I had back X-rays recently and may have been pregnant at the time. What are the chances of X-rays hurting a developing baby?
In general, the amount of radiation exposure a mom-to-be gets from diagnostic X-rays for a back problem is not enough to hurt the baby. Most people find it reassuring that significant radiation exposure in early pregnancy is thought to mostly cause an "all or none" phenomenon: either you miscarry or the baby is fine.
Radiation doses are measured in rads or centigray (cGy). The dose that can cause miscarriage is estimated to be about 10 rads. In general back X-rays deliver about a third of a rad to the fetus. So from what I can guess, the risk of radiation-induced birth defects in your case is extremely low.
Because I can't give you advice for your individual situation, I would recommend talking to your doctor or midwife to review the amount of radiation exposure you may have received. Overall, I think you can feel reassured that a health effect on your baby is quite unlikely.