Decreased level of thyroid hormone formed by pituitary is thought as hypothyroid disease and increased level of thyroid formed by pituitary is thought as hyperthyroid disease. Poorly treated or untreated maternal over thyroid sickness might have an effect on maternity outcome. The complicate health problems throughout maternity and baby area unit foetal and baby hypo or thyrotoxicosis and baby central glandular disease. Appropriate identification and treatment of hypothyroid and hyperthyroid disease throughout maternity time are of most important. Because as a result of thyroid disorder there will be many worse effects on both mother and child. Propylthiouracil and Methimazole can be considered as a drug which can treat thyroid disorder at the time of pregnancy and lactating period.