Can anxiety in pregnant women be measured using the State-Trait Anxiety Inventory

Objective: to explore the stability of the State-Trait Anxiety Inventory (STAI), which was used to explain shifts in women's priorities for intrapartum care, Design: a comparative survey of women's priorities for intrapartum care, using a self-complete questionnaire at two intervals, 34 weeks gestation and 10 days postpartum. The questionnaire incorporated the full 40 item STAI. Setting: Aberdeen, Scotland. Participants: 217 women presenting at Aberdeen Maternity Hospital at 34 weeks gestation who were 'booked' for delivery within the hospital, and who lived within Aberdeen city. One hundred and thirty-six were expecting their first baby and 81 were expecting their second. Measurements: women's priorities for intrapartum care as ascertained at 34 weeks gestation and 10 days postpartum; shifts in priorities observed during this time period; and factors, such as anxiety (measured by the STAI), which could explain these shifts. Findings: regardless of parity, women had significantly lower A-Trait scores postnatally than antenatally, when compared over a relatively short time period. Differences between nulliparous and parous women were found where the time lapse, between completion of the scales, was more than 45 days. For nulliparous women significant differences in A-Trait scores were still evident in the 45-56 day interval, but not in the later interval of 57-91 days. Parous women appeared to follow the opposite trend, however the numbers were considerably smaller. Conclusion: the findings reported in this paper are derived from a study assessing women's priorities for intrapartum care. Anxiety was not a primary outcome measure in this study, but rather a factor which was measured as a possible explanation for shifts in priorities. However, the findings suggest that the STAI may not be stable around the time of delivery. In particular, the test-retest reliability of the STAI A-Trait scale appears to be quite low. Implications: the study reported here raises the need for further research in this area and cautions against the unqualified use of this tool until its performance, specifically in the context of pregnant or recently-delivered women, has been thoroughly assessed.