Sperm DNA Fragmentation Test
A standard semen analysis tells you how many sperm there are and how they move. A DNA fragmentation test tells you whether the genetic material inside them is intact.
What this test measures
The test reports a DNA fragmentation index (DFI): the percentage of sperm with broken or damaged DNA strands. Labs use assays such as SCSA, TUNEL, or Comet; the number is comparable within a method but not always across methods.
High fragmentation is linked to longer time to pregnancy, recurrent miscarriage, and lower success with IUI and IVF — even when the regular semen analysis is normal. It is most often ordered after unexplained infertility or repeated pregnancy loss.
Parameters reported
How to prepare
- Abstain 2–7 days. Long abstinence raises DNA fragmentation, so stay at the shorter end of the window if you can.
- Avoid fever, saunas, and hot tubs for the weeks before testing — heat drives fragmentation up temporarily.
- No lubricants or spermicide during collection; collect the whole sample.
- This test is run at a small number of specialty andrology labs. Check the lab's collection rules when you book.
- Bring your Hera lab order and a photo ID.
What happens at the lab
- Check in at the lab's front desk and hand over your Hera order. The lab may ask you to register as a patient — this takes a few minutes.
- You'll be given a sterile cup and a private room. Wash your hands, collect by masturbation, and note the exact time of collection on the label.
- Hand the sample back to staff. Analysis starts within an hour, so there's nothing else for you to do on site.
Getting your results
Turnaround depends on the assay and lab — confirm when you book.
As a rough guide with SCSA: under 15% is considered normal, 15–30% moderate, and over 30% high. Thresholds differ by method, so read the lab's own reference range.
Fragmentation responds to lifestyle changes (heat, smoking, varicocele repair, antioxidants) faster than count or morphology; a repeat test in 3 months shows whether a change worked.
Common questions
Who should get a sperm DNA fragmentation test?
Couples with unexplained infertility, recurrent miscarriage, or failed IUI/IVF cycles — especially when the standard semen analysis looks normal. Men with a varicocele, a history of high fever, or heavy heat exposure are also common candidates.
Is DNA fragmentation part of a regular semen analysis?
No. A standard semen analysis measures count, motility, morphology, and volume. DNA fragmentation is a separate assay and must be ordered on its own.
Can a high DFI be improved?
Often, yes. Reducing heat exposure, quitting smoking, treating a varicocele, and antioxidant supplementation have all been shown to lower DFI. Shorter abstinence before IVF collection can also help.
Do I need a doctor's order?
Yes — Hera provides a physician-signed order for the labs it lists. Availability is limited to specialty labs, so check the locations listed below.
Where to get it
Lab networks with listed locations that run this test through Hera.
This test is available at a small number of specialty labs. Search the full directory to see current locations.