Recurrent miscarriage might be linked to faulty sperm: Study

According to a recent study, recurrent miscarriage may be linked to the poor quality of a man's sperm.

As part of the study, the researchers investigated the sperm quality of 50 men whose partners had suffered three or more consecutive miscarriages.

Recurrent miscarriage affects around one in 50 couples in the UK and is defined as the consecutive loss of three or more pregnancies before 20 weeks gestation.

Until recently recurrent miscarriage was thought to be caused by health issues with the mother, such as infection or immune problems.

However, doctors are now realising that sperm health may also play a role in this complication. Channa Jayasena, lead author of the research said, "Traditionally doctors have focused attention on women when looking for the causes of recurrent miscarriage. The men's health - and the health of their sperm wasn't analysed."

"However, this research adds to a growing body of evidence that suggests sperm health dictates the health of a pregnancy. For instance, previous research suggests sperm has an important role in the formation of the placenta, which is crucial for oxygen and nutrient supply to the foetus," Jayasena explained.

As part of the study, the research team analysed sperm of 50 men whose partners have suffered from a recurrent miscarriage. They then compared the results to the sperm health of 60 male volunteers whose partners had not suffered a miscarriage.

The analysis revealed sperm from men with partners who had suffered recurrent miscarriage had two times more DNA damage compared to the other control group.

The research team suggests this DNA damage may be triggered by so-called reactive oxygen species.

There are molecules formed by cells in semen (the fluid that contains sperm cells) to protect sperm from bacteria and infection. However, in high enough concentrations the molecules can cause significant damage to sperm cells.

The results from the study revealed sperm from men whose partners had suffered miscarriage had a four-fold increase in the number of reactive oxygen species compared to the control group.

Jayasena explained: "Although none of the men in the trial had any ongoing infection such as chlamydia - which we know can affect sperm health - it is possible there may be other bacteria from previous infections lingering in the prostate gland, which makes semen. This may lead to permanently high levels of reactive oxygen species.