I get that, but not during my pregnancies only... I have herniated discs in my lower back.. L3-L4, L4-L5, and L5-S1. I fractured one of my discs in my lower back and my C2 (neck) in a car accident... It causes all kinds of crazy numbness. Still no help/ my advice... If any dr. advices u to get a steroid injection in any part of ur body, it hurts really back, helps for sh*t, and back where u started. I also was born with spina bifida occulta. Which also causes problems in all those areas... the weight u might b putting on during pregnancy could be compressing ur spinal cord, do some stretches. Like sitting in a chair (if u can) or just bend over, and stretch out those vertebrae. Best wishes..

Hope that helps... I've been threw enough physical therapy to know how to stretch those areas out~ best wishes, and congrats on ur mommyhood~~