Pregnancies ending in miscarriage were found to have fathers whose sperm showed increased numbers of defective sperm as well as lower sperm counts. This was the conclusion in a 1962 research project conducted by the Department of Obstetrics and Gynecology at the Sabbatsberg Hospital in Stockholm, Sweden. Semen specimens were gathered from 201 men whose wives had experienced miscarriages in the second to third month of pregnancy or spontaneous abortions in the fourth to fifth month of pregnancy. Over half the research families had experienced two or more miscarriages. For comparison, sperm samples were taken from a control group of 116 husbands who had visited the hospital but whose wives had produced living normal children within two years. To insure similar parameters among participants, sperm samples were acquired by masturbation after an abstinence period of five days. Results of the two groups showed that sperm counts for the miscarriage/spontaneous abortion group was 110.2 million per cubic centimeter, while the sperm counts for the fathers of successful pregnancies was 138.7 million per cubic centimeter. The investigators classified this as "highly significant statistically." Of even more concern, it was found through microscopic examination of sperm samples that approximately 48% of the sperm were "abnormal" in the unsuccessful pregnancies while only 4% of the sperm were "abnormal" in the men who produced normal children.





Pregnancies ending in miscarriage are being found to be fathered by men with higher numbers of abnormal sperm (i.e. misshapen sperm heads, double tails, etc.). Abnormal sperm are also being found to occur more often in males exposed to chemicals during the two month sperm development period before conception.

In summary, the researchers stated;

"In the group of abortions (unsuccessful pregnancies) there was a highly significant increase in the percentage of abnormal spermatozoa as well as a highly significant decrease in the absolute number of normal spermatozoa. The conclusion is reached that defective semen may be an important factor in the etiology of abortions."


Drs. Mirjam Furuhjelm, Birgit Jonson, and C. Lagergren
Dept. of Obstetrics and Gynecology, Sabbatsberg Hospital, Karolinska Institute, Stockholm, Sweden
International Journal of Fertility

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