Folic acid deficiency is attributed to the cause of spina bifida. Type increasing you folic acid rich foods. I think asparagus is a big one but, search the FDA and .org websites for an accurate list.
I'm not at all familiar with it but I'd like to send good vibes your way and tell you a little story that happened to a good friend of mine 6 years ago. She was pregnant with her first and was a told the same thing during her scan. She choose to not follow the remaining test, a few months later she gave birth to a healthy baby boy and was misdiagnosed. He did not have spina bifida. Good luck. Prayers your way.