Question

In a pregnant woman having prolonged labour pains, its childbirth has to be hastened. It is advisable to administer a hormone that can

• A. Activate the smooth muscles
• B. Increase the metabolic rate
• C. Release glucose into the blood
• D. Stimulate the ovary

Answer 1

The correct option is A Activate the smooth muscles

During birth, prostaglandins initiate the contraction in smooth muscles of uterine wall which causes labor pains. The pressure of fetus’s head against the cervix and send signals to make hypothalamus to trigger the release of oxytocin from the posterior pituitary. Together, oxytocin (OT) and prostaglandins stimulate strong uterine muscle contraction forcing the fetus downwards and thereby expelling it out of the uterus. Thus, to hasten the childbirth, it is advisable to administer the hormone that stimulates uterine smooth muscle contraction i.e. oxytocin. This makes option A correct. Thyroxine is a thyroid hormone which targets all tissues and stimulates metabolic rate, growth, and development. Glucagon hormone from pancreas stimulates the liver to break down glycogen into glucose and use of fat and protein as glucose source thereby increasing the blood glucose level. Options B and C incorrect as these hormones have no effect in parturition. Gonadotropic hormones (FSH and LH) stimulate ovary for egg production and release of sex hormones (estrogen and progesterone). Hence, makes option D incorrect as estrogen and progesterone are maintained at a minimal level to facilitate parturition. Thus, the correct answer is A.