The correct answer is choice D. A planned Cesarean section increases the rate of unexplained stillbirths at or after 34 weeks in future pregnancies. This is because a prior Cesarean section can cause placental abnormalities such as placenta previa and placenta accreta, which are associated with increased risk of stillbirth.

Choice A is wrong because the evidence comparing the risks of planned Cesarean section and vaginal delivery is mainly low or moderate quality. There are many confounding factors that can affect the outcomes of different modes of delivery, and most studies are observational and not randomized.

Choice B is wrong because the immediate maternal risks from a planned Cesarean section are not significantly higher than those of a planned vaginal delivery. However, a planned Cesarean section is associated with higher risks of infection, thromboembolism, wound complications, and longer hospital stay than a planned vaginal delivery.

Choice C is wrong because a vaginal birth is not associated with a comparable or higher maternal mortality rate than planned Cesarean section. The maternal mortality rate for planned Cesarean section is 0.01% and for planned vaginal delivery is 0.02%, which means there is no significant difference between the two modes of delivery.

Choice E is wrong because there is no evidence that an association exists between a prior Cesarean section and subsequent preterm birth, fetal growth restriction and spontaneous miscarriage.

These outcomes are more likely to be influenced by other factors such as maternal age, medical conditions,