A stranger's elbow here, a kitchen counter there -- as your pregnancy progresses, you may feel like your abdomen's on a collision course with the world. It's not just your imagination: Many factors during pregnancy make your belly bump-prone, such as loose ligaments and joints, a growing girth (you're a larger target and a little off-balance), and a feeling of being somewhat distracted.

There's no need to worry every time you bump your tummy; even a front-forward fall or a kick from your toddler is unlikely to hurt your baby-to-be. "Mother Nature provides a safe and protected environment for a fetus, which floats in amniotic fluid in the amniotic sac, which in turn is protected by the muscles of both the uterus and the abdomen," says Owen Montgomery, M.D., assistant professor of obstetrics and gynecology at Allegheny University of the Health Sciences. The spine in back and the pelvis and rib cage in front also form bony barriers.

Even so, let your obstetrician know if you've taken a spill directly onto your belly, if you've been in a minor fender bender, or if you've suffered a blow to your stomach from another adult. He may have you come in to monitor the fetal heart rate. Seek immediate medical attention if your baby isn't as active as before (movement about five times in a two-hour period when you're lying down is normal if you're in your second or third trimester), or if you have bleeding, vaginal discharge, contractions, or cramping within 12 hours of an incident.

Take extra precautions to be safe from slipping. Watch out for ice, snow, and wet leaves, and newly waxed or mopped floors. Wear sensible shoes -- no slick soles or high heels -- that fit properly. Be careful getting in and out of the tub or shower, and use the handrails on stairs. And always wear a seatbelt with the lap portion under your abdomen and the shoulder strap between your breasts and to the side of your belly.

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