Pregnancy and Bodily Changes
During pregnancy hormones increase. Primarily Progesterone, and Estrogen, causing a variety of physiological changes, which become increasingly more prominent as pregnancy continues.
Water Retention and Venous (veins) Dilation:
One of the early changes is that of water retention, and venous dilation. The body, in preparation for the need of extra blood volume to the growing uterus, begins to retain water, and make more red cells. The general water retention leads to breast tenderness, and dilations of all veins.
Some patients can develop significant discomfort from the dilated veins in the lower half of the body, interfering with exercise, and even normal daily activity. These women may benefit significantly from hydrotherapy.
Swimming, and gentle exercises in a swimming pool helps reduce the side effects of vein dilation by pushing fluids back into the body’s trunk, and core. Many patients will notice dramatic improvement in the swelling of the feet, legs, and perineal areas after even short periods of pool therapy.
Drop in blood pressure and increase in basal heart rate:
Women whose baseline pulse may be 70-80 when not pregnant may find themselves with a pulse of over 100 when at rest during pregnancy. Again, the drop in vascular resistance caused by progesterone leads to an increase in pulse, and decrease in blood pressure.
A woman now becomes increasingly more sensitive to dehydration, and lack of proper fluid replacement can lead to dizziness, and fainting. These feelings of “light headedness” can be further aggravated by dropping blood sugars. Carrying around a supply of water, and quick snacks during the hot summer months is a good habit for the pregnant woman.
As the pregnancy continues, blood pressures continue to drop until weeks 32-34. At this gestational age the blood pressure reaches its lowest point, then pressures typically begin to rise slowly until delivery.
A common condition in the pregnant woman is anemia. Although the body will attempt to fill the new, and dilated vessels with blood, the maternal bone marrow can never generate enough red cells to meet the needs of the increasing blood volume required.
As a result, there is a normal “physiologic anemia” which all pregnant women experience. The body is able to “fill the blood vessels” with fluid, but can not quite meet the demands for red cell generation. This results in a dilutional effect with blood tests in pregnancy always showing an “anemia” when compared to non-pregnant values.
Shift in center of balance, backache, and tension:
As the weight of the fetus increases, the woman’s center of balance will be dramatically changed. The weight increasing in the front of the spine causes muscles along the lateral borders of the spine to contract to compensate, often leading to back pain, and back tension.
A gentle program of stretching of the back muscles (pre-natal yoga), and massage therapy can often help alleviate this discomfort. Activities that rely heavily on balance often must be decreased, or abandoned. This makes sports like tennis extremely difficult for pregnant women approaching the third trimester (6-9 months).
Vena Cava-sleeping and Yoga:
As the fetus grows, laying on the back for prolonged periods may compress the vena cava. As a Yoga Instructor, we must consider Vena Cava when putting pregnant women into Yoga. As a woman enters the last half (4-5-9 months) of her pregnancy, she will begin to feel increasingly more uncomfortable when laying on her back, or reclined without turning to the side.
The Vena Cava is the main vein that drains the entire lower half of the body. Anatomically, it lies just to the right of the midline….just on the right side of your spine. As the baby gets bigger the heavier uterus, lying flat on the Vena Cava, will obstruct flow up towards the heart.
The drainage of the lower half of the body becomes sluggish, which not only increases swelling of your ankles, feet, and legs, but will also impact on hemorrhoids as well. And decreased return of blood flow to the heart will cause hypotension (lowered blood pressure) down the line, and result in diminished arterial blood flow to the uterus, placenta, and baby.
Sometimes this hypotension is evident when a woman has an ultrasound, during which she lies flat. One of the symptoms of hypotension is nausea that will accompany the light-headedness. Laying on the back is the worst possible position in the third trimester (6-9 months). Laying on the right side is better than laying on your back, but laying on your left side is the best of all, because this is the position which will have the least amount of weight upon the Vena Cava.
There are many pregnancy complications that can dramatically effect the wisdom of certain activities during your pregnancy. Consult a physician before proceeding with any exertion if any of the following are present:
History of multiple pregnancy losses
History of incompetent cervix, or cerclage placement
History of small for gestational age babies
Pregnant women are advised to be careful during the first three months. Yoga asanas are good for increasing circulation, toning the pelvic region, and strengthening the spine, however, jumping around, and over exerting, is not advisable during these months, as there is a chance of miscarriage due to muscular weakness, and improper function of the placenta. During weeks 11-13 it is recommended to avoid any heat forming postures, or strenuous exercise.
Exercise enough to maintain your “well being”, but not so much so as to detract from normal fetal growth. The exact amount of activity tolerated by each maternal-fetal couple will vary tremendously.
An increase in estrogens during pregnancy help loosen the ligaments of the body. Women may find their ‘game’ or yoga practice significantly enhanced due to looseness, and increased flexibility. Be mindful during your practice to prevent injury.
Another good article “Fertility and Fish Oil“.