To compare pelvic anatomy, using magnetic resonance imaging, between postpartum women with or without pelvic floor disorders. We measured postpartum bony and soft tissue pelvic dimensions in 246 primiparas, 6-12-months postpartum. Anatomy was compared between women with and without urinary or fecal incontinence, or pelvic organ prolapse; P < 0.01 was considered statistically significant. A deeper sacral hollow was significantly associated with fecal incontinence (P = 0.005). Urinary incontinence was marginally associated with a wider intertuberous diameter (P = 0.017) and pelvic arch (P = 0.017). There were no significant differences in pelvimetry measures between women with and without prolapse (e.g., vaginal or cervical descent to or beyond the hymen). We did not detect meaningful differences in soft tissue dimensions for women with and without these pelvic floor disorders. Dimensions of the bony pelvis do not differ substantially between primiparous women with and without postpartum urinary incontinence, fecal incontinence and prolapse.