The geometry of bony pelvis differs significantly between males and females – the phenomena caused by adaptation to the obstetric demands. Females have a relatively larger and rounder pelvic cavity, a shorter and more posteriorly projecting sacrum, a wider subpubic angle, and smaller acetabula with a larger distance between them1,2. It is, however, worth mentioning that in real-life, the gender dimorphism of the pelvis is not as evident as generally described3,4.
The images presented here demonstrates the classically dimorphic pelvises with the length dimensions based on multiple sources of evidence5–10. The range of reference values reflects rather "average," than "the normal" range, or, by use of statistical terms — rather 95% Confidence Interval, than the double Standard Deviation.
1 Fischer B, Mitteroecker P. Allometry and Sexual Dimorphism in the Human Pelvis. Rosenberg KR, Desilva JM, eds. Anat Rec. 2017;300(4):698-705.
2 Patriquin ML, Steyn M, Loth SR. Metric analysis of sex differences in South African black and white pelves. Forensic Science International. 2005;147(2-3):119-127.
3 Delprete H. Pelvic Inlet Shape Is Not as Dimorphic as Previously Suggested. Rosenberg KR, Desilva JM, eds. Anat Rec (Hoboken). 2017;300(4):706-715.
4 Vacca E, Di Vella G. Metric characterization of the human coxal bone on a recent Italian sample and multivariate discriminant analysis to determine sex. Forensic Science International. 2012;222(1-3):401.
5 Siccardi MA, Imonugo O, Valle C. Anatomy, Abdomen and Pelvis, Pelvic Inlet. January 2020.
6 Salk I, Cetin A, Salk S, Cetin M. Pelvimetry by Three-Dimensional Computed Tomography in Non-Pregnant Multiparous Women Who Delivered Vaginally. Pol J Radiol. 2016;81:219-227.
7 Keller TM, Rake A, Michel SCA, et al. Obstetric MR pelvimetry: reference values and evaluation of inter- and intraobserver error and intraindividual variability. Radiology. 2003;227(1):37-43.
8 Buli HC. Pelvimetry in Obstetrics. Postgraduate Medical Journal. 1949;25(285):310-318.
9 Liao KD, Yu YH, Li YG, et al. Three-dimensional magnetic resonance pelvimetry — A new technique for evaluating the female pelvis in pregnancy. European Journal of Radiology. 2018;102:208-212.
10 Kolesova O, Kolesovs A, Vetra J. Age-related trends of lesser pelvic architecture in females and males: a computed tomography pelvimetry study. Anat Cell Biol. 2017;50(4):265–10.