Paternal factors

The paternal factors causing miscarriage include:

• chromosomal translocations in the father may result in abnormal gametes and so cause spontaneous abortions. About 1:10 of couples with a history of recurrent abortion will have one partner with a chromosomal abnormality.
  
  
• immunological factors: in some women who recurrently abort it has been shown that there is not the usual formation of maternal blocking antibodies in response to the husband's component of the foetal tissue antigens. This antibody response is necessary for the normal continuation of pregnancy and absence of this response is associated with the loss of an otherwise normal foetus. Some success has been claimed for infusing mothers with paternal lymphocytes before attempting a further pregnancy.
• increasing age: numerous studies have shown that advanced paternal age may increase the risk of spontaneous abortion (1).

Reference:

• (1) Kleinhaus K. Paternal Age and Spontaneous Abortion. Obstetrics & Gynecology 2006;108(2): 369-377