Back pain may occur as early as your first trimester of pregnancy.
While there's plenty to be excited about during pregnancy, many women encounter some uncomfortable pregnancy symptoms during the 40-week stretch. The additional weight of the baby, an expanding uterus, the placenta and increased blood volume all put more strain on a pregnant woman's back. The American Pregnancy Association notes that 50 to 70 percent of pregnant women experience back pain.
Placement
Lower back pain caused by pregnancy has many causes. Your body is adapting to meet the needs of your growing fetus, meaning your internal organs must shift while your uterus stretches over time. All of this movement and shifting takes its toll on your body and may cause lower back pain. Lower back pain can range from a sharp pain to a dull throb. According to BabyCenter, there are two types of pregnancy-related lower back pain: lumbar vertebrae pain (what most people typically think of when they think of lower back pain) and posterior pelvic pain, which is lower down on your pelvis.
Strain
When you're pregnant, you need to pay special attention to your body. While you may be fortunate enough to feel bursts of energy (common during the second trimester), you can easily cause yourself pain by pushing your body too hard while exercising, cleaning or doing other routine activities. Evidence that you're straining yourself includes a sudden sharp pain in your back, the feeling that you may have pulled a muscle, or pain when you bend or twist your back a certain way.
Labor
If you've experienced back pain throughout your pregnancy, it may be easy to dismiss it. You should pay attention to any unexplained or sudden lower back pain that may occur, especially as you approach the end of your pregnancy. According to the Mayo Clinic, "A low, dull backache may be a sign of preterm labor. And severe back pain or back pain that's accompanied by vaginal bleeding or discharge may indicate an underlying problem that needs attention." Anytime you feel unsure of your symptoms, call your healthcare provider to discuss your situation.