Table 4 Odds ratios and 95% confidence intervals for hypertension and prehypertension by duration of oral contraceptive use

1.00 (reference)

0.97 (0.65–1.43)

1.63 (1.05–2.52)

2.42 (1.43–4.09)

<0.001

1.00 (reference)

0.99 (0.65–1.51)

1.22 (0.75–1.99)

1.96 (1.03–3.73)

0.012

1.00 (reference)

0.99 (0.68–1.43)

0.99 (0.64–1.53)

2.46 (1.44–4.19)

0.001

1.00 (reference)

1.00 (0.68–1.48)

0.86 (0.56–1.34)

2.23 (1.28–3.90)

0.010

1.00 (reference)

0.98 (0.71–1.34)

1.24 (0.90–1.73)

2.44 (1.63–3.66)

<0.001

1.00 (reference)

1.02 (0.72–1.43)

0.97 (0.68–1.38)

2.13 (1.37–3.32)

0.005