Explain how do the following act as contraceptives: (a) CuT (b) "Saheli"

(a) CuT (copper T) is an Intra Uterine Device (IUD) that releases copper ions. It increases phagocytosis of sperms within the uterus, suppresses sperm motility and reduces fertilizing capacity of sperms. (b) Saheli is an oral contraceptive pill for females which contains a progesterone and oestrogen combination. It inhibits ovulation, implantation and also modifies the quality of cervical mucus to prevent or reduce sperm entry.