Infectious diseases obviously affect us; our personal health, and the personal health of other people. If someone else has an infectious disease then you would probably stay away from such a person. If you had an infectious disease, other people would probably stay away from you. This isn't true for noninfectious diseases where we don't have to worry about infecting or being infected by other people.
They reduce pregnancy because the delay the uterus releasing the egg, and delay ovulation. Less than 1% of women who use IUDs pregnant, although pregnancies after the emergency contraceptive pill are not as rare.
Tables are helpful for presenting and analyzing simple numeric data collections.
Hope this helps