03.Short term contraception
There have also been advances in more short-term contraception, with an injectable contraceptive, a large variety of pills and a female condom all on the market. These methods, however, rely more on the individual, and thus tend to suffer from lower efficacy rates.
Name: Depot medroxyprogesterone acetate injection, marketed in Australia as Depo-Provera or the generic Depo-Ralovera.
Method: A synthetic hormone similar to progesterone is injected by a doctor or nurse every 12 weeks.
Price: Each injection costs about $26-$30, depending on brand.
Use: It is injected into the buttock or upper arm of a woman, and takes seven days to become effective. It is not immediately reversible, and women can take up to two years to return to full fertility.
Efficacy: 94% with typical use, 99.8% with perfect use.
For women under the age of 18 or over 45, the contraceptive injection is not a first choice due to certain side effects. However, Bateson says it can be a useful option for some women. “The injection does have an effect on bone density. But for women in their mid-reproductive years, that reduction in bone density is easily reversible once they stop having the injection. One advantage for some women is after using the injection for one year, 50% of women have no bleeding, and that percentage increases over time.”
Name: Contraceptive hormone vaginal ring, marketed in Australia as NuvaRing.
Method: A soft, plastic ring is inserted by a woman into her vagina. Once inserted, it releases low doses of oestrogen and a progestogen, the same hormones as in the combined oral contraceptive.
Price: About $25 per ring.
Use: Once inserted, the ring remains in place for three weeks, and must then be replaced, either in one week after a withdrawal bleed, or immediately to avoid menstruation. The ring is prescribed by a GP.
Efficacy: 91% with typical use, 99.7% with perfect use.
“It’s an alternative delivery system to the pill,” says Bateson. “The benefit is you don’t have to remember to take a pill every day. It appears to be relatively beneficial for cycle control, and it’s good for women who have breakthrough bleeding with the pill. However, the downside is it’s not on the PBS so cost may be an issue.”
Another advantage of the NuvaRing is that unlike with the pill, vomiting and diarrhoea does not reduce its effectiveness as the hormones aren't absorbed in the intestinal tract.
Name: Combined and progestegen-only (mini) oral contraceptive pills, marketed under various brand names in Australia.
Method: Most combined pill packs contain 21 active pills and seven inactive placebo pills, which allow women to menstruate. Each mini pill pack contains 28 active pills. There is leeway of up to 24 hours if a combination pill is missed, or just three for a progesterone-only pill, after which time a woman may no longer be protected against pregnancy.
Price: From about $35 to $283 for a year’s supply.
Efficacy: 91% with typical use, 99.7% with perfect use.
The contraceptive pill is the most common form of contraception used in Australia. “We’ve got a lot of data on [the pill]”, says Bateson. “It can be useful for controlling acne, managing heavy periods and decreasing period pain. Sometimes the pill can control headaches that some women get with their periods.”
One of the main benefits of the combined contraceptive pill is the ability it gives women to control their menstrual cycle by skipping the placebo pills. “We now have plenty of data to show that it’s safe to have continuous pill use for up to one year. Some women will get breakthrough bleeding with prolonged use, so we sometimes advise three-month cycling.”
Gastric upsets and certain medication can impact on the effectiveness of the pill, as can human error.
Emergency contraception is now available over the counter – useful in cases when contraception is forgotten or may have failed. Unfortunately, many women may not be aware of this option. “While almost all Australian women in a recent survey had heard of the emergency contraceptive pill, fewer than half were aware it is available without a prescription at the pharmacy,” says Bateson.
The most common emergency contraceptive method is a single 1.5mg dose of levonorgestrel taken within three days of unprotected intercourse. It can be used up to five days after, but its effectiveness may be reduced.
“The emergency contraceptive pill is safe and there are no contra-indications as a result of taking it,” says Mazza.
Copper IUDs may also be used for emergency contraception up to five days after unprotected intercourse.
Aside from these newer forms of contraception, there are other options that may be suitable. The diaphragm is still favoured by some women, despite its relative lack of efficacy. With perfect use, it is 94% effective. With typical use, that figure drops to 88%.
Female condoms, which can be difficult to find, can be used by those with latex allergies and allow women to protect themselves against STIs. But at about $3 each they’re relatively expensive and their typical use efficacy rate is low, so they should be used in conjunction with more effective contraception to prevent pregnancy.
and fertility awareness
(timing of the cycle, temperature-taking) are also less effective forms of contraception. Although with perfect use their efficacy can be high, it drops significantly with typical use – just 78% for withdrawal, and 76% for fertility awareness.
Popular in the past, copper IUDs are also still available on the market. “They have a valuable place in the contraceptive arsenal for women requiring a highly effective, long-acting, hormone-free method,” says Bateson.
Goldstone says work on a hormonal male contraceptive
is ongoing. “In terms of temporary methods, most involve blocking sperm, but in the process of that they block testosterone that then needs to be replaced, and men don’t appear to be very receptive to that idea.” But there is a potential male contraceptive pill in the works.
Researchers in the US believe they have discovered a compound that may be used to make the first hormone-free contraceptive pill for men. The researchers have developed a small molecule that in mice blocks the cell division necessary for normal sperm production, says Professor Robert McLachlan, Director of Clinical Research at Prince Henry’s Institute of Medical Research. According to the researchers, the drug has no significant side effects. However, it is in early stages of development and may take 15 years to become available for human use.
In the meantime, there are male condoms. Condoms have an efficacy rate of 82% with typical use, and 98% with perfect use. Their high failure rate is mainly attributed to incorrect or non-use, or condom failure such as breakage. They provide protection from STDs, and thus for those at risk of STIs can be doubled up with another, more effective contraceptive method.