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. Author manuscript; available in PMC: 2020 Nov 27.
Published in final edited form as: Am J Obstet Gynecol. 2019 May 7;221(3):259.e1–259.e16. doi: 10.1016/j.ajog.2019.04.037

TABLE 2.

Labor and delivery outcomes of women in IMPROVE study

N = 152, 24 censored N = 148, 34 censored Pvaluea HR [95% CI]a Pvaluenoninferiority
Time to delivery (hours), median [95% CI] 20.1 [18.2, 22.8] 28.1 [24.1, 31.4] .006 0.70 [0.54, 0.90] .663
VM group (n = 152) BM group (n = 148) Pvalueb
Cesarean for fetal nonreassurance, n (%) 5 (3.3) 14 (9.5) .033
Vaginal delivery in less than 24 hours, n (%) 89 (58.6) 58 (39.2) .001
Reason for stopping misoprostol, n (%) .006d
 Onset of active labor 7 (4.6) 10 (6.8)
 Sufficient cervical ripening 60 (39.5) 43 (29.1)
 Safety concerns 47 (30.9) 34 (23)
 Multiple reasons 31 (20.4) 38 (25.7)
 Other 7 (4.6) 23 (15.5)
Route of delivery, n (%) .151
 Vaginal delivery 127c (84.2) 115 (77.7)
 Cesarean delivery 24 (15.8) 33 (22.3)
Cesarean (indications), n (%) N = 24 N = 33 .376d
 Fetal nonreassurance 5 (20.8) 14 (42.4)
 Arrest of dilation 3 (12.5) 4 (12.1)
 Arrest of descent 3 (12.5) 1 (3.0)
 Multiple reasons 11 (45.8) 11 (33.3)
 Other 2 (8.3) 3 (9.1)
Chorioamnionitis, n (%) 7 (4.6) 10 (6.8) .420d
Postpartum hemorrhage, n (%) 8 (5.3) 6 (4.0) .620d
Blood transfusion, n (%) 1 (0.6) 1 (0.7) .794d
Oxytocin use, n (%) 100 (65.8) 111 (75) .081
Doses of misoprostol needed to get into active labor (n), median (range) 2.0 (1.0–5.0) 3.0 (1.0–7.0) <.001d
Maximum units of oxytocin administered, median (range) 4.0 (0–36.0) 6.0 (0–30.0) .001d

P value for noninferiority hypothesis based on Cox proportional hazards model (H0: HR ≤ 0.74 vs HA: HR > 0.74); P value < .05 provides evidence to reject inferiority and conclude BM is noninferior to VM.

BM, buccal misoprostol; CI, confidence interval; HR, hazard ratio; VM, vaginal misoprostol.

a

P value from log-rank tests; profile likelihood confidence intervals reported for 95% CI of HR;

b

P values obtained from t test (continuous) or χ2 test (categorical);

c

One subject was admitted into the study, got discharged, and then returned 2 weeks later to have a vaginal delivery. Delivery characteristics (except for route of delivery) are included for this person as they were censored for time to delivery;

d

P values obtained from Wilcoxon rank sum test (continuous) or Fisher exact test (categorical).