Date of Award
2024
Document Type
Dissertation
Degree Name
Doctor of Medical Science (DMSc)
Department
Department of Physician Assistant Medicine
First Advisor
Kara Roman
Second Advisor
Andrea Olmstead
Third Advisor
Jaydeen Morris
Abstract
Postpartum depression is experienced by up to 15% of mothers and can greatly impact the experience that they have with their newborns.1 Postpartum depression can be associated with young maternal age, smoking, antenatal depression, stress during pregnancy, and newborns requiring intensive care.2 It most often develops about 6 or more weeks after birth and can range from postpartum “blues” to postpartum psychosis.3 If left untreated, postpartum depression can lead to poor maternal-fetal bonding, breastfeeding failures, and worse outcomes for the psychological and physical development of the child.3 Untreated postpartum depression is also associated with extended periods of depression and increased rates of suicide.2
Oxytocin is an important hormone that is heavily involved in the birthing process. It plays a role in labor, lactation, and infant bonding. Endogenous oxytocin increases throughout pregnancy and peaks immediately following birth, supporting uterine contractions to detach the placenta and lower the risk of postpartum hemorrhage. Oxytocin is also largely involved in the breastfeeding process. It is part of a feedback loop that stimulates contraction of myoepithelial cells in mammary tissue to eject milk, otherwise known as the letdown reflex.18
Henshaw et. al investigated the role of oxytocin in breastfeeding.5 Oxytocin inhibits the hypothalamic-pituitary-adrenal axis (HPA) activity, which in most mothers, leads to a calming effect.5 There is conflicting information, but studies have shown that women who experience depressive symptoms immediately after cessation of breastfeeding correlate with low levels of plasma oxytocin. There is also evidence that disruptions in the HPA axis, estrogen, and progesterone, like in breastfeeding disruptions or latch difficulties, can impact mood and depressive symptoms.
A systematic review looking into endogenous oxytocin established that plasma levels of oxytocin are inversely related to depressive symptoms.7 Breastfeeding women overall had higher levels of plasma oxytocin, and breastfeeding mothers who had positive depression screenings had a lower level of plasma oxytocin. In women who did not have depressive symptoms, oxytocin was protective against cortisol release in response to stress, but in breastfeeding women with depressive symptoms, there was an abnormal cortisol response to stress.7 This suggests that postpartum depression may impact the relationship between oxytocin and cortisol release as a stress response.
Multiple systematic reviews indicate that, when successful, breastfeeding is protective against the development of postpartum depression.1,5,6 These systematic reviews cite many factors that could lead to breastfeeding complications, like duration of breastfeeding, breastfeeding experiences, and having a pre-existing mental illness. The number of studies in this review was limited, therefore these results would need to be replicated with more studies to hold significant value.7 This shines a light into a potential relationship between oxytocin and postpartum depression and potentially gives an explanation behind the pathophysiology of the disease, and what things can cause dips in oxytocin, leading to an increase in depressive symptoms.
Healthy People 20304 has listed an objective (“Increase the proportion of women who are screened for postpartum depression at their postpartum checkup”) which emphasizes the need for broader screening for postpartum depression. There have been many studies that have tried to address particular risk factors for postpartum depression, and among those have been breastfeeding. The effects that breastfeeding has on postpartum depression, specifically if it can be considered a protective or a risk factor, have mixed data in research. This research is important for family medicine and obstetric providers to identify at-risk populations of mothers during the postpartum period and to potentially indicate a wider screening population for postpartum depression. This paper aims to review recent studies looking at breastfeeding duration, mother-infant bonding, and antenatal depression and review their relationship to postpartum depression.
Recommended Citation
Crowley, Brooke; Roman, Kara; Olmstead, Andrea; Morris, Jaydeen; and Brumitt, Jason, "A Review of Factors that Impact Breastfeeding and Postpartum Depression" (2024). Doctor of Medical Science (DMSc). 34.
https://digitalcommons.georgefox.edu/dmsc/34