Yaz Tablets 28'SActive ingredient is ethinylestradiol 0,02 mg((an oestrogen) and drospirenone 3 mg(a progestogen) It is a combined oral contraceptive consisting of 24 pink tablets with active ingredients and 4 white inactive tablets These hormones prevent an egg being released from your ovaries so you cant get pregnant, It also makes the fluid (mucus) in your cervix thicker which makes it more difficult for sperm to enter the womb.