Which of the following is the shoest pelvic diameter?
Obstetric conjugate is the shoest diameter of the pelvic inlet. It measures the distance between the promontory of the sacrum and the symphysis pubis. Normally, it measures 10 cm or more. This cannot be measured directly by examining, it is calculated by subtracting 1.5 to 2 cm from the diagonal conjugate diameter. Diagonal conjugate is determined by measuring the distance from the lower margin of the symphysis to the sacral promontory. The four diameters of the pelvic inlet are: True conjugate diameter Transverse diameter Oblique conjugate diameter Diagonal conjugate diameter Ref: Cunningham F.G., Leveno K.J., Bloom S.L., Hauth J.C., Rouse D.J., Spong C.Y. (2010). Chapter 2. Maternal Anatomy. In F.G. Cunningham, K.J. Leveno, S.L. Bloom, J.C. Hauth, D.J. Rouse, C.Y. Spong (Eds), Williams Obstetrics, 23e.
Diagonal conjugate
Obstetric conjugate
True conjugate
All are equal