Aim: To study the effect of vaginal pH on the efficacy of the dinoprostone gel for cervical ripening/labor induction and the effect on fetal and maternal outcomes.
Methods: A prospective study over one year was conducted and all term pregnancies with induced labor and who satisfied the inclusion criteria were screened for enrollment. Total of 500 subjects was enrolled in this study. These subjects were divided into two groups, group I (pH <5.5) had 199 subjects, group II (pH ≥5.5) had 301 subjects.
Results: Overall delivery outcome was better in group II (pH ≥5.5) as compared to group I (pH<5.5). Mean bishop score changes (over 12 hours) were also better in group II. Similarly, the need for the second dose, mean duration from induction to active labor and delivery was less, more subjects delivered vaginally, in group II (pH ≥5.5) as compared to group I.
Conclusion: Vaginal pH appears to be one important factor that influences the efficacy of PGE2 gel, results being better with high pH (pH ≥5.5).
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