Intrauterine devices (IUDs) or contraceptive coils are a popular long-acting reversible contraception (LARC) method. As a primary care practitioner, it is important to be able to counsel women regarding the indications, contraindications, risks and benefits, insertion procedure, and potential side effects of IUDs.
Learn more about this topic in the HealthCert Advanced Workshop of Intrauterine Systems.
IUDs are categorised into two types – the copper IUD and the hormonal IUD (sometimes known as the intrauterine system or IUS).
Copper IUDs available in Australia last for either 5 or 10 years, and their primary mechanism of action of a copper IUD is reducing sperm motility, preventing fertilisation, and rendering the endometrium inhospitable for pregnancy.
The hormonal IUD (e.g., Mirena or Kyleena) is effective for 5 or 6 years and releases a progestogen hormone (levonorgestrel). This hormone causes thickening of the cervical mucus, hindering sperm entry to the uterus, changes in the endometrium, rendering it unable to support implantation of pregnancy; and, in some women, prevents ovulation.
IUDs are suitable for most women of childbearing age and are particularly indicated in women not planning a pregnancy soon. Contraindications are few and include current pelvic infection, unexplained vaginal bleeding, certain cancers, and some uterine abnormalities (e.g., large fibroids). Contraceptive coils are user-independent and, therefore, highly effective, preventing pregnancy in over 99% of users.
The primary advantage of the copper coil is that it does not contain hormones and is, therefore, suitable for women who wish to avoid hormonal contraception. It will not affect the frequency of the natural menstrual cycle; however, it is important to counsel women on the potential side effects of longer, heavier, and more painful periods.
The hormonal IUD releases progestogen and may not be suitable for women in whom exogenous hormones are contraindicated (e.g., breast cancer). The most common side effect of the hormonal coil is changes to the natural bleeding pattern; it is important to discuss this. Users of the hormonal coil may experience irregular menses, unpredictable spotting, or may become amenorrhoeic. As the hormonal coil affects the endometrium, it is often used for its non-contraceptive benefit of reducing menstrual blood loss in conditions such as menorrhagia and dysmenorrhoea. Other side effects of the hormonal coil include breast tenderness, fluctuations in mood, and skin changes.
In terms of insertion, an IUD is inserted by a trained practitioner and involves a bimanual examination to determine the size and orientation of the uterus, followed by a speculum examination to visualise the cervix. A sound is passed through the cervix to measure the fundal height, and the coil is inserted to the measured depth. The insertion procedure typically takes around 10 minutes and may be accompanied by discomfort, for which anaesthesia should be offered.
The copper coil can also be used as emergency contraception, where it is typically inserted within five days of unprotected intercourse.
It is important to counsel patients on the risks of having an IUD, including perforation, expulsion, infection, and contraceptive failure. Following coil insertion, patients may have abdominal discomfort, bleeding, or side effects from the coil itself.
When a woman presents to a general practitioner with problems related to a contraceptive coil, it is important to rule out pregnancy, perform a speculum examination to confirm the presence of the coil threads and conduct a bimanual examination to assess for any signs of pelvic inflammatory disease (PID).
In conclusion, IUDs are a popular and effective method of long-acting reversible contraception that should be discussed as an option in women of childbearing age seeking contraception. As a primary care practitioner, it is important to be able to counsel women regarding the indications, contraindications, risks and benefits, insertion procedure and potential side effects.
Dr Samantha Miller, MBChB
Learn more about this topic in the HealthCert Advanced Workshop of Intrauterine Systems.
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