External Conjugate Diameter Of the Pelvis - Pt/1

External Conjugate Diameter Of the Pelvis

This Measurement is taken with a pelvimeter, one point of which is placedon the spine of the last number vertebra, and the other on the front of the pubes. It shouldbe 7.5 inches.
It is not always easy to feel the spine  of the last lumbar vertebra. In case of doubt the position of the spine can be ascertained as follows. 

The position of the each posterior superior spine of the iliac bones can easlily  be determined if the woman stands up. 

A point 1.5 inches above the centre of a line joining these two iliac spines denotes the position of the spines are at thimes indicated  by dimples in the Skin.