Labour pain: correlations with menstrual pain and acute low-back pain before and during pregnancy

Abstract

Low-back pain is a major component of labour pain in a substantial number of women. The purpose of this study was to determine whether episodes of acute low-back pain prior to pregnancy is a predictor of low-back pain during labour. 114 women received the Short-Form McGill Pain Questionnaire (SF-MPQ) during labour and were asked to describe the pain separately for front and back contraction pain or continuous pain. The day after the birth of the child the women were interviewed to determine whether they had (a) a history of episodes of acute low-back pain before pregnancy, (b) low-back pain during pregnancy, and (c) low-back pain during menstruation. The results show that episodic low-back pain before pregnancy is not correlated with any aspect of labour pain. However, it is significantly correlated with episodes of low-back pain during pregnancy. In contrast, low-back pain during menstruation is significantly correlated with labour pain scores recorded for back and front contraction pain as well as for continuous back pain. The significant correlation of labour pain with back pain during menstruation suggests that both share a common underlying mechanism. Similarly, the correlation of low-back pain during pregnancy with episodes of acute low-back pain before pregnancy suggests that the strain on back muscles during pregnancy may activate the mechanisms that underlie the usual forms of low-back pain.