Oh and you're only 31 weeks- why would you have a c-section in 4 weeks? Pregnancy is 40 weeks for a reason. Unless your life or the baby's life are in danger there is no reason to induce before 39 weeks. Your baby stands a better chance of survival and health when born after 39 weeks.
The ACOG states that an estimated large baby is NOT a medical reason for induction or c-section. You can also refuse. If you suspect you're having a large baby by the time you deliver pushing in a squatting position will open your pelvis up very wide to help get baby out.
Women can deliver large babies. There's no reason to assume you'll have a c-section because you feel you're measuring larger. You can measure larger for many reasons other than a large infant.
Yeah, 36cm isn't overly large for the baby at 31 weeks. Was it the baby or your uterus that was measuring 36cm? (Because your uterus usually measures the week you are, so if you are 31 weeks it would be around 31cm).
36cm is only 14-15 inches which is perfectly fine. At 31 weeks it can measure up to 16 inches. Did someone say you would need a c-section?