Is your baby a very calm, quiet and good baby? Does he/she remain sleepy all the time? Not interested in feeding, but surprisingly gaining weight? Not passing stool daily? If the answers are ‘Yes’, you must think of Congenital Hypothyroidism. Now the question arises what is Congenital hypothyroidism (CH)? It can be defined as the lack of thyroid hormones since birth results from complete or partial loss of thyroid (a butterfly shaped gland situated at the lower neck) function. If it is not detected and treated early, it can cause irreversible brain damage and poor mental development. What is the cause? May be defect (structural or functional) in the major hormone producing glands like pituitary and/or thyroid, use of some anti thyroid medications (carbimazole) by mother or due to iodine deficiency. At birth baby may be normal, but gradually develops feeding problem, excessive sleepiness, less activity, low frequency of crying, constipation, prolonged jaundice( yellow skin, eyes, urine) persisting more than 14 days after birth and so on. By 3 months features of hypothyroidism come out completely. There may be protrusion of tongue, hoarseness of voice while crying, low body temperature, rough skin, swollen mass over the neck (goiter), excessively gaining weight etc. As delay in identifying this problem can cause irreversible brain damage and low IQ level, every baby should be screened after birth for congenital hypothyroidism. This test is usually carried out on the 5th day after birth via a simple pinprick collection of blood and analysis of TSH, T4 hormones. It is a part of newborn screening program throughout the world but not well established in Bangladesh. The aim of this screening is early detection and hormone replacement to halt all these disabilities. It can be serious if not diagnosed early but it is a completely treatable disease. If your doctor suggests the screening of hypothyroidism for your newborn baby don’t say ‘Not Now’.