A nurse is assessing a client who is receiving oxytocin infusion to augment labor. Which of the following findings should the nurse identify as an adverse effect of the medication?

Choice A reason: Prolonged uterine contractions lasting 90 seconds indicate uterine tachysystole, a dangerous adverse effect of oxytocin. This can reduce placental perfusion, compromise fetal oxygenation, and increase risk of uterine rupture. Immediate intervention is required. Choice B reason: Moderate variability of the fetal heart rate is a reassuring sign of adequate oxygenation and intact neurological function. It is not an adverse effect. Choice C reason: Contractions every 2 minutes are within the normal therapeutic range for oxytocin augmentation. This frequency supports labor progression without compromising fetal well-being. Choice D reason: A fetal heart rate of 150/min is within the normal baseline range (110–160/min). This is not an adverse effect.