Final answer:
A patient with placenta previa needs to deliver by C-section when there is active bleeding, regardless of the gestational week.
Step-by-step explanation:
In the case of placenta previa, a patient needs to deliver by C-section when there is active bleeding, regardless of the gestational week. Placenta previa is a condition in which the placenta partially or completely covers the opening of the cervix. It can lead to profuse vaginal bleeding, which poses a risk to both the mother and the baby.