Microscopic examination of sperm

For human reproduction, fertility is a very important thing. For fertility, in addition to the eggs of female friends, the other indispensable thing is sperm. As the main member of life, many people are curious about sperm. You should know that in the male infertility examination, sperm examination is very important. This examination will be done with a microscope. So, what exactly is the examination? Let's learn about it together below.

(1) Sperm motility:

[Normal reference value] The lower limit of the reference value for sperm viability (spermatozoa with intact membrane) is 58%.

[Clinical significance]

Reduced sperm survival rate is an important cause of infertility.

(2) Sperm motility:

Sperm motility classification

① Forward movement (PR): sperm moves actively in a straight line or along a large circle, regardless of its speed;

② Non-forward motion (NP): All other forms of non-forward motion, such as small circular motion, where the tail force can hardly drive the head, or only tail swinging is observed;

③ Inactivity (IM): no exercise;

[Normal reference value] Total sperm motility (PR NP) ≥ 40% or progressive motility of sperm ≥ 32%.

(3) Sperm concentration:

[Normal reference value] The lower limit of the sperm concentration reference value is 15×106ml.

When the sperm count is less than 15×106ml, it is oligospermia. Endocrine factors, endocrine disorders in the human body, especially the hypothalamus, pituitary gland, testicles, the gonadal axis, system dysfunction, leading to testicular spermatogenesis disorders, will manifest as oligospermia or even azoospermia. For example, low gonadal hormones can cause small testicles and poor male characteristics. For example, increased prolactin can also cause oligospermia. Thyroid diseases, diabetes, etc., also have a great impact on the number of sperm.

(4) Sperm morphology:

[Normal reference value] Normal sperm is tadpole-like and consists of three parts: head, body and tail. The head is slightly flat, oval, with regular outline, clear apex, and the apex cap covers more than 1/3 of the head surface. There is a translucent area at the front end of the sperm head. The head is 3-5um long and 2-3um wide, with an aspect ratio of 1.5-2:1. The aspect ratio is one of the important data for judging whether the sperm morphology is normal. The middle section of the body is slender, less than 1/3 of the head width, with a straight and regular outline, in line with the longitudinal axis of the head, about 5-7um long and lum wide. The tail is slender, regular in appearance and not curled, and is generally 50-60um long. HE staining shows the apex to be light red, the nucleus is located at the base of the apex, purple-red, and the tail is light purple-red. Modified Papanicolaou staining shows that the apices are light green, the nuclei are purple-red, and the tails are green.

The lower limit of the reference value for normal sperm morphology is 4%

(5) Semen cell examination

[Normal reference value] White blood cells (WBC): <5/HP (high power field); Red blood cells (RBC): 0-occasionally/HP.