HIV Insight: Use of Prescription Medicines in Australian Women of Child-Bearing Age

Background

This study aimed to examine current utilisation of prescribed medicines amongst Australian women of child-bearing age, with a particular focus on the extent of use of medicines in Category D and X risk groups, which are moderate and high risk teratogens, respectively. The use of those medicines may pose risk of birth defects in pregnant women.

Methods

A retrospective cross-sectional study was undertaken involving all women of child-bearing age (15 to 44 years) who were dispensed medicines in 2013 using the 10 % random sample of dispensing data from the Australian Government Department of Human Services. Dispensing patterns were reported by medicine, therapeutic class, pregnancy risk category and women’s age.

Results

Over one-third of women aged 15 to 44 years received at least one prescribed medicine in 2013. Psychoanaleptics, antibiotics and analgesics were the top three classes. Around 9 % of all dispensings were for medicines from risk category D, with statins, agents acting on renin-angiotensin system, and some anti-epileptic agents being the most commonly used. Both statins and agents acting on renin-angiotensin system showed increasing use with age, estimated to be 35,600 women nationally for each group. Collectively between 2 % and 4 % of women used anti-epileptics from risk category D in each year of age, with overall use estimated to be 51,000 women nationally. Below 1 % of all dispensings were for category X medicines, mainly isotretinoin.

Conclusions

It is important for medical practitioners to offer counselling around pregnancy planning and the risk of birth defects when prescribing moderate or high risk teratogens to women in child-bearing age. For the antihypertensives and some anti-epileptics, alternative medicines with lower risk categorization are available.

Below: Birth rate and rate of unique women dispensed at least one PBS subsidised medicine in 2013 as proportion of estimated female resident population at 30 June 2013 (by age)

Below: Top 15 therapeutic classes (by ATC category, level 2), ordered by percentage of all dispensings in 2013; presented by pregnancy risk category (visualize pregnancy category proportions > =2 % within a class)

Below: Use of selected medicines from category C, D and X which may pose increased risk of birth defects (by age). Legend: ^ Category C; * Category D; ** Category X; ACE inhibitors – Angiotensin converting enzyme inhibitors; ARBs – angiotensin II receptor antagonists. SSRIs – Selective serotonin reuptake inhibitors