[Solved]: In the introduction to this case study, pregnancy was…

In the introduction to this case study, pregnancy was described as apparently protective against ovarian cancer. The investigators were interested in seeing whether the association between OC use and ovarian cancer differed for women of different parity. Parity = 0 45 were cases and 147 were controls. Amongst the cases, 20 have ever used oral contraceptives. Amongst the controls, there were 80 never-users of oral contraceptives. Parity = 1-2 68 were cases and 568 were controls. Amongst the cases, 42 have ever used oral contraceptives. Amongst the controls, there were 199 never-users of oral contraceptives. Parity = 3+ 65 were cases and 920 were controls. Amongst the controls, 30 have ever used oral contraceptives Amongst the controls, there were 400 never-users of oral contraceptives.