Causes of Postpartum Depression

No one knows the exact causes of postpartum depression. PPD is more than the baby blues; it lasts longer and is more severe. The "baby blues" typically resolves within about ten days after delivery. Postpartum depression lingers. The baby blues cause mild sadness and mood swings. PPD causes severe depression and loss of interest in life.

After pregnancy, progesterone levels fall drastically. Like progesterone, the levels of estrogen, a hormone that seems to be important in memory and mood, fall 90 to 95 percent in the first 48 hours following delivery. Thyroid levels may also drop sharply after birth.
 
A thyroid deficiency can produce symptoms that mimic depression, such as mood swings, severe agitation, fatigue, insomnia, and anxiety. A link between estrogen levels and postpartum depression has not been established and experts cannot agree on the role that hormone fluctuations play in postpartum depression.
 
Postpartum depression researchers are also investigating genetics as a cause of the disorder.

Possible Causes of Postpartum Depression
Emotional factors that contribute to postpartum depression include:

  • feelings of loss: loss of identity, loss of control, loss of body image
  • stress related to a woman's job and responsibilities outside and inside the home
  • a resurgence of sad feelings about past losses
  • a woman's personal history and feelings about parenting
  • deep concern and pressures about being the "perfect mother"
  • financial worries
  • sadness about having less time to spend with the baby's father.

Physical factors include:

  • shifts in the levels of hormones like progesterone, estrogen and thyroid during pregnancy and after birth
  • sleep deprivation and exhaustion, especially after a cesarean delivery
  • confinement to the indoors for long periods of time.

Who is at Risk for Postpartum Depression?

Postpartum depression affects many women, regardless of age, socioeconomic status, the number of children born, or the number of pregnancies.

Pregnancy itself can put a woman at risk for PPD. Any woman who has recently delivered a baby, miscarried, or weaned a child from breastfeeding can suffer from postpartum depression. In fact, even women who have adopted a child can suffer from postpartum depression symptoms; this is called post-adoption depression.
Women who are at a particularly high risk for PPD are those who:
  • have been victims of physical or sexual abuse, either in childhood or as an adult
  • have lost a child
  • have a family history of depression or anxiety disorders.
All women are at risk for PPD. However, a family history of depression or existing emotional troubles increase the risk of developing postpartum depression.

Resource

O'Hara, M.W. (1995). Postpartum depression. Series in Psychopathology, 1-27. Alloy, L. B. (ed). Springer-Verlag, New York.