Table 4

 Likelihood ratios of historical variables for being pregnant

Positive HCGLR+95% CI
CI, confidence interval; HCG, human chorionotropic gonadotropin; LMP, last menstrual period; LR+, positive likelihood ratio.
Yes to “might be” (n = 30)610.535.51 to 20.47
Yes to “chance pregnant” (n = 137)103.232.59 to 4.17
LMP not on time (n = 113)72.361.36 to 4.11
LMP not normal (n = 125)51.750.91 to 3.39
No birth control (n = 242)81.711.19 to 2.48
Sexually active (n = 344)111.371.30 to 1.45