My fiance had a semen analysis that showed he has abnormal sperm morphology. What does this mean?

Answers from Landon Trost, M.D.

Sperm morphology — the size and shape of sperm — is one factor that's examined as part of a semen analysis to evaluate male infertility. Sperm morphology results are reported as the percentage of sperm that appear normal when semen is viewed under a microscope.

Normal sperm have an oval head with a long tail. Abnormal sperm have head or tail defects — such as a large or misshapen head or a crooked or double tail. These defects might affect the ability of the sperm to reach and penetrate an egg. However, having a large percentage of misshapen sperm isn't uncommon. In addition, morphology alone doesn't indicate if you are fertile or not. A typical semen analysis also assesses:

  • Semen volume
  • Total sperm number
  • Sperm concentration
  • Vitality (percent alive)
  • Movement (motility)

An abnormal semen analysis also doesn't mean that you are infertile. Many men with low semen analysis values can still father children — it just might take longer. If you and your partner aren't able to conceive through sexual intercourse, assisted reproductive technology such as in vitro fertilization might be an option.


Landon Trost, M.D.

May 20, 2015 See more Expert Answers