What do test results mean?
Having a large number of abnormally formed sperm in a sample and a low NF score are signs of a condition called teratozoospermia.
The precise range can vary, but typically a normal or healthy sperm morphology range is between 4 and 14 percent NF. A score below 4 percent may mean it takes longer than normal to achieve pregnancy.
A result of 0 percent NF usually means in vitro fertilization (IVF) may be necessary for conception. IVF involves the collection of an egg and sperm sample to be combined in a petri dish in the hopes of fertilization.
The criteria for sperm morphology was developed less than a decade ago, so there are still a lot of discrepancies in how the test is conducted and results interpreted.
It is also important to remember that sperm that is abnormal in size or shape usually still carries healthy genetic material. Many fertile men have a high percentage of abnormal sperm.
Most of the studies that have found a link between low sperm morphology scores and reduced fertility rates used IVF subjects and settings.
A man whose NF is score below 4 percent should talk to his doctor to rule out the potential for complications and additional health conditions.
Doctors specializing in male infertility may help identify a cause for abnormal morphology rates, and in some cases, recommend a course of treatment to improve sperm quality
Other fertility factors
Sperm morphology tests are only one component of a general semen analysis.
Different laboratories, medical practices, and doctors may include different processes as part of their sperm analysis testing.
Other factors and hormones levels typically assessed during semen analysis include:
- Vitality, or the percentage of living sperm
- Motility, or general movement patterns and moving ability of sperm
- The concentration of the semen
- The total fluid volume of semen
- Liquefaction, or how quickly semen liquefies to facilitate sperm travel
- Total sperm number or count
- Semen thickness (viscosity)
- The appearance of the semen
- Semen pH
- Other foreign cells in semen, most often bacteria
- Testosterone
- Sex hormone-binding globulin (SHBG)
- Follicle stimulating hormone (FSH)
- Prolactin
- Estradiol
- DNA form and function
The presence of additional body cells in semen, such as epithelial cells (cells from the male ducts), immune cells such as leukocytes (white blood cells), and macrophages (scavenger immune cells) may also be assessed.