The purpose of this quasi-experimental pretest-posttest study was to test whether regularly spending time in the natural environment would improve concentration for women in the third trimester of pregnancy, a time when women rely on their ability to concentrate in order to prepare for birth and parenting. Several measures requiring concentration were administered before an intervention that included spending 120 minutes each week in restorative activities involving nature. When posttest measures were collected women in the intervention group had signficantly fewer errors compared to the control group. Other measures did not reveal significant differences. These results suggest that encouraging women to spend time in activities that involve nature and designing health care environments to incorporate nature may help pregnant women improve their ability to concentrate and reduce errors at a time when they have many demands on their time and attention.