The quality of sperm is of great importance for the effectiveness of in vitro fertilization.
During a standard IVF procedure, one spermatozoid of the best quality penetrates the
ovum, and the remaining tens of thousands ensure the penetration of this one.
ICSI (intracytoplasmic sperm injection): If the number of spermatozoa is small or their
activity is reduced, the embryologist resorts to the ICSI procedure—sperm injection into
the cytoplasm of the egg cell. The manipulation is carried out at magnification by 400
times, with the help of holding and injection needles. For ICSI, the fastest
morphologically normal spermatozoid is selected. It is immobilized and placed into a
microneedle. Then while holding the egg on the micro-suction cup, an embryologist
pierces the egg shell with a micro-needle and injects the spermatozoid into it.
Initially, the ICSI method was introduced to treat the most severe cases of male
infertility, but it proved to be so effective that it is increasingly used as the main method
of fertilization without additional indications.
Indications for ICSI:
 a decreased number of spermatozoa
 reduced sperm motility
 numerous pathological forms of spermatozoa
 combined sperm pathology
 fertilization with spermatozoa thawed after freezing
 fertilization with oocytes thawed after freezing
 absence of spermatozoa in sperm (azoospermia), when spermatozoa are
retrieved surgically from a testicle (TESE) or epididymis (PESA)
 obtaining spermatozoa from urine in case of retrograde ejaculation
 immunological infertility (positive MAR test)
 fertilization failure after conventional IVF
IMSI: With male infertility and a considerable decrease in the number of spermatozoa
that have normal morphological characteristics, the search for a suitable spermatozoid
for fertilization grows much more difficult. In this case, IMSI technology (intracytoplasmic
injection of morphologically selected spermatozoa) is used—a relatively new technique
that allows choosing the best sperm cell at magnification by 6,600 times. This
magnification allows specialists to determine the smallest changes in the morphology of
spermatozoa.

Selection of spermatozoa at IMSI is a very long and laborious process. In particularly
difficult cases, the search for a normal spermatozoid can last several hours. The use of
IMSI reduces the risk of having a child with congenital malformations.
PICSI: In addition to the morphological structure, maturity of spermatozoa is important
for their selection for ICSI. If there are a lot of immature forms in sperm, it is necessary
to use the PICSI method (physiological intracytoplasmic sperm injection, physiological
ICSI), which allows choosing the best spermatozoid for ICSI taking into account its
physiological maturity.
The envelope surrounding the egg contains a natural hyaluronan biopolymer. In natural
conditions mature spermatozoa only come into contact with it as they have a complete
set of receptors necessary for fertilization. As a result, one of the mature spermatozoa
penetrates into the egg cell.
The ability of mature spermatozoa to get bound with hyaluronan is in the basis of the
PICSI method, which allows reconstructing the natural fertilization process as closely to
natural conditions as possible and predicting behavior of a spermatozoid during
fertilization.
PICSI makes use of special plates on the bottom of which this biopolymer is applied.
When on such a plate, spermatozoa get bound with hyaluronan. By the nature of the
bond, the embryologist can identify the most suitable spermatozoa for carrying out
PICSI. Later on, from the selected spermatozoa, the best ones can be chosen based on
their morphological characteristics.
Research has shown that when carrying out PICSI, bonds with hyaluronan are formed
by spermatozoa that have less DNA damage and fewer chromosomal abnormalities
than those selected on the basis of exclusively morphological characteristics. PICSI
gives the best quality of embryos, increases the likelihood of implantation, and reduces
the chances of abortion.
However, with “good” sperm, PICSI practically does not affect the result. In order to
understand whether PICSI is needed in a particular case, an HBA test (hyaluronan
binding assay) is carried out.
Indications for PICSI:
 a high level of DNA fragmentation
 poor quality of embryos in previous attempts
 repeated absence implantation in previous ART attempts
 repeated incidents of spontaneous abortions in previous ART attempts
 a low content of morphologically normal spermatozoa forms
 low fertilization after IVF or ICSI
 age of a woman > 38