Recurrent miscarriage is a clinical entity where female faces 3 or more consecutive pregnancy losses less than 20 wks of gestation. About 1% of couples are affected by recurrent miscarriages.  

What could be cause of recurrent miscarriage?

This is not a type of infertility but it definitely warrants the need of investigation and proper treatment institution. Few known causes of recurrent miscarriages are parental chromosomal abnormalities, untreated hypothyroidism, uncontrolled diabetes,certain  uterine abnormalities & immunological disorder like Antiphospholipid syndrome, thrombophilias. Most of the etiologies of recurrent miscarriage are treated.

Is recurrent miscarriage considered infertility?

Special reference to immunological & thrombotic etiologies. There are various immunological events that play their role from achieving pregnancy and containing thereof. If these mechanisms are altered then rejection of fetus occurs. Therapies like paternal leukocyte immunization ,Immunoglobulin, third party donor cell immunizations are also available.            

Thrombotic etiologies also forms a major proportion of these cases. Some of these are mutations in gene responsible for clotting factors. One special & common one is MTHFR gene mutation which is enzyme degrading folic acid in body. 

How common are recurrent miscarriages?                                                                                                                    

Once it is diagnosed it can be treated and pregnancy can be achieved & completed count any problem.