SOURCES:

WebMD.com: "Normal Menstrual Cycle: When to Call a Doctor" 
National Institute of Child Health and Human Development (NIH): “Menstrual Irregularities.”
Merck.com: “Fibroids.”
Merck.com: “Endometriosis.”
U.S. National Library of Medicine: “Genetics Home Reference: von Willebrand Disease.”
Weill Cornell Vascular: “What Are Uterine Fibroids?”
MayoClinic.com: “Uterine Fibroids: Risk Factors.”
U.S. Department of Health and Human Services: “Bleeding Disorders.”
Womenshealth.gov web site: “Menstruation and the Menstrual Cycle.”
National Institute of Child Health and Human Development (NIH): “Menstrual Irregularities.”

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