Pregnant women commonly experience pelvic pressure, and the primary cause is the enlargement of the uterus. As the fetus gets bigger, so does the uterus, leading to pressure on the surrounding structures. The second major cause of pelvic pressure in pregnancy is the stretching of the various pelvic ligaments that suspend the female reproductive organs and keep pelvic bones together. Other causes of pelvic pain include nerve compression and diminished circulation.
A pregnant or gravid uterus reaches the level of the pubic bone by the 12th week of gestation. By the 20th week, it reaches the umbilicus, and by the 36th week, it reaches the lowermost portion of the sternal bone. As a consequence of fetal and uterine growth, the highest degree of pelvic pressure is experienced during the third trimester. Other consequences include the compression of nerves and diminished lymphatic and blood circulation to the lower extremities.
Another major cause of pelvic pressure in pregnancy is the softening and stretching of ligaments. Ligaments connect the pubic symphysis — the joint between the pubic bones — as well as the left and right sacroiliac joints. To accommodate the growth of the baby, the ligaments of the mother become more lax. One factor that causes this is the relaxin hormone, which also produces effects such as collagen remodeling and increased elasticity of the surrounding pelvic muscles, tendons, and tissues. A condition called pelvic girdle pain, also called pelvic joint syndrome, posterior pelvic pain, symphysis pubis dysfunction, or physiologic pelvic girdle relaxation, is rooted in ligamentous laxity and joint instability in pregnancy.
It is important to address pelvic pressure during pregnancy because it can significantly affect the woman's life. For instance, a pregnant woman may have to take a sick leave from 7 to 12 weeks because of pelvic girdle pain. Pelvic pressure may also lead to higher stress levels, anxiety, and depression. There are treatments to help relieve the symptoms.
Abdominal and back muscle stretching exercises, swimming, and walking all may help relieve the pressure and pain. A woman should try to maintain good posture as well. Some women benefit from placing warm and cold compresses on the areas of pressure. If the problem is not relieved by these interventions, the pregnant woman should speak to her healthcare provider.
