Explanation

(i) Progesterone is a steroid hormone secreted by corpus luteum (ii) Progesterone is responsible for maintenance of pregnancy, hence called pregnancy hormone by maintaining the endometrium wall (iii) Hyposecretion of progesterone result in abortion. It is also called anti-abortion hormone (iv) During pregnancy progesterone helps in attaching embryo to uterine wall, development of placenta and growth of secretory alveoli in mammary gland