The main reason you're achy is because your body is producing more of a hormone called relaxin, which keeps your ligaments loose so your baby can pass through your pelvis more easily. This relaxin surge begins shortly after you conceive, peaking in the second trimester (when most back pain begins in earnest), and remaining steady until a few days after you deliver. If your core muscles (your abs and others) aren't strong enough to compensate for this newfound flexibility, while still supporting the weight of your belly -- and most of ours aren't -- your pelvic joints will become less stable and cause pain. This puts more strain on your spine, resulting in pain around your lower back and hips.
In rarer cases, your back pain may be exacerbated by a condition called diastasis, in which your ab muscles become separated as your uterus expands. If the split is large, it can make lower-back and pelvic pain conditions in the pregnancy worse. If this happens, it won't harm you or your baby, but you may need some physical therapy during pregnancy or after delivery.
Back pain during pregnancy is somewhat unavoidable, but these tips can help minimize your discomfort:
- Swap your stilettos for comfy flats.
- Book a prenatal massage. It's great for boosting circulation and for relieving muscle aches (and you totally deserve the extra pampering, anyway!).
- Avoid standing for long periods of time. If your job demands it, take breaks to do sit or stretching exercises.
- If you have to pick something (or someone) up, be sure to bend at the knees, not from your waist.
- When it's time for bed, sleep on your side with a pillow tucked between your knees for extra support (this will help minimize stiffness you may feel when you wake up, too).
- Try this exercise to help align your pelvis: Lie on your back with your knees bent and your feet flat on the floor. Place a rubber ball between your knees and gently squeeze it for 5 seconds. Do 3 times.
Of course, if your pain is debilitating (meaning you can't go to work, perform simple chores, or even walk) ask your doctor to refer you to a physical therapist. In many cases, the problem can be solved in just a few sessions.