Unfortunately, the picture is not as positive in Southern Africa as in other parts of the world. A report by Jonas et al showed about one in five South African women of reproductive age (15- to 49-years) have an unmet need (defined as women who do not want to fall pregnant but are not using contraceptive methods) for contraception.3
Among adolescent girls and young women, there is an even higher unmet need (31% among adolescent girls aged 15-to 19-years and 28% among young women aged 20- to 24-years).3
Benefits of access to contraceptives
Data published by the United Nations Population Fund, show that access to contraceptives saves lives by preventing unintended, unwanted, and unplanned pregnancies, reducing the need for abortions, which can often be unsafe and illegal, and the probability of maternal deaths due to pregnancy- and childbirth-related causes.3
In 2022, the use of contraception averted more than 141 million unintended pregnancies, 29 million unsafe abortions, and almost 150 000 maternal deaths.4
In South Africa, the unmet need for contraceptives among adolescent girls and young women contributes to teenage pregnancy rates, which are decreasing at a slower rate compared to other developing countries.3
About 16 million adolescent girls aged 15- to 19-years give birth each year, contributing to nearly 11% of all births worldwide. Many of these are the result of unintended pregnancies.3
Furthermore, an estimated 50% of births in low- and middle-income countries are among adolescent girls. Sub-Saharan Africa has the highest teenage pregnancy rate in the world.3
Teenage pregnancy is associated with poor health, educational, social, and economic outcomes. According to Jonas et al, improving contraceptive uptake is the most efficient method to prevent unintended pregnancies.3
How effective are contraceptives?
There are several contraceptives available. Their efficacy depends on perfect or typical use (see Table 1). Perfect use means that the method is used consistently and correctly every time. Typical use means the method may not always be used consistently or correctly.5,6
What is the most common contraception method?
Globally, the five most common contraceptive methods are:7
In South Africa, the five most common forms of contraceptives include:7
Studies show contraception preference depends on the age and relationship status of a woman. For example, adolescents (15- to 19-years) prefer the use of short-term methods that require less contact with providers, such as oral contraceptives and condoms, while adult women (20- to 49-years) favour long-acting reversible contraceptives (LARCs).7
Furthermore, female sterilisation was more common in older age groups than in younger age groups. Compared with partnered women, unpartnered women also more commonly use oral contraceptives and condoms, and less commonly intrauterine devices.7
Risks and benefits of COCs
Combined oral contraceptives (COCs) are the most commonly prescribed oral contraceptiveand contain both oestrogen and progestin. Progesterone is the hormone that prevents pregnancy, and the oestrogen component controls menstrual bleeding.6,8
COCs increase the risk of venous thromboembolic events (VTE), such as deep vein thrombosis and pulmonary embolism. The risk of VTE is highest in the first year of use and in women with additional risk factors, such as obesity, smoking, and >35-years.8
The absolute risk of VTE in women taking COCs is about seven to 10 per 100 000 women-years, compared to two to 10 per 100 000 women-years in women not taking COCs.8
The risk of ischaemic stroke is also slightly increased in women taking COCs, but the absolute risk is still very low. The risk of stroke in women taking COCs is about five per 100000 women-years, compared to three per 100 000 women-years in women not taking COCs.8
Clinicians who prescribe COCs should counsel women about the risks of VTE and stroke, especially for women with additional risk factors. Women at increased risk of VTE can be provided with a progestin-only, non-oestrogen-containing method of contraception, which does not increase the risk of VTE.8
Although the majority of women use oral contraceptives to prevent pregnancy, an estimated 14% use them for non-contraceptive reasons. Oral contraceptives can be used to address other health conditions, particularly menstrual-related disorders such as menstrual pain, irregular menstruation, fibroids, endometriosis-related pain, and menstrual-related migraines.Some oral contraceptives are also approved for the treatment of acne and hirsutism.6
Several studies also show oral contraceptives reduce the risk of endometrial cancer by 50% compared to non-users, the risk of ovarian cancer by 27% (the longer the duration of use, the greater the risk reduction. This effect lasts up to 20 years), and the risk of colon cancer by 18%.6
Selecting a COC
There is no clear superiority of one COC over another, so the choice of formulation often depends on patient preference. Monophasic regimens, in which each pill has the same hormone doses, are generally preferred over bi- and triphasic regimens because they are more likely to prevent breakthrough bleeding and are easier to use for extended or continuous dosing.8
