Objective: to study the true determinants of adverse perinatal outcome (APO) in term healthy mothers with normal cardiotocograph (CTG), evaluating the real influence of maternal age.
Material and methods: In a retrospective study, we assessed a group of 529 term healthy mothers with normal CTGs that regardless of maternal age, evolved spontaneously up to 41 ± 2 weeks. The result of the conservative management was evaluated by means of univariable and multivariable logistic regression analysis, determining the association of maternal age and other clinical and ultrasonographical parameters with APO.
Result: In contrast with low CPR MoM (OR = 0.155, p = .014), induction of labor (OR = 2.273, p = .023) and low parity (OR = 0.494, p = .026), maternal age and birth weight centile did not prove to be true determinants of perinatal outcome. The multivariable model for prediction of APO using clinical parameters presented a sensitivity of 35% and 27% for a false positive rate of 10% and 5%, AUC 0.736 (95% CI 0.655-0.818), p < .0001).
Conclusions: in healthy old mothers with normal CTGs at term, APO is determined by low CPR, the existence of labor induction and low parity, while no real influence was observed for maternal age, fetal smallness, and interval examination-delivery. These results do not support the current consensus on induction at earlier weeks to prevent adverse outcomes in all cases of advanced maternal age, advocating for a more individualized, customized, and less interventional management based on fetal hemodynamics.
Keywords: Doppler ultrasound; fetal smallness; labor induction; late-onset fetal growth restriction.