Thanks for writing to us.
The constant pain in the back could be due to a uterine contraction, sprain
or overuse fatigue
of the back muscles. Rest and hot fomentation with mild pain killers will help in providing the desired relief.
I hope this information has been both informative and helpful for you. You can consult me again directly through my profile URL http://bit.ly/Dr-Praveen-Tayal
Dr. Praveen Tayal