Figure 2.

Kaplan–Meier plots of the prevalence of spontaneous preterm birth by gestational week of birth, according to ursodeoxycholic acid use and disease severity at randomisation

Analyses were done by use of individual participant data from women with singleton pregnancies participating in randomised controlled trials. Kaplan–Meier plots for all women (A), women with baseline bile acid concentrations less than 40 μmol/L (B), women with baseline bile acid concentrations between 40 μmol/L and 100 μmol/L (C), and women with baseline bile acid concentrations of 100 μmol/L or more (D). HRs compare women randomly assigned to ursodeoxycholic acid treatment with those randomly assigned to placebo. (E) All women by baseline bile acid concentration; HRs compare women with baseline bile acid concentrations of 40·0–99·9 μmol/L and 100·0 μmol/L or more to those with baseline bile acid concentrations less than 40·0 μmol/L. HR=hazard ratio.