James Mich
Wed, Apr-09-08, 17:16
Obstet Gynecol. 2008 Apr;111(4):914-920
Racial Differences in Pelvic Anatomy by Magnetic
Resonance Imaging.
Handa VL, Lockhart ME, Fielding JR, Bradley CS, Brubaker L,
Cundiff GW, Ye W, Richter HE; for the Pelvic Floor
Disorders Network.
Department of Gynecology and Obstetrics, Johns Hopkins
University, Baltimore, Maryland; Department of Radiology,
University of Alabama at Birmingham, Birmingham, Alabama;
Department of Radiology, University of North Carolina,
Chapel Hill, North Carolina; Department of Obstetrics and
Gynecology, University of Iowa Carver College of Medicine,
Iowa City, Iowa; Department of Obstetrics and Gynecology and
Urology, Loyola University Medical Center, Maywood,
Illinois; University of British Columbia, Vancouver, British
Columbia, Canada; Department of Biostatistics, University of
Michigan, Ann Arbor, Michigan; and Department of Obstetrics
and Gynecology, University of Alaama at Birmingham,
Birmingham, Alabama.
OBJECTIVES: To use static and dynamic magnetic resonance
imaging (MRI) to compare dimensions of the bony pelvis and
soft tissue structures in a sample of African-American and
white women. METHODS: This study used data from 234
participants in the Childbirth and Pelvic Symptoms Imaging
Study, a cohort study of 104 primiparous women with an
obstetric anal sphincter tear, 94 who delivered vaginally
without a recognized anal sphincter tear and 36 who underwent
by cesarean delivery without labor. Race was self-reported. At
6-12 months postpartum, rapid acquisition T2-weighted pelvic
MRIs were obtained. Bony and soft tissue dimensions were
measured and compared between white and African-American
participants using analysis of variance, while controlling for
delivery type and age. RESULTS: The pelvic inlet was wider
among 178 white women than 56 African-American women
(10.7+/-0.7 cm compared with 10.0.+0.7 cm, P<.001). The outlet
was also wider (mean intertuberous diameter 12.3+/-1.0 cm
compared with 11.8+/-0.9 cm, P<.001). There were no
significant differences between racial groups in
interspinous diameter, angle of the subpubic arch,
anteroposterior conjugate, levator thickness, or levator
hiatus. In addition, among women who delivered vaginally
without a sphincter tear, African-American women had more
pelvic floor mobility than white women. This difference
was not observed among women who had sustained an
obstetric sphincter tear. CONCLUSION: White women have a
wider pelvic inlet, wider outlet, and shallower
anteroposterior outlet than African-American women. In
addition, after vaginal delivery, white women demonstrate
less pelvic floor mobility. These differences may
contribute to observed racial differences in obstetric
outcomes and to the development of pelvic floor disorders.
Racial Differences in Pelvic Anatomy by Magnetic
Resonance Imaging.
Handa VL, Lockhart ME, Fielding JR, Bradley CS, Brubaker L,
Cundiff GW, Ye W, Richter HE; for the Pelvic Floor
Disorders Network.
Department of Gynecology and Obstetrics, Johns Hopkins
University, Baltimore, Maryland; Department of Radiology,
University of Alabama at Birmingham, Birmingham, Alabama;
Department of Radiology, University of North Carolina,
Chapel Hill, North Carolina; Department of Obstetrics and
Gynecology, University of Iowa Carver College of Medicine,
Iowa City, Iowa; Department of Obstetrics and Gynecology and
Urology, Loyola University Medical Center, Maywood,
Illinois; University of British Columbia, Vancouver, British
Columbia, Canada; Department of Biostatistics, University of
Michigan, Ann Arbor, Michigan; and Department of Obstetrics
and Gynecology, University of Alaama at Birmingham,
Birmingham, Alabama.
OBJECTIVES: To use static and dynamic magnetic resonance
imaging (MRI) to compare dimensions of the bony pelvis and
soft tissue structures in a sample of African-American and
white women. METHODS: This study used data from 234
participants in the Childbirth and Pelvic Symptoms Imaging
Study, a cohort study of 104 primiparous women with an
obstetric anal sphincter tear, 94 who delivered vaginally
without a recognized anal sphincter tear and 36 who underwent
by cesarean delivery without labor. Race was self-reported. At
6-12 months postpartum, rapid acquisition T2-weighted pelvic
MRIs were obtained. Bony and soft tissue dimensions were
measured and compared between white and African-American
participants using analysis of variance, while controlling for
delivery type and age. RESULTS: The pelvic inlet was wider
among 178 white women than 56 African-American women
(10.7+/-0.7 cm compared with 10.0.+0.7 cm, P<.001). The outlet
was also wider (mean intertuberous diameter 12.3+/-1.0 cm
compared with 11.8+/-0.9 cm, P<.001). There were no
significant differences between racial groups in
interspinous diameter, angle of the subpubic arch,
anteroposterior conjugate, levator thickness, or levator
hiatus. In addition, among women who delivered vaginally
without a sphincter tear, African-American women had more
pelvic floor mobility than white women. This difference
was not observed among women who had sustained an
obstetric sphincter tear. CONCLUSION: White women have a
wider pelvic inlet, wider outlet, and shallower
anteroposterior outlet than African-American women. In
addition, after vaginal delivery, white women demonstrate
less pelvic floor mobility. These differences may
contribute to observed racial differences in obstetric
outcomes and to the development of pelvic floor disorders.