December 2019 Health Bulletin

What hormonal contraceptives are Australian women using?

Hormonal contraceptives are used not only for fertility control but also for cycle control, management of acne, hirsutism, and premenstrual and menstrual symptoms. As many hormonal contraceptives are on private prescription rather than on the Pharmaceutical Benefits Scheme, specific formulations used by Australian women have not previously been quantified.

The Grollo Ruzzene Foundation Young Women’s Health Study recruited women aged 18-39 years living in Victoria, New South Wales and Queensland from November 2016 till July 2017. They were asked to complete an online questionnaire which included extensive socio-demographic and health information. Women were asked to indicate which hormonal contraceptive they had used in the past 4 weeks from a list which included all oral contraceptives, and long acting reversible contraception (LARCs) – implants, injectables and the intrauterine system.

In this group of women approximately 43% were currently using hormonal contraception with most (63%) using a combined oral contraceptive pill (COC). About one-third of these were taking a COC not subsidised by the PBS, most of which (95%) contained an anti-androgen preferentially prescribed for acne and hirsutism. These COCs containing a third or fourth generation progestin are more expensive, which creates a cost burden for women in whom this treatment is the best option.

LARCs/injectables accounted for over one-quarter of hormonal contraceptives in this Australian study, which is higher than previously thought, and may reflect increase in acceptability and ease of insertion, and accepted first-line treatment in women with endometriosis.

A new finding was that women living in rural areas were more likely to use hormonal contraception than women living in metropolitan areas.

In line with other studies, obese women were less likely to be using hormonal or any other type of contraceptive. It may be that obese women have concerns about weight gain with the COC however, available evidence does not support this. Potential health care practitioner barriers to prescribing hormonal contraceptives in this group may relate to venous thrombosis and contraceptive failure with the use of COCs, and confidence and difficulties in inserting LARCs.

The absolute risk of venous embolism in COC users is low however, age, smoking and obesity are independent risk factors. There is also an apparent increase in risk with the use of COCs containing a third or fourth generation progestin. In this study the majority of obese smokers were appropriately prescribed a LARC/injectable, a progestin-only pill, or a COC with a second generation progestin. It is of some concern however, that some were prescribed a COC containing a third or fourth generation progestin.

This study has highlighted that access to anti-androgenic COCs, used by one third of COC users, is not equitable through the PBS and the authors suggest a triage system could be established where women with a clinical indication could have access to subsidised medication. Also, of the women who are obese and smokers, 12.1% are using COCs which have a higher risk of venous thrombosis and clinical guidelines are needed to provide recommendations for this group to minimise harm.

Skiba MA, Islam RM, Bell RJ, Davis SR. Hormonal contraceptive use in Australian women: Who is using what? Aust N Z J Obstet Gynaecol. 2019;59(5):717–724. doi:10.1111/ajo.13021

Information provided might not be relevant to a particular person's circumstances and should always be discussed with that person's own healthcare provider.