The pain you feel in your pelvis during pregnancy can be quite uncomfortable! The pelvis is actually a ring structure with the pubic bone being a joint where the right and left sides join together. During pregnancy, your body releases several different hormones that can cause pain in this area.
Progesterone is made in large quantities during pregnancy and has many benefits. One of the most beneficial properties is that it helps thicken the lining of the uterus for implantation. Progesterone also relaxes smooth muscles and ligaments, thus calming the contractions of the uterus while the baby grows. A side effect of the relaxing nature of progesterone is constipation, since it also relaxes the muscles in the gut. Other hormones that may affect pubic bone pain include relaxin and prolactin.
Your body needs the pelvis to widen so that you can deliver the baby, but when the joint between the left and right pubic bones begin to loosen it can also become quite painful. The medical term for this condition is pubic symphysis diastasis (diastasis means separation), and it is simply the normal act of the pubic bone opening up a bit to allow the baby to pass through during labor and delivery. Without this loosening, it would be impossible to delivery the baby via the birth canal.
Some women will experience pain in the lower back or to either side when the pubic bone separation happens. Other women will simply feel pain in the pubic bone area. If you can no longer stand on one leg to put your pants on, have trouble separating your legs, or feel pain in your pubic bone, pubic symphysis diastasis may be the culprit. You should talk with your health care practitioner about this pain to confirm that you do not have pain caused by a bladder infection or any premature dilation.
You may get some relief from a warm compress being placed over the pubic bone, or with the permission of your doctor the use of an occasional Tylenol. If the pain is severe, you should discuss other treatment options with your health care practitioner.