Exercise and Pregnancy - Always Consult Your Physician

It is commonly asked whether pregnant females can exercise safely. The simple answer is yes; especially in the case of those who were active prior to pregnancy. Those active prior to pregnancy should be able to continue their regular activities unless advised otherwise by a physician. However, it is never too late for women who are inactive prior to pregnancy to begin an exercise program.

*Always consult your physician before beginning any exercise program

Generally speaking, exercise is highly recommended for preparing a woman's body for carrying and delivering a child and for improving the health of the unborn baby. Starting an exercise program may also help a pregnant woman reduce or prevent feelings of anxiety, tension, fear, and panic about childbirth.

Many physicians believe that prenatal exercise should be a critical part of a woman's pregnancy. It is recommended that pregnant females do at least 150 minutes of moderate-intensity exercise and three days of resistance training each week. However, it is estimated that fewer than one in four pregnant women meet the minimum recommendations for physical activity during pregnancy. Exercise can help a pregnant woman connect to her mental and emotional state and enjoy a more balanced, healthy pregnancy and postpartum period.

Physiological and Anatomical Changes During Pregnancy

A woman's body goes through many changes during pregnancy, and these changes impact nearly every organ system in her body.

Pregnancy is divided into three trimesters, and each trimester is approximately 12 weeks. Many of the major physiological and anatomical changes will happen within the first and second trimester alone.

In the first trimester of pregnancy, important hormonal changes occur. At the time of pregnancy, progesterone levels increase to develop the lining of the uterus, which supports the fertilized egg as it implants to grow. For clarity, progesterone are female hormones that regulate the menstrual cycle and are crucial for pregnancy.

Other hormones involved include relaxin, which are a sex hormone that facilitate birth by causing relaxation of the pelvic ligaments. These hormone are released from the corpus luteum in the ovary and eventually the placenta. These hormone will reach their highest levels during the first trimester.

Other joints can also become more flexible, which can limit the body's ability to stabilize itself. There is an increase in the elasticity of muscles and tendons, which can lead to reduced muscle actions during exercise. There will also be an increase in the elasticity and size of the heart, veins, and arteries, leading to dilation of blood vessels.

During the second trimester, biomechanical changes will create new challenges. As the baby grows within the uterus, there is a significant shift in a woman's center of gravity, causing the pelvis to tilt forward. This may encourage poor posture and create low-back pain in some women. Additionally, a woman's weight will naturally increase with the growth of the baby, and there may be a need to urinate more frequently as the uterus presses on the bladder.

In the third and final trimester of pregnancy, dramatic physiological changes slow, but the increase in body weight will likely continue to affect the woman. A growing baby may compress the major blood vessels that run to and from the heart when the pregnant woman is lying in a supinated position, which can cause a drop in blood pressure, feelings of lightheadedness, as well as a reduction of blood flow to the bay. For this reason, it is recommended that pregnant women limit the amount of time in back-lying positions.

In many cases, there are significant differences in weight gain between those who exercise during pregnancy and those who do not. Postpartum BMI (Body Mass Index) is lower for women who exercise than for those who do not, and women who enter pregnancy overweight and do not exercise may experience a more difficult delivery. By continuing or beginning a fitness program during pregnancy, women may improve their general health and physical function, reduce bodily pain, have more energy to participate in fun social activities, and enjoy pregnancy.

Special Considerations for Pregnancy

It is important for pregnant women to obtain clearance from their doctor before continuing or beginning an exercise program while pregnant. In most cases a letter from a physician will be necessary to continue exercising.