(a) The two commonly used IUDs are copper releasing IUDs (e.g. CuT) and hormone releasing IUDs (e.g. Progestasert).
Cu ions released from the IUD suppress sperm motility and the fertilising capacity of sperm. Hormone releasing IUD make the uterus unsuitable for implantation and the cervix hostile to sperm. [2 marks]
(b) Sterilization is adviced to married couples as a terminal method to prevent any more pregnancies. [1 mark]
Sterilisation procedure in male is called vasectomy
and that in the female is called tubectomy. In vasectomy, a small part of the vas deferens is removed or tied up through a small incision on the scrotum. In tubectomy, a small part of the fallopian tube is removed or tied up through a small incision in the abdomen or through vagina. [2 marks]