The intrauterine device (IUD) is a safe and effective method of reversible contraception. IUDs are small flexible
devices made of metal and/or plastic; they may be inert, or may release copper or hormone.
Duration of use
The TCu 380A has proved to be highly effective for at least 12 years with a cumulative pregnancy rate of 2.2 per
100 women, while the TCu 220C is also effective for this length of time, but to a lesser degree. The ML Cu 375
is effective for at least 10 years. The Nova T200 is
recommended for up to 3 years of use, after which failure rates increase substantially. The Nova T380 is
effective for 5 years, with a cumulative pregnancy rate of 2.0. The levonorgestrel-releasing IUD lasts for more
than 5 years with a cumulative pregnancy rate at 5 years of 03.-1.1 per 100 women.
Mode of action
Any IUD prevents pregnancy by a combination of mechanisms of action, including:
• Inhibition of sperm migration in the upper female genital tract.
• Inhibition of ovum transport.
• Inhibition of fertilization.
The levonorgestrel-releasing IUD, in addition to the above, causes changes in the amount and viscosity of the
cervical mucus, inhibiting sperm penetration.
• Cramping pain may occur for the first 24 to 48 hours after insertion of the device. If the woman experiences
this, she can take pain-relief tablets such as aspirin, ibuprofen or paracetamol (acetaminophen). If the pain
does not improve or becomes severe, she should visit the clinic. (Pain does not usually occur after 48 hours).
• Vaginal discharge may occur during the first few weeks due to the initial reaction of the lining of the uterus
(endometrium). This should not be a cause for concern, but if the discharge is heavy, or accompanied by pelvic
pain and/or fever, the woman should contact the clinic immediately.
• Changes in menstrual periods – including spotting or light bleeding between periods – are common during
the first 3-6 months of use of a copper-bearing IUD. These are not harmful and usually improve over time. The
client may be advised to take a short course of non-steroidal anti-inflammatory drugs during the bleeding days.
If the changes persist or if her periods are more than twice as heavy as normal, underlying gynecological
problems should be excluded. If the client finds the changes unacceptable, remove the IUD and help her to
choose another method of contraception.