Endocrinological and Environmental Causes of Recurrent Miscarriage: A Review

Early pregnancy loss is perhaps the most common obstetric complication, occurring in over two-thirds of human conceptions. Approximately 15 – 20% of all clinically recognized pregnancies will end in a miscarriage. Approximately, 1% of all women trying to conceive have recurrent miscarriage, defined as three previous miscarriages. Despite thorough examinations to exclude several well-known etiologic factors, the cause for recurrent spontaneous abortion can often not be found in almost 50% of cases In addition to genetic or auto-immune diseases, endocrine dysfunction and metabolic disorders have been implicated. The purpose of this review is to update potential endocrinological causes of RM including thyroid disease, diabetes mellitus, hyperprolactinemia and polycystic ovarian syndrome. Also, obesity, hyperandrogenism, luteal phase defects and environmental, occupational or personal habits, such as cigarette smoking or alcohol consumption, are assessed as potential etiologies of recurrent miscarriage.