Pregnant women in Australia are facing an unfair two-tiered system for managing morning sickness, with financial status impacting who can access the full range of modern anti-nausea medications available, rather than simply clinical need.
A new study led by the University of Technology Sydney (UTS) found that Australia's Pharmaceutical Benefits Scheme (PBS) is failing to meet the therapeutic needs of pregnant patients, driving widespread off-label prescribing and perpetuating structural health inequities.
Nausea and vomiting in pregnancy (NVP) affects up to 80 percent of pregnant women, yet only 10 to 20 percent of women who suffer from it use conventional medications.
Lead author Dr Hannah Jackson, a recent PhD graduate from the UTS Faculty of Health, said treatment of NVP has a complex history due to the thalidomide tragedy, which has resulted in conservative pharmaceutical regulations and limited therapeutic innovation.
The study explored the significant challenges some women face when trying to treat one of pregnancy's most common conditions.
"We found that in some cases prescribers were finding alternative ways to get women the medication they need in a community-based setting, which can reduce health system costs by keeping them out of hospital," Dr Jackson said.
The historical cohort study analysed PBS dispensing records from nearly 300,000 pregnancies over a five-year period to assess how public resources for anti-nausea medications were distributed across different socioeconomic regions.
The findings show that while the PBS successfully performs its intended role of progressively providing affordable access to necessary medications, the narrow range of approved drugs for NVP can create significant disparities in treatment type and cost.
Despite lacking official approval or a specific listing for pregnancy under the PBS framework, the findings show that the drug ondansetron accounted for 54 percent of total PBS expenditure on anti-nausea medications in pregnancy.
"Because official subsidised options are so limited, doctors frequently rely on system workarounds to ensure patients on low incomes can afford necessary treatment," said Dr Jackson.
Total PBS-funded expenditure across all anti-nausea medications for pregnancy was concentrated most among disadvantaged women, with the rate of ondansetron use rising faster in low-income areas.
Co-author on the paper, Associate Professor Luke Grzeskowiak from Flinders University, said "the observed system workarounds create a kind of 'Robin Hood' scenario, where providing medicines outside of PBS restrictions is seen as an acceptable workaround, because it's helping vulnerable women get necessary treatment they would otherwise not be able to afford."
"With fewer medications subsidised on the PBS, pregnant women with lower financial capacity must rely on a narrow selection of older therapies, while those with more means can pay out-of-pocket for non-PBS medications which may be more suitable," said Associate Professor Grzeskowiak.
The authors argue that limited access to anti-nausea medications through the PBS can actually drive inequalities in medication access by seeing disadvantaged women access the limited subsidised medications, while affluent women can self-fund the full suite of guideline-recommended options.
With maternal health designated a national priority, the researchers urge policymakers to update Australia's medication funding structures by expanding the range of pregnancy relevant medications approved and subsidised under the PBS.
"Without reform, the current policy framework will continue to perpetuate socioeconomic inequalities, incentivise prescribing outside of standard regulatory safeguards, and lead to potential inefficiencies in public spending," said Dr Jackson.
"Ultimately, expanding PBS access to both new and repurposed existing medications will create a more dynamic, evidence-based health policy system that is truly responsive to pregnant women's health needs."
