A lot of doctors don't recommend having more than three c-sections because the incision area could become weak. However, you should be fine despite having another one.
The more c-sections a mother has the greater the risk to the mom. Increased C-sections increase the likely hood of a ruptured uterus. You should consult with medical professional to determine what is safest for you.
It is certainly safer than attempting a vaginal birth after so many C-sections. There are no additional risks if the previous 3 went smoothly. Any previous problems may repeat, though.
