Abstract
Excessive relaxation of the pelvic joints during pregnancy has as its chief symptoms chronic backache and locomotor disturbances. Goldthwait and others have for long drawn attention to the frequent part played by softening of the sacro-iliac joint structures in the production of the common backache of pregnancy. The frequency of this symptom may be gauged by the fact that 114 women out of a successive series of 3,030 cases at the antenatal clinic, or 3.7%, suffered in such a degree as to lead them to call for treatment. In 69, or 60.5%, the pain commenced before the 28th week, whilst in the remaining 45 or 39.5%, it commenced later.