Asthma is one of the most prevalent long-term health conditions affecting pregnant women. Poorly controlled asthma during pregnancy is associated with adverse maternal and fetal outcomes and may predispose offspring to long-term respiratory morbidity. The current ‘one size fits all’ approach to asthma management during pregnancy is not optimally effective for approximately half of the pregnant women with asthma. A personalised medicine approach to managing airways disease is required. The treatable traits approach focuses on the identification and treatment of traits in the pulmonary, extra-pulmonary and behavioural domains, which are identifiable, measurable, clinically relevant (linked to exacerbation risk or poor asthma control) and treatable. This manuscript outlines the protocol for the Treatable Traits for Asthma Management in Pregnancy (TTAP) study. The purpose of the TTAP study is to prospectively determine the prevalence of a range of treatable traits from these three domains in pregnant women with asthma and determine which traits are associated with exacerbation risk, poor asthma control and poor asthma-related quality of life. Additionally, this study will assess differences in trait prevalence and clinical relevance in pregnant women from regional versus metropolitan hospitals in Australia and in different antenatal models of care.

The TTAP study is a multicentre, prospective observational cohort study. Study participants are pregnant women with asthma attending antenatal clinics at 10 metropolitan and regional hospitals (public and private) in NSW and Victoria, Australia. Assessment of traits from the pulmonary, extrapulmonary and behavioural domains as well as asthma outcomes is conducted at three gestational timepoints: 12–16 weeks, 22–26 weeks and 32–36 weeks of pregnancy. A follow-up assessment of asthma outcomes is conducted at 2–4 weeks postpartum. The outcomes assessed are asthma exacerbations requiring medical intervention (primary outcome), asthma symptom control and asthma-related quality of life. Traits and outcomes will be assessed using questionnaires, direct questioning, measurement of biomarkers, physical measurements and assessment of routinely collected data from medical records.

The Hunter New England Human Ethics Committee (2024/ETH01289) has approved the TTAP study protocol. Outcomes will be published in peer-reviewed journals, presented at scientific conferences and disseminated online to participants, clinicians and other pregnant women with asthma and their families via the Asthma in Pregnancy Toolkit website https://asthmapregnancytoolkit.org.au/.