood to come away as a period but this does not mean that anything is blocked. Essentially it is not built up so the blood cannot come away. Your own hormone levels remain the same and you will find that your periods return to normal when the Mirena is removed. Not having periods and a reduced blood loss can be a great advantage to women’s health.
WHAT ABOUT HEAVY PERIODS?
Studies have shown that the Mirena is highly effective in treating heavy periods. Many women who now have been treated with Mirena, would in previous times have had their wombs removed.
WILL I PUT ON WEIGHT?
Studies have shown that women using Mirena have not changed their weight any more than women not using it.
WHAT ABOUT SIDE EFFECTS?
Well the level of hormone in the woman’s blood stream is very low so that the side effects such as breast tenderness, headaches or acne are rare. If they do occur they usually disappear after the first few months.