Several medications and devices are now available to provide long-term contraception for women. These options offer from 1 month to 5 years of contraceptive protection, depending on which one you select.

Long-term contraceptives can only be obtained through your doctor or Family Planning Clinic. Your doctor will usually want you to attend for 2 appointments. The first is to discuss fully the advantages and disadvantages of the various methods of long-term contraception. At this time, your doctor will also ask about your general and reproductive health, and will often do a pelvic examination and a Pap smear, if you are due for one.

Selecting the most appropriate long-term contraceptive for your needs will depend on your individual preferences and circumstances — for example, when and if you plan to have a pregnancy in the future — as well as your previous and current general and reproductive health.

The second appointment will be at a time in your cycle when it is appropriate for your doctor to check that you are not pregnant and to administer the long-term contraceptive. Your doctor will also advise you how to recognise side effects of the contraceptive — and what to do about them should they occur — and tell you about any check-ups you may require during the use of the contraceptive.

Depot injection
Available under the brand names Depo-Provera or Depo-Ralovera, a depot injection for long-term contraception usually involves an injection into the muscle of your bottom to provide protection from pregnancy for 3 months. If contraception is needed beyond this time the injection is repeated every 3 months, for as long as needed.

How it works
Depo-Provera and Depo-Ralovera contain the medication medroxyprogesterone acetate (sometimes shortened to ‘MPA'). MPA is a progestogen, in other words, a substance that mimics the action of the natural hormone progesterone. MPA works by stopping the expulsion of an egg from the ovary (‘ovulation') each month. If no egg is present for fertilisation by sperm, then a pregnancy cannot occur.

Precautions and side effects
Following one or more MPA injections, a return to regular monthly periods and ovulation can be delayed for up to 18 months. For this reason, depot Depo-Provera or Depo-Ralovera are not recommended if you want to fall pregnant soon after stopping your contraceptive.

Depot MPA can result in altered bleeding such as unpredictable spotting, irregular periods, no periods or, rarely, heavier periods than usual.

Other possible side effects of depot MPA include weight gain, headaches and depression.

How effective is it?
If 1,000 women used depot MPA for one year, one or 2 would fall pregnant. This represents a more effective rate of contraception than that provided by the oral contraceptive pill.

Implant
The contraceptive implant Implanon is inserted under the skin of the inner, upper arm to provide 3 years of contraceptive protection. The implant is made of impregnated plastic and is 2 mm wide and 4 cm long — similar in shape and size to a match stick. Your doctor will remove the implant (under local anaesthetic) after it has been in place for 3 years, or at any time prior to this if the contraceptive effect is no longer required. Normal fertility returns soon after removal of the implant. To continue contraception, a new Implanon implant must be inserted at the time of removal of the previous implant.

How it works
Implanon continuously releases a progestogen hormone called etonogestrel, which prevents ovulation occurring each month. This means no egg is available for fertilisation, so pregnancy is avoided. Implanon also changes the mucus produced by the cervix, which makes it difficult for sperm to enter the uterus.

Precautions and side effects
Even though Implanon is inserted and removed using local anaesthetic, if you plan to use this contraceptive option, you need to be comfortable with the idea of having an implant placed under your skin.

Prolonged, irregular or absent periods, acne, weight gain and headache have been reported in some women using Implanon.

How effective is it?
Providing that the implant is inserted under the skin correctly, this method of contraception is highly effective, with no pregnancies having occurred in clinical trials using the implant.

Hormone-releasing intrauterine device
Mirena (also called the ‘progestogen IUD') is a small, T-shaped device made of impregnated plastic that is placed inside the uterus (womb). From here it releases a progestogen (a synthetic substance that mimics the natural hormone progesterone) to provide continuous contraceptive protection for 5 years. Mirena has a small string attached that passes out through the cervix — feeling the string high up in the vagina lets you know that the device is still in place. The device is removed by your doctor after 5 years, or earlier if contraception is no longer required. If further contraception is needed, a new Mirena device is inserted at the same time as removal of the previous IUD.

How it works
The progestogen in Mirena, levonorgestrel, acts directly on the lining of the uterus to make it thin and unreceptive to implantation of a fertilised egg. Mirena also changes the lining of the fallopian tubes and the mucus produced by the cervix to make it difficult for sperm to swim. In some women it also stops ovulation occurring.

Precautions and side effects
Cramping can occur in the few days after Mirena is inserted. The most common side effect of Mirena is a change in the pattern of your periods. This can include an increased time between periods or longer periods, but the longer that Mirena is in place, the more likely it is that periods will become fewer (further apart) or, for some women, absent altogether.

A progestogen IUD very slightly increases your risk of a pelvic infection. Although this is a rare side effect (fewer than one in 1,000 women), pelvic infections can reduce your fertility and so reduce your chance of having children in the future. Therefore, it is important to discuss these issues with your doctor.

As with other types of IUD, Mirena may not be suitable for women who have fibroids in the uterus. However, for women who normally experience very heavy periods, it can be a suitable choice. Again, your doctor will be able to discuss your suitability for a progestogen IUD.

How effective is it?
Mirena is more than 99 per cent effective.

Copper intrauterine device
A copper intrauterine device (IUD), for example, the Multiload cu375 IUD, is a small plastic device that has a stem wound with fine copper wire. It looks like a small anchor with 2 side branches. Attached to the base of the stem is a nylon string. The string hangs out from the uterus through the cervix and can be felt with the fingers high in the vagina. Checking for the string each month reassures you that the IUD is still in place. The copper IUD provides 5 years of contraceptive protection. The device is removed at 5 years, and a new copper IUD is inserted at this time to continue the contraceptive effect if required.

How it works
The copper IUD releases very small amounts of copper (about one-hundredth of your average food intake of copper) which create conditions inside the uterus that are unsuitable for the movement of sperm and eggs, and for the implantation of a fertilised egg.

Precautions and side effects
The presence of a copper IUD slightly increases your risk of a pelvic infection. Pelvic infections can reduce your fertility, which can reduce your chance of having children in the future. It is important to discuss these issues with your doctor.

The copper IUD can cause cramping and pain in the few days after it is inserted.

Periods can be heavier and longer than previously, when a copper IUD is in place.

How effective is it?
The copper IUD is 95 to 98 per cent effective (the contraceptive pill is about 96 per cent effective).

Vaginal ring
Not yet available in Australia, the vaginal ring is a thin plastic ring that you place high up in the vagina from where it continuously releases a low dose of an oestrogen and a progestogen. You leave the ring in place for 3 weeks, remove it, then replace it with a new ring one week later. Usually you will have a withdrawal bleed during the week between removing the ring and replacing it with a new one.

How it works
The vaginal ring contains the same type of ingredients that are used in the combined oral contraceptive pill, and it works in the same way — by stopping an egg being released from the ovaries each month, and also by thickening the cervical mucus, making it difficult for sperm to pass into the uterus. It also changes the lining of the uterus, making it more difficult for a fertilised egg to implant.

Precautions and side effects
Women who are advised against taking combined oral contraceptives, for example, because of high blood pressure or a previous blood clot, should not use the vaginal ring.

When it's available in Australia, your doctor will be able to discuss whether the vaginal ring is a suitable contraceptive option for you.

Side effects are similar to those experienced with the combined oral contraceptive pill.

How effective is it?
In studies of the effectiveness of the vaginal ring before its overseas release it was found to be 98 to 99 per cent effective in preventing pregnancy.