Attenuation of pregnancy-induced analgesia by hypogastric neurectomy in rats.

This study confirms previous observations of an increase in pain threshold prepartum followed by a decrease postpartum. Moreover hypogastric nerve transection significantly attenuated the analgesia of pregnancy by a factor of 5 but did not abolish it. Thus, the hypogastric nerve plays a major, but not exclusive, role in the analgesia of pregnancy.