Background: The rates of induction of labor and elective induction of labor are increasing. Whether elective induction of labor improves outcomes or simply leads to greater complications and health care costs is commonly debated in the literature.
Purpose: To compare the benefits and harms of elective induction of labor and expectant management of pregnancy.
Data sources: MEDLINE (through February 2009), Web of Science, CINAHL, Cochrane Central Register of Controlled Trials (through March 2009), bibliographies of included studies, and previous systematic reviews.
Study selection: Experimental and observational studies of elective induction of labor reported in English.
Data extraction: Two authors abstracted study design; patient characteristics; quality criteria; and outcomes, including cesarean delivery and maternal and neonatal morbidity.
Data synthesis: Of 6117 potentially relevant articles, 36 met inclusion criteria: 11 randomized, controlled trials (RCTs) and 25 observational studies. Overall, expectant management of pregnancy was associated with a higher odds ratio (OR) of cesarean delivery than was elective induction of labor (OR, 1.22 [95% CI, 1.07 to 1.39]; absolute risk difference, 1.9 percentage points [CI, 0.2 to 3.7 percentage points]) in 9 RCTs. Women at or beyond 41 completed weeks of gestation who were managed expectantly had a higher risk for cesarean delivery (OR, 1.21 [CI, 1.01 to 1.46]), but this difference was not statistically significant in women at less than 41 completed weeks of gestation (OR, 1.73 [CI, 0.67 to 4.5]). Women who were expectantly managed were more likely to have meconium-stained amniotic fluid than those who were electively induced (OR, 2.04 [CI, 1.34 to 3.09]).
Limitations: There were no recent RCTs of elective induction of labor at less than 41 weeks of gestation. The 2 studies conducted at less than 41 weeks of gestation were of poor quality and were not generalizable to current practice.
Conclusion: RCTs suggest that elective induction of labor at 41 weeks of gestation and beyond is associated with a decreased risk for cesarean delivery and meconium-stained amniotic fluid. There are concerns about the translation of these findings into actual practice; thus, future studies should examine elective induction of labor in settings where most obstetric care is provided.