Pregnancy is not an illness and women who are having a trouble-free pregnancy can practice yoga with a few modifications. Pregnant women should ensure that their yoga teacher is aware of their condition and knows how to teach pregnancy modifications.What is possible for each woman is individual, depending on their strength and fitness levels before they fell pregnant. A basic rule of avoiding anything that causes undue discomfort or pain in the pelvic region should be followed.
Most doctors also do not advocate hot yoga, although many Bikram practitioners who have an established practice do continue throughout their pregnancy and report no bad effects. This is an individual choice, but again, the rule of avoiding anything that causes discomfort should be applied. You should definitely not start hot yoga as a new practice when pregnant. Saunas and hot tubs should also be avoided.
Lying on the back for longer than 3 minutes is also not recommended, as it ends to interfere with the blood supply to the Uterus. Savasana should be taken lying on the side, instead.
A major concern with pregnancy and yoga is that women have high levels of hormones that relax the ligaments, especially in the pelvic area and they become prone to Sacroiliac problems and should be very careful of overstretching or of practicing asanas that stress the pelvic area, like Hanumanasana or Virabhadrasana, especially if they have a past history of Sacroiliac dysfunction. Lower back pain in pregnancy is mainly caused by the shifting of the body’s centre of gravity as the baby grows, the pelvis tilts forward and the curvature of the lumbar spine is exaggerated. Larger, heavier breasts also tend to cause a rounding of the upper back.
High levels of hormones in the last trimester can also leave women feeling clumsy and uncoordinated and practicing asanas with the back against a wall for support is a safer option.
General recommendations for asana practice are to avoid strong twists, inversions and backbending of all kinds- the stomach muscles are in a stretched state, stretching them further in backbending can lead to tearing of the abdominal wall and the development of hernias. Practicing Mula Bandha is very beneficial, as well as Utkatasana with the feet hip-width apart. Marjarasana is helpful for relieving lower back pain and should be practiced regularly.
De Franca, 1996, Pelvic Locomotor Dysfunction
Kim, 2004, Ultimate Flexibility
Robinson, Knox, 2004, Pilates Pregnancy Book