Posttraumatic stress disorder (PTSD) is relatively common among pregnant and postpartum women. The lifetime prevalence of PTSD for women is about 10%. PTSD is most prevalent among women of childbearing age and PTSD symptoms are common during pregnancy. Earlier this year, we reported on a study which observed that women with a diagnosis of PTSD had an increased risk of preterm birth. The risk was particularly high in those women with diagnoses of both PTSD and a major depressive episode; these women had a 4-fold increased risk of preterm birth.
A recent study has examined the relationship between PTSD and risk of preterm birth in a group of women followed by the Veterans Health Administration. In this retrospective study of 16,334 deliveries between 2000 and 2012, the researchers identified women with PTSD. They separated this group of women into those with a diagnosis of PTSD present during the year prior to delivery (active PTSD) and a group of women only with earlier diagnosis of PTSD (historical PTSD). In the Veterans Health Administration system, there is mandatory PTSD screening, using a validated instrument, is built into the electronic medical record.
Of 16,334 births, 3,049 (19%) were to mothers with a PTSD diagnosis; 1,921 (12%) of the women had active PTSD. Spontaneous preterm delivery was more common in women with active PTSD (9.2%, n=176) than in women with historical PTSD (8.0%, n=90) or no PTSD (7.4%, n=982). After adjusting for possible confounding factors, the association between PTSD and preterm birth persisted only in those with active PTSD (adjusted OR 1.35, 95% confidence interval [CI] 1.14-1.61).
This study demonstrates a statistically significant risk of preterm birth among women with active PTSD. This 35% increase in risk is similar in magnitude to what is observed with other risk factors, such as advanced maternal age. The strength of this study is its size, making it the largest to date exploring the link between PTSD and risk for preterm birth.
One question is whether we can generalize these findings to non-veteran populations of women. In this study, nearly one third of the deliveries (4,948) were to women with recent deployment (Afghanistan or Iraq) and 3,568 (23%) deliveries were to women reporting a history of military sexual trauma. The authors note that while the population studied here is distinct from women in the general population, military women experience a diverse set of traumas; however, the most common antecedent of PTSD in military women is sexual trauma, which is exactly what is observed in women in the general population.
Ruta Nonacs, MD PhD
Shaw JG, Asch SM, Kimerling R, et al. Posttraumatic Stress Disorder and Risk of Spontaneous Preterm Birth. Obstet Gynecol 2014.