Betnesol injection contains the active ingredient betamethasone sodium phosphate, which is a type of medicine known as a corticosteroid. It is indicated if any pregnant women is at high risk for preterm delivery or have threatened preterm labor. Injections of corticosteroids is used for fetal lung development. The injections had to be given 24-48 hours prior to the birth for maximum effect. The use of the steroids provided benefits for the lung development in the premature infants to reduce the risk of respiratory distress syndrome (RDS) as well as to reduce the risk of intracranial hemorrhaging and some other potential benefits. A term pregnancy is defined as a pregnancy at 37 weeks. In your wife case as you told its correct that she is in term pregnancy. The reason why she has been advised betnesol injection you should better ask this to your doctor. Your doctor might have thought it is necessary for some other reason. But Unnecessary betnesol injection should be avoided. Regards Dr Santosh