Perinatal Depressive Symptoms: A Search for a Biologic Marker

The relationships among biological factors, psychological status, health behaviors, life stress, neuroendocrine mechanisms, and perinatal depressive symptoms were examined in two secondary analyses. The first secondary analysis examined postpartum depressive symptoms with data originating from 113 postpartum low-income mothers with low birth weight infants in the Neonatal Intensive Care Unit (NICU). Maternal demographics, medical history, and self-administered psychological instruments were obtained from the parent study. A sub-sample of 9 women also provided four saliva and blood samples for the measurement of cortisol (saliva) and oxytocin (plasma). Increased postpartum depressive symptoms were related to lower infant birth weight, more severe infant illness, increased posttraumatic stress symptoms, increased anxiety, and increased parental stress. In the sub-sample, cortisol had a dysregulated 24-hour pattern, while oxytocin was inversely related to posttraumatic stress symptoms and anxiety. Though much is known about the adverse outcomes of elevated postpartum depressive symptoms, little is known about the relationship among posttraumatic stress, postpartum depressive symptoms, and neuroendocrine mechanisms. Future research should include assessment of posttraumatic stress, anxiety, and neuroendocrine mechanisms for mothers at risk for elevated postpartum depressive symptoms including those who deliver premature infants. The second secondary analysis examined the relationships among contributing factors, oxytocin, and prenatal depressive symptoms. In this secondary analysis, data from 57 pregnant African American women residing in an urban setting were analyzed. Maternal demographic information, a medical history review, self-administered psychological instruments, and plasma oxytocin levels were obtained at two time points during pregnancy, 15 – 22 weeks gestation and 25 – 37 weeks gestation, with an additional medical record review after birth. Oxytocin was inversely related to prenatal depressive symptoms and infant birth weight. Previous obstetrical complications, increased maternal age, and smoking were related to a decrease in oxytocin between the second and third trimester of pregnancy. Women with less family support, a current obstetrical complication, and a previous medical diagnosis were at risk for elevated prenatal depressive symptoms. Although the data suggest that oxytocin may be a potential biomarker to help identify women at risk for prenatal depressive symptoms, future research is warranted to confirm these results