What Does
Sperm Motility Mean?
Sperm motility refers to the number of sperm that are moving. Sperm motility is measured during a semen analysis, which is typically performed on men undergoing fertility testing. Sperm need to be able to move forward in a straight line through the female reproductive tract to locate and then fertilize an egg.
An analysis of sperm motility can provide insight into how a man’s sperm moves, including their direction, speed, and endurance.
Asthenozoospermia or asthenospermia is the medical term for decreased sperm motility.
FertilitySmarts Explains Sperm Motility
In order to determine whether or not a man’s sperm is contributing to infertility, a semen analysis is performed. According to the World Health Organization (WHO), at least 40% of the sperm in an entire sample should be moving to be considered normal. This is called the total motile sperm count.
Sperm Motility Grading
In order to fertilize an egg, sperm must perform a very precise function: swim-up, quickly, with little deterrence. Sperm that do not swim straight, (non-progressive motile), are unlikely to reach an egg or fertilize the egg. Therefore, the type of movement is important. Progressive motility is the term for sperm that moves forward in a straight line and 32% of sperm should fall into this category.
The WHO grades motility on a scale from A to D:
- A: Forward, fast and in a straight line (the normal percentage is 12%)
- B: Forward, but in a curved or crooked line, or slowly
- C: Move their tails, but swim in a small circle or don’t move forward
- D: Don’t move at all
Grades C and D are considered poor.
Other Motility Conditions
Necrozoospermia is the medical term for a total absence of moving sperm. Sperm may be present, but may not be alive.
Treatment
What impacts sperm motility?
- Diet
- Smoking and drinking
- Genetic factors
- Diabetes
- Hypothyroidism
- Varicocele
- Infection
- Testicular cancer
Treatment options may include intrauterine insemination (IUI) in vitro fertilization or intracytoplasmic sperm injection (ICSI) with in vitro fertilization (IVF) where healthy, non-motile sperm is injected directly into an egg.