The dimensions and shape of the human vagina are of great importance in medicine and surgery ;  there appears to be no one way, however, to characterize the vagina's size and shape. Although the dimensions of the human vagina have not been the subject of intensive research to the same extent as research into human penis size ,  a number of research studies have been made of the dimensions of the human vagina. A study by Pendergrass et al. A second study by the same group showed significant variations in size and shape between the vaginas of women of different ethnic groups.
Oh no, there's been an error
There are racial differences in vaginas. FACT. – VAGINA BLOG
Methods: Eighty six PCOS women Rotterdam criteria and forty five matched ovulatory and normo-androgenic women were recruited. A detailed 2D and 3D trans-vaginal scan was carried out in early follicular phase D2-D5 in all patients. Results: Mean ovarian volume was Conclusion: 2D and 3D trans-vaginal scans are equally accurate for assessment of ovarian morphology.
Human vaginal size
In a boring, homogeneous world, guys everywhere would have the same hair, the same body, the same dick. And every woman would have the same shape, and their vaginas would be the same size and color. But figuring out who in your family tree you can thank or scream at for the size of your penis is far trickier.