Strong core muscles during pregnancy help to support your posture, protect your back, and may even assist you during delivery. You can maintain strong abdominal muscles during pregnancy with exercises that are safe and effective. After the third month of pregnancy, the American Congress of Obstetricians and Gynecologists recommends that pregnant women avoid performing exercises while lying face up on their back. Fortunately, supine exercises such as sit ups and the abdominal crunch are not the only way to strengthen the core.

Always speak with your physician before beginning any exercise program. Pay attention to how your body is feeling. This is not a time to make strength gains but to maintain core stability.  If you experience any pain, dizziness, bleeding or fluid leakage, stop the exercises immediately and seek medical attention.

Abdominal Bracing

Abdominal bracing is an abdominal-strengthening exercise you can perform anywhere. The exercise is classified as an isometric, as it does not involve movement. You tighten your abdominals by pulling your navel toward your spine. Begin in a seated position with your knees bent and your feet flat on the floor. Breathe normally as you perform the abdominal bracing maneuver and aim to maintain the contraction for one second and then relax your core. Repeat the contraction 10 to 12 times. Gradually increase the duration of the contraction between three and four seconds, then to five seconds and eventually to 10 seconds. Once you have mastered the abdominal bracing in a seated position, try the exercise while standing and then while on your hands and knees. You can perform this exercise while driving, washing dishing, watching television or reading.

Abdominal Sit-Backs

An abdominal sit-back exercise is the opposite of a sit-up. Instead of curling up from a lying position, you slowly sit back from an upright position. Sit in bed with your knees slightly bent and your heels resting on the bed. Place your arms across your chest. Straighten your spine and sit up as tall as possible. Perform the abdominal bracing and tighten your core to support your back by pulling your belly button toward your back. Slowly sit back as you maintain your lifted chest and straight spine. Sit back to the point you feel your core contract and you are able to keep your feet on the bed. If you sit back too far, your feet may come off the bed. Return to the upright position and then repeat. Aim to complete 10 to 12 sit-backs as you inhale when you sit back and exhale as you sit up. Begin with one set and gradually increase to two or three. Perform the exercise three times a week with a day of rest in between. To increase the challenge, straighten your arms away from your chest, or raise your arms overhead.