Is there any way to know if my health problems were caused by or made worse by pregnancies?

Yes, pregnancy can definitely lead to major nutritional deficiencies and poor health in mothers. Pregnancy is a huge burden nutritionally. 

A lot of the mother’s nutrition is given to the baby. The baby’s growth and development is prioritized, and then the mother suffers as a result. The mother’s nutritional reserves end up being depleted.  

You lose a lot of nutrients when you’re pregnant. That’s why many women end up having health issues after pregnancy, including postpartum depression.