Does DNA damage in sperm contribute to infertility?

This article reviewed the impact of sperm DNA fragmentation (SDF) on male fertility. The authors concluded that SDF is a marker of male infertility.

During conception, sperm deliver DNA (genetic material) that becomes part of the embryo. Breaks in DNA produce small pieces called fragments. This is called SDF. Studies suggest SDF reduces the chances of conception. SDF may also be related to genetic mutations in the offspring. 

SDF testing can measure what percentage of sperm have SDF. It is not clear how SDF testing impacts infertility treatment.

SDF testing is recommended for couples with unexplained infertility or who have two or more miscarriages. Testing is also recommended for men with risk factors of SDF. These include genital infections, advanced age, varicoceles (varicose veins in the scrotum), or past treatments for cancer.

This article looked at the results of 28 studies. These studies included 2883 men with infertility and 1294 men without infertility. 52% of men seeking infertility treatment had more than 20% SDF. In couples with over 30% SDF, natural conception was very rare.

There are different treatments for couples experiencing infertility. Ater direct sperm injection into the uterus, couples with SDF had 66% lower pregnancy rates. The chance of live birth was also significantly lower.

In vitro fertilization and direct sperm injection (into an egg; ICSI) are other options. The chance of pregnancy after these procedures was 19% lower for couples with high SDF. Using testicular sperm during ICSI significantly increased pregnancy rates for men with high SDF.

Men who eat diets high in fish, whole grains, and vegetables have significantly lower SDF than men who eat diets high in red meat, processed food, and sweets. One study found that six months of daily yoga and meditation significantly reduced SDF. Another study found that treatment with FSH (a hormone needed for sperm development) significantly reduced SDF by 35%. 

This study found that SDF is a meaningful measure of male infertility. The authors suggest that more research is needed to determine what treatments for SDF may help improve fertility outcomes.

There is more than one method to measure SDF. The SDF test used in this study typically shows higher values than other tests. More studies are needed to confirm these results.

If your partner has had more than two miscarriages or you have varicoceles (large veins in the scrotum), genital infections, or a history of cancer, talk to your doctor about SDF testing.