A Randomized Trial of Induction Versus Expectant Management (ARRIVE) trial has shown a reduction in adverse perinatal outcomes among low-risk nulliparous women at 39 weeks’ gestation following labor induction (4.3%) than expectant management (5.4%, P=0.049).
Although this difference was not statistically significant (since P=.046 is the significance threshold), interpreting these results by a Bayesian method and studying their conceptual importance is crucial.
The hypothesis of ARRIVE trial is a stand against the central paradigm of modern obstetrics because it overlooks maternal or fetal compromise as a prerequisite for early delivery. The P-value function founded on ARRIVE trial shows that study findings are not agreeing with even a modest increase in adverse perinatal outcomes after labor induction for 39 weeks’ gestation, while it agrees with a substantial reduction in adverse perinatal outcomes.
Physiological and epidemiologic evidence as well as meta-analyses of related randomized trials demonstrate that pregnancies follow little and gradual advancing risks of adverse outcomes at a later gestation.
Bayesian analysis, founded on previous randomized trials updated with ARRIVE trial results, also demonstrates that labor induction for 39 weeks’ gestation holds a protective effect regarding adverse perinatal outcomes. Obstetricians must be mindful of this risks-benefits balance regarding labor induction and expectant management at 39 weeks’ gestation and beyond. However, the ultimate valuation in decision making must take into account the principles of patient autonomy.
SOURCE- Joseph KS, John S, Boutin A. et al. Modern obstetrics: beyond early delivery for fetal or maternal compromise. AJOG-MFM, 2021;3(1). DOI:https://doi.org/10.1016/j.ajogmf.2020.100274