Evaluation of glyceryl trinitrate, misoprostol, and prostaglandin E2 gel for preinduction cervical ripening in term pregnancy.
OBJECTIVE
To compare the efficacy of glyceryl trinitrate (GTN), dinoprostone and misoprostol for preinduction cervical ripening in primigravida at term.


METHODS
Sixty-five term primigravida, each with an unfavorable cervix (Bishop score </=5), were randomized to receive GTN (0.5 mg perivaginally, n = 21), dinoprostone gel (0.5 mg intracervically, n = 21) and misoprostol (50 microg perivaginally, n = 23) for a maximum of two doses, 6 h apart. Statistical analysis included paired t-tests to compare pre- and post-treatment Bishop scores, one-way analysis of variance (anova) tests to compare quantitative variables and chi-squared tests to compare the proportion of subjects achieving favorable Bishop scores.


RESULTS
Baseline Bishop scores were similar in the GTN (3.4 +/- 0.9), dinoprostone (3.4 +/- 1.0) and misoprostol groups (3.2 +/- 1.2). The final outcome was favorable (Bishop score >6) in a greater proportion of subjects in the misoprostol (n = 18, 81.8%) and dinoprostone (n = 14, 66.7%) groups compared with the GTN group (n = 11, 55%). In subjects with a severely unfavorable cervix (Bishop score </=3), treatment with misoprostol led to a favorable response in 61.6% of patients compared with 45.6% in the misoprostol group and 33.3% in the GTN group. A significant improvement was noted in the Bishop score of all three groups (P < 0.001) but the increase in Bishop score was greater in misoprostol (3.5 +/- 2.1) and dinoprostone groups (2.8 +/- 1.5), compared with the GTN group (2.0 +/- 1.0, ANOVA F = 4.8, P = 0.01). Hyperstimulation and tachysystole were observed only in the misoprostol (9% and 4.3%) and dinoprostone groups (4.7% and 16.2%). The most common adverse effect in the GTN group was headache, which was observed in 47.6% of this group's subjects.


CONCLUSIONS
The findings of the present study suggest that GTN is safer, but less efficacious, compared with prostaglandins for preinduction cervical ripening at term.
Sharma
Yuthika
Y
Department of Obstetrics and Gynecology, All India Institute of Medical Sciences, New Delhi, India.
Kumar
Sunesh
S
Mittal
Sunita
S
Misra
Renu
R
Dadhwal
Vatsla
V
D000282:Administration, Intravaginal; D020070:Cervical Ripening; D015232:Dinoprostone / Q000008:administration & dosage; D005260:Female; D005782:Gels; D006801:Humans; D007745:Labor Onset; D016595:Misoprostol / Q000008:administration & dosage; D005996:Nitroglycerin / Q000008:administration & dosage; D010120:Oxytocics / Q000008:administration & dosage*; D011247:Pregnancy; D011446:Prospective Studies; D016896:Treatment Outcome
D005782:Gels; D010120:Oxytocics; D016595:Misoprostol; D005996:Nitroglycerin; D015232:Dinoprostone