Hello, Since you already have two kids & are taking antidepressants presently, you are suggested to get your depression treated before you conceive. At times, moderate to severe depression may cause low birth weight, preterm birth, heart defects, miscarriage, etc. However, if you conceive you will need your doctor s assistance throughout the pregnancy. Since you have a history of thyroid, you will have to be on medications even during pregnancy. You will require to get closely monitored by your treating doctor as you will need to take the correct dose of the medications to avoid complications like miscarriage, still births or preterm births, maternal heart failure, etc. Hope I have answered your query. Let me know if I can assist you further. Take care Regards, Dr Nupur K, General & Family Physician