ABSTRACT
An old theory of postpartum depression is that it is caused by the drop in estrogen and progesterone. That theory has little empirical support. The most that can be said is that estrogen shifts may increase the risk in some women. Thyroid can also be related to depression, but it is a small percentage of women affected. However, some women, such as those with diabetes or who are very fatigued, may be at increased risk, so it can be worth testing for.
