Backache in during pregnancy is extremely common.
What is the reason of this?
Backache, in particular, usually occurs between the fifth and seventh months of pregnancy, but it can start earlier or later and is often caused by changes in your hormones and center of gravity, as well as in response to the weight your body adds.
Most low back pain during pregnancy is caused by stress on the lumbar spine, which is where the spine bends. Due to the increase in the hormone relaxin during pregnancy, the attachment and relaxation of the tendons can pull the lumbar spine further than normal.
Backache usually disappears after pregnancy, like most back pain that didn't happen before pregnancy. Low backache is usually centered above the lower back, in the mid-back, but may extend along the spine or into the sacrum and upper thighs.
Tips
Low backache is common, but usually manageable – if you have trouble managing low back pain or it doesn't disappear for more than two weeks, this may be a sign that it's time to talk to your healthcare provider.
Flat shoes: Shoes with good arch support can support posture, which helps prevent back pain, such as wearing low heels instead of full flat shoes. High heels can also cause back pain.
Start your day right: Sleeping on your side instead of on your back can help you by reducing the stress and weight that your spine will support. Using pillows between your knees, under your stomach, and behind your back can also help you distribute your weight better while lying down.
Hot and cold: Both heat packs and ice packs can be helpful to relieve back pain as massage. Heat is usually better for prolonged pain; ice may help when the pain first appears. Heat packs or short, warm baths can help relieve long-term back pain well.
Give it a shot: Certain ways to deal with maternity back pain, such as support belts or chiropractic work, may not be scientifically proven to work, but many women still find them helpful.
Back pain during pregnancy is both common and usually relatively harmless, but it can be frustrating. Sudden, intense lower back pain can be a sign of preterm birth, especially if you're at a higher risk for preterm birth or if the pain moves in waves like contractions.
Other symptoms that occur alongside low back pain can also be signs of potential complications. These include: vaginal bleeding, fever, burning sensation when urinating, your back pain not responding to pain relievers, vomiting, nausea, sweating, sudden changes in bowel or bladder control.

