Deformities of the female pelvis related to severe rickets impair normal childbirth, which leads to higher mortality of the infant, mother, or both. Vitamin D deficiency is most common in regions with low sunlight, especially in the winter.[71] Chronic deficiencies in vitamin D may also be linked with breast, prostate, colon, ovarian, and possibly other types of cancers.[8][72][73][74] The relationship between cardiovascular disease and vitamin D deficiency also suggest link between health of cardiac and smooth muscle.[75][76] Low vitamin D levels have also been linked to impaired immune system and brain functions.[14][77][78] In addition, recent studies have linked vitamin D deficiency to autoimmune diseases, hypertension, multiple sclerosis, diabetes, and incidence of memory loss.