[Epidemiology and pathophysiology of post-pregnancy osteoporosis.]

Post-pregnancy osteoporosis is a rare condition with little known pathophysiology. Most cases are diagnosed in the late stage of pregnancy or in the post partum while breastfeeding, particularly in first pregnancy. Non-traumatic vertebral fragility fractures are most commonly observed and characterized by prolonged severe pain and functional limitations. Conventional radiography will confirm the fracture in most cases, and magnetic resonance, which can be safely used during pregnancy, is effective in detecting vertebral fractures and bone marrow edema. It is important to exclude secondary osteoporosis, e.g. endocrine diseases, chronic liver and kidney diseases, autoimmune diseases, genetic diseases, drugs and malignant tumors. The prevalence of post-pregnancy osteoporosis is unknown, and may be estimated more than 3 for every ten thousand pregnant women. The pathophysiology of post-pregnancy osteoporosis is also unknown. The physiological bone resorption during reproduction does not normally cause fracture;instead, women who do fracture may be more likely to have additional secondary causes of bone loss and fragility, e.g. low body weight, low peak bone mass, malnutrition and heredity.