In medicine, anovulation is absence of ovulation when it would be normally expected (in a post-menarchal, premenopausal woman). Causes Anovulation can result from a variety of factors: Taking birth control pills Stress, new environment Chronic mental illness, such as depression Chronic physical illness, such as inflammatory bowel disease, poorly controlled diabetes, tuberculosis, or anemia Undernutrition, specific nutrient deficiencies, inadequate body fat Prolonged or continuous physical… (More on Anovulation)