To our knowledge, no randomized trial has shown that a universal program providing psychosocial support and education, delivered prenatally, can prevent ABOs. In this report, we test the effect on ABOs of a group-format program designed to prepare couples to enter parenthood together in a supportive manner. Family Foundations (FF)—consisting of a series of classes for first-time, expectant couples—has been shown to reduce maternal stress and depression measured at 6 months after birth [29]. We reason that, as half of the eight FF classes took place before birth (the remaining classes took place 3–6 months after birth), the program’s impact on maternal stress and depression may have begun during pregnancy. Thus, we hypothesize that the program’s impact in reducing maternal negative emotional states reduces risk of ABOs.
We also assess evidence of risk moderation. In this case, we hypothesize that FF offers relatively greater beneficial impact for women at higher risk for ABOs due to elevated cortisol during pregnancy. The hypothalamic–pituitary–adrenal (HPA) axis is linked to stress, depression, and physical health problems [32]. Cortisol levels in saliva—an indicator of HPA activity–rise to a plateau during pregnancy; near the end of pregnancy [33, 34], cortisol levels rise and likely play a role in triggering labor [35]. Thus, women with higher levels of cortisol are more likely to enter labor at shorter gestational ages and have low birth weight babies [36–39].
We test the impact of FF as a protective factor, buffering the negative impact of high cortisol levels. Because we did not measure women’s stress and depression before childbirth (apart from the pre-intervention assessment), we are not able to test whether it is in fact the program’s impact on maternal psychological well-being that is responsible for detectable improvement in birth outcomes. However, evidence of buffering ABOs would be consistent with our expectation that the program’s impact on stress and depression began during the prenatal portion of the program. Findings of program impact in this study would support further development and testing of interventions that promote maternal mental health— especially interventions that enhance the supportiveness and overall quality of primary relationships, particularly the coparenting relationship.