Erythropoietin is inhibited by -
Ans. is 'a' i.e., Estrogen o Estrogen antagonizes the erythropoietin-augmenting effect of placental lactogen. It inhibits utilization of erythropoietin by the marrow stem cell, and also impairs its production.
Estrogen
Progesterone
Thyroxine
Testosterone
Sex-Hormone