In terms of oestrogen, most patients do not need a pill containing more than 35mcg per day to prevent breakthrough bleeding. However, lower doses of oestrogen may be associated with more unscheduled vaginal bleeding. Therefore, it is generally recommended to start with a monophasic preparation containing 30mcg to 35mcg of ethinyloestradiol.8
There are many different progestins available – again there is no evidence that any one progestin is superior to another. Patients may prefer a pill that they have used previously, and if no contraindications exist and the cost is acceptable to the patient, it is reasonable to prescribe it.8
Cyclic vs continuous dosing
COC can be dosed cyclically or continuously. Originally, birth control pills were dosed with 21 days of active drug and a seven-day placebo week to trigger a monthly withdrawal bleed. However, many women prefer less frequent withdrawal bleeds.8
Some women also report significant adverse effects during the placebo week, such as migraine, bloating, and pelvic pain. Extended or continuous use of COCs can help to manage or eliminate these problems.8
Extended and continuous use of COCs is associated with improved typical use efficacy. This is likely because greater overall hypothalamic-pituitary-ovarian axis suppression is achieved, which may offset lapses in user adherence.8
Overview of LARCs
The use of LARCs, such as intrauterine devices (IUDs) and subdermal implants, has increased substantially - from 6% of all contraceptive users in 2008 to 17.8% in 2016.8
The major advantage of LARC compared with other reversible contraceptive methods is that they do not require ongoing effort on the part of the patient for long-term and effective use. In addition, after the device is removed, the return of fertility is rapid.9
IUDs include copper-containing IUDs and levonorgestrel-releasing intrauterine devices (LNG-IUDs). An American study involving 9 256 women aged 14- to 45-years, who were offered their choice of contraceptive method without charge, found that 46% of participants preferred the LNG-IUD, 17% the subdermal implant, and 12% the copper IUD.9
Levonorgestrel-releasing IUDs
There are several types of LNG-IUDs available, which have a similar mechanism of action.All prevent fertilisation by causing a profound change in the amount and viscosity of cervical mucus, making it impenetrable to sperm.9
The LNG-20 IUD is approved for up to five years of use, while the LNG-18.6 IUD is approved for up to four years. The LNG-19.5 IUD and LNG-13.5 IUD are approved for up to five- and three years of use, respectively.9
All LNG-IUDs are highly effective at preventing pregnancy (see Table 1). The cumulative pregnancy rate for the LNG-20 IUD is 0.2% per year, while the cumulative pregnancy rate for the LNG-18.6 IUD is 0.5% per year. The cumulative pregnancy rates for the LNG-19.5 IUD and LNG-13.5 IUD are 0.31% and 0.33% per year, respectively.9
Although LNG-IUDs release a small amount of hormone, some women may experience hormone-related side effects, such as headaches, nausea, breast tenderness, mood changes, and ovarian cyst formation. Weight gain and acne are rarely reported with the use of the LNG-IUD.9
The LNG-IUD does not appear to have an adverse effect on bone mineral density or to increase the risk of fracture. Most women who use an LNG-IUD continue to ovulate but experience diminished menstrual bleeding because of the local effect of levonorgestrel on the endometrium.9
Subdermal implants
The contraceptive implant is inserted subdermally in the upper arm. It is a single-rod implant that contains 68mg of etonogestrel, which is released over a period of three years. Etonogestrel is a synthetic progestin that works by suppressing ovulation and thickening cervical mucus.9
The contraceptive implant is highly effective (see Table 1) and is safe for most women, with few side effects. The most common side effects include changes in menstrual bleeding patterns, weight gain, and acne.9
Complications related to implant insertion and removal are uncommon. Insertion complications can include pain, bleeding, hematoma formation, and deep or incorrect insertion. Removal complications can include breakage of the implant and inability to locate the implant.9
Fertility returns rapidly after the implant is removed. All healthcare providers who perform implant insertions and removals must receive training that is provided through the manufacturer.9
Copper IUD
The copper T380A IUD is a T-shaped device that is wrapped in copper wire. It works by preventing fertilisation through inhibition of sperm migration and viability. The copper IUD is highly effective at preventing pregnancy, with a one-year failure rate of 0.8% and a 10-year failure rate of 1.9% (see Table 1). It is approved for use for up to 10 years.9
The most common side effects of the copper IUD are heavy menstrual bleeding and pain. These side effects usually improve over time, but they can be bothersome for some women. The copper IUD does not disrupt pregnancy and is not an abortifacient.9
Overall, complications with IUDs are uncommon and include expulsion, method failure, and perforation. The expulsion rate is between 2% and 10% during the first year. Perforation is rare, occurring in 1.4 per 1 000 LNG-IUD insertions and 1.1 per 1 000 copper-IUD insertions.9
References
