There have been rapid developments in microinjection since its first application in 1992. Despite its widespread use in male infertility, there is always concern about anomalies in resulting pregnancies.
These concerns are based on two main factors. The first is the unnatural structure of fertilization due to various procedures performed on male and female reproductive cells. The fact that the sperm that performs fertilization has not been naturally selected always raises a question mark. On the other hand, the needle used during the procedure causing a small injury to the wall of the female egg also raises doubts that problems may arise in these babies in the future.
The second reason lies in whether male infertility is hereditary or not. The development of microinjection has coincided with the progress of genetic research on male infertility. The question is whether the problem that arises can be passed on to a male child in cases of severe male infertility where there is a break in the short arm of the Y chromosome.
The anomaly rates generally reported in research do not differ significantly from those in pregnancies obtained naturally. Since many teams today prefer to systematically perform chromosomal analysis on microinjection pregnancies, comparing chromosomal anomaly rates with the general population is very difficult. Nevertheless, studies have shown no significant difference between the rates. In cases of severe male infertility not caused by obstruction, such as azoospermia (no sperm in semen) or the absence of congenital channels, the likelihood of chromosomal anomalies is high, and chromosomal analysis must be performed before microinjection in these cases.
In the short and medium-term follow-ups of children born after microinjection treatment, it has been found that there are no negative effects of the treatment. However, long-term follow-ups of these children are very difficult. In a study conducted in Belgium, 201 microinjection babies were followed for two years, and no difference was found between them and the general population.
Although there is no scientific evidence to cause concern about microinjection babies, there is uncertainty about problems or diseases that may arise in the long term in advanced ages.
Infertility Risk in male children
The idea that couples with Y chromosome problems causing infertility can pass on the problem to their male children is not directly related to the microinjection method but to the couple’s infertility problem. Since it has been found that this condition can also occur in some men with completely normal sperm parameters, there has been a debate in scientific circles about the role of the problem in infertility.
Although there are cases of male or female genetic infertility, it is impossible to determine the frequency of this type of infertility today. Broad epidemiological data suggest that genetic factors play a very small role in infertility. In conclusion, almost 10 years have passed since the birth of the first microinjection baby, and the data obtained generally indicate that this method does not carry a significant risk.
The long-term effectiveness of microinjection procedures carried out under unique circumstances, such as using immature sperm like testicular sperm or spermatids, is still in question.