Introduction:
Research findings suggest that prenatal posttraumatic stress disorder (PTSD) is associated with poor maternal mental health, and disrupted mother-infant bonding. In addition, a number of studies suggest that prenatal PTSD may also be associated with adverse neonatal outcomes, but this remains unclear. The aim of the present narrative review was to synthesize the available evidence from observational studies on the relationship between prenatal PTSD and preterm birth (PTB).

Material and Methods:
Using a set of search criteria, the Scopus and PubMed databases were reviewed. No limitations on the date of publication or geographic location were placed on the inclusion of observational studies that were peer-reviewed and published in the English language.

Results:
The database search revealed eight cohort studies and almost all of them were from the United States. The number of participants in the studies ranged from 285 to 9930, and the sample size for those with PTSD included 2155 women. The majority of the studies (n=6) found that women who reported PTSD had higher odds of having a PTB compared to women without antenatal PTSD. Three studies did not find a statistically significant association between maternal PTSD and PTB.

Conclusions:
Findings suggest that prenatal PTSD may be associated with an increased risk of preterm birth. This information might lead to midwives screening for PTSD more vigorously throughout the perinatal period.