catastrophic, community-wide disasters (e.g., earthquakes
or terrorist attacks) also showed significant
effects on gestational age at birth or PTB. A third
small set of studies on chronic stressors, such as
household strain or homelessness, all reported significant
effects on PTB. Finally, a majority of past
investigations on neighborhood stressors such as
poverty and crime indicated significant effects on
gestational age or PTB. In comparison, studies on
daily hassles and perceived stress did not consistently
predict PTB. Thus, of the many distinguishable
forms of stress, many (but not all) contribute to the
risk of PTB.