Gynaecology Contraception

Contraception, also known as birth control is a way to stop a woman becoming pregnant when she does not wish to become pregnant. Numerous methods of contraception are in practice and range from natural family planning techniques to sterilisation (male or female) and include barrier or hormonal methods.

Natural family planning methods: Natural family planning (NFP) or fertility awareness does not require medication, physical devices, or surgery to prevent pregnancy. This method relies on the woman’s body physiology to know the time of ovulation. This method involves monitoring different body changes such as basal body temperature or cervical mucus variations. The woman then abstains from unprotected sex for approximately 7 to 10 days when she may have ovulated. NFP is often referred to as the Billings Method of Contraception.

Barrier methods form a physical barrier to obstruct the sperm from entering a woman’s uterus. The most common barrier method is the male condom. Other barrier methods are available such as the contraceptive cap.

Hormonal methods: In this method synthetic hormonal preparations containing oestrogen and progesterone will be taken orally (pills), implanted into body tissue (Implanon), injected under the skin (Depo-Provera), absorbed from a patch on the skin (skin patches), or placed in the vagina (NuvaRing). These methods work by preventing ovaries from releasing an egg for fertilisation. It also thickens the mucus around the cervix, making it difficult for sperm to penetrate and also thins the lining of the womb decreasing its ability to accept a fertilised egg. The intrauterine device (IUD) is a small device made of copper or impregnated with progesterone (Mirena Coil/Jaydess IUD) that is inserted into the uterus. It works by thickening the mucus around the cervix and by thinning the womb’s lining, making it difficult to accept a fertilised egg.

Tubal Ligation or Vasectomy: These methods are a permanent method of contraception  for men or women who do not intend to have children in the future. Male sterilisation called a vasectomy is a surgical procedure performed under local or general anaesthetic on the testis when the ducts connecting the site of sperm production in the testicles  vas deferens are tied. Female sterilisation his a surgical procedure to block or remove the fallopian tubes thus preventing sperm and eggs meeting to fertilise. It is either performed at the same time as a caesarean section or separately under a general anaesthetic during a laparoscopy.

The choice of a particular method of contraceptive also depends on a womans age, whether she has started or even finished having her family and certain medical conditions. Therefore always discuss with your own doctor or Dr McMurray about the choice of birth control method.

The Mirena Coil

What is the Mirena Coil?

The intrauterine system (IUS) is a very effective method of contraception. It is also used to treat heavy periods (menorrhagia). Each device works for five years.

What is the intrauterine system?

The IUS is a small, plastic, T-shaped device. There are threads attached which will lie in your vagina. These allow you to check it is still there. They also mean it can be removed easily. It is put into a woman’s womb (uterus) by a doctor. It looks like an intrauterine contraceptive device (IUCD) – also known as the contraceptive coil. It also contains progestogen hormone, so it is called an intrauterine ‘system’ (IUS) and not an IUCD.

How does the intrauterine system work as a contraceptive?

It works differently to a coil because of the progestogen hormone. The hormone thickens your mucus. This forms a plug in the cervix. This stops sperm getting through to the womb to fertilise an egg. The hormone also makes the lining of your womb thinner and this may have beneficial effects on a woman’s period.

How effective is the intrauterine system for contraception?

It is very effective. Around 2 women in 1000 using the IUS will become pregnant each year. Which is comparable to the pregnancy rate in women who have been sterilised.

What are the advantages of the intrauterine system?

Once it is inserted you can forget about contraception for five years. It does not interfere with sex. Periods usually get lighter, less painful and often stop (unlike the copper coil). After 12 months most users might only have a light bleed for a couple of days per month, and about 1 in 5 users have no bleeding at all. Fertility returns as soon as it is removed. The IUS may also be used as a treatment for heavy periods, endometriosis and fibroids.

What are the disadvantages of the intrauterine system?

Although the majority of women with an IUS have no problems, the following may occasionally occur:

You may have irregular bleeding for the first three to six months. This usually settles down. It is usually a light ‘spotting’ of blood which women can find a nuisance. The IUS may come out without you noticing (expulsion). This happens to 1 woman in every 20. It usually happens in the first three months during your period. Fitting an IUS can very rarely cause damage to the womb. In less than 1 woman in every 1,000 the IUS may go through the wall of the womb (perforation).

Are there any side-effects?

Side-effects are uncommon. The progestogen hormone released by the IUS mainly effects the uterus and limited effects in other parts of the body. So side-effects are less common than with the progestogen-only contraceptive pill and the contraceptive injection or implant. If side-effects do occur, they tend to develop in the first 3-6 months and then tend to ease and go. Examples of possible side-effects include: mood swings, reduced sex drive, fluid retention and increase in acne and breast discomfort. There is limited evidence that women with an IUS put on weight.

Who cannot use the intrauterine contraceptive system?

Your doctor or family planning nurse will discuss your medical history. Some illnesses may mean you cannot use progestogen-based contraceptives, such as the IUS. These include recent (in the preceding five years) breast cancer, very large fibroids or an infection which has not been treated. In practice, the number of women who cannot have the IUS inserted is small.

How is the intrauterine system fitted?

This is usually done towards the end of your period, or just afterwards. However, it can be fitted at any time provided that you are certain you are not pregnant. You will need to have a vaginal examination. The doctor will pass a small instrument into your womb to check its size and position.

The device is then directed through your cervix and into your womb.

You will be taught how to feel the threads so you can check it is in place. It is best to check the threads regularly – for example, once a month just after a period.

If it is fitted within seven days after the start of a period, it is immediately effective as a contraceptive. If it is fitted after the 7th day then you need to use extra protection such as condoms for seven days.

The procedure can be uncomfortable. Just after the device is fitted some women have crampy pains like period pains for a few hours. These can be eased by painkillers such as paracetamol or ibuprofen. Light vaginal bleeding may also occur for a short while.

For some women it may be necessary to insert the Mirena coil under a local/general anaesthetic, please contact Clare if you wish to discuss this option further.


The doctor will usually want to check that there are no problems after your first period. After this, there is no need for any routine check until it is time to remove the IUS.

Most women have no problems and the IUS can remain in place for five years. It needs to be replaced after five years if you wish to continue with an IUS. It can be removed at any time by a trained doctor or nurse.

Your fertility will return to normal as soon as the mirena is removed. If you plan to have it removed, but do not want to get pregnant, then use other methods of contraception (such as condoms) from seven days before it is removed. This is because sperm can last up to seven days after having sex.

You can still use sanitary towels or tampons when an IUS is in place. You should consult a doctor if any of the following occur:

  • Prolonged abdominal pain after an IUS is inserted.
  • Vaginal discharge with or without pain.

This may indicate infection. If you suspect that the IUS has come out or is coming out. It is usually possible to feel the threads of the IUS inside your vagina. If you cannot feel the threads then use other contraception (such as condoms or not having have sex) until you have been checked by your doctor. The coil threads may have moved out of site and touch within the cervix. An ultrasound may need to be arranged to confirm the coil is still within the womb.