How old were you when you began using oral contraceptives:Time:Pt:^Patient:Qn:PhenX
how old were you when you began using oral contraceptives:time:pt:^patient:qn:phenx
How old were you when you began using oral contraceptives:Time:To identify measures at a point in time:^Patient:Quantitative:PhenX
how old were you when you began using oral contraceptives:time:to identify measures at a point in time:^patient:quantitative:phenx