Potential role for spermatozoa in repetition of miscarriage

Unfortunately, in their attempt to conceive a child, some people may be faced with recurrent pregnancy loss, also known as recurrent miscarriage. Defined as the consecutive loss of three or more pregnancies before 20 weeks of pregnancy, RPL affects about 1% of women.

Currently, there are only a handful of clinically accepted physiological causes of RPL. These include but are not limited to; parental chromosomal abnormalities, untreated hypothyroidism, uncontrolled diabetes mellitus, uterine anatomical abnormalities, immunological abnormalities and endocrine disorders. Unfortunately, not all RPLs fall into one of these categories and, according to the Miscarriage Association, more than half of the cases will remain unexplained.

Women and their partners often desperately seek answers about the cause of their losses. Channa Jayasena, MD, Ph.D., of Imperial College London, said: "The women involved are undergoing many tests to determine the cause, but many cases have no identified cause."

New research presented at the annual meeting of the Endocrine Society (ENDO 2019) examined the role of sperm DNA damage in the male partner of RPL. "We know that sperm play an important role in the formation of the placenta, which is essential for the survival of an unborn baby," added Jayasena, principal investigator. The results of the research are published in the journal Clinical chemistry.

The study aimed to determine whether male partners of women with RPL were more likely to experience damage to sperm DNA, known to negatively affect fertility. The researchers badyzed sperm from 50 healthy men versus sperm from 63 men whose partners had RPL.

"We used microscopy to check the function of sperm, luminol color change to measure the amount of oxidation in sperm and Halosperm kits to detect damage in sperm DNA," explains Jayasena.

The results showed that men whose female partners had experienced RPL had twice as much damage to sperm DNA as the control group of unaffected men, in addition to a multiplication by four of the amount of reactive oxygen species (ROS). ROS damage the DNA of cells such as spermatozoa.

Jayasena and his team hope their findings could pave the way for the development of new pharmaceutical agents for RA: "The first step in developing a drug to treat RA in men is to identify its cause. Our study suggests that fragmentation of sperm DNA and sperm ROS could be involved in RPL. The next step is to find ways to reduce the fragmentation of sperm DNA and sperm ROS, and then see if this can reduce the risk of RPL. "

These results certainly deserve to be explored on the ground, and it seems that couples facing AR are more willing to offer their help: "We were struck by the enthusiasm of men with the RA to participate in the study. and improve the treatment of future RPLs. In fact, it was much harder to recruit healthy volunteers, "says Jayasena.

Reference: Jayasena et al. 2019. Reduction of testicular steroidogenesis and increased oxidative sperm stress in male partners as new markers of recurrent miscarriage. Clinical chemistry. DOI: 10.1373 / clinchem.2018.289348.