Can Males With Klinefelter's Syndrome Be A Father?

Klinefelter's syndrome is a chromosomal numerical disorder where the chromosomal structure is 47,XXY, with an additional X chromosome, instead of the normal 46,XY. Before the advent of ICSI treatment, males with the Klinefelter syndrome were given no chance of having a child, with Micro-TESE sperms are found in the testicular tissue and used for fertilizing the spouse’s egg by ICSI, allowing them to have a child. I would like to discuss two of our articles which report on our results with Klinefelter patients:

Are there any predicting markers for sperm recovery success by micro-TESE in men with Klinefelter syndrome?

In 2006, we found sperms by Micro-TESE in the testicular tissue of 42 out of 74 (56.7%) azoospermic patients with Klinefelter syndrome. We have found that FSH, LH, total testosterone, and testicle size did not affect the probability of finding sperms, however, age did make a significant difference. The success rate of finding sperms by Micro-TESE was higher in males aged younger than 30 years vs those older than 30 years of age. At the time when this article was published, we showed in another study in Japan that age was a strong determinant of finding sperms by Micro-TESE in the testicular tissue of males with Klinefelter syndrome.

Is there a difference between men with Klinefelter syndrome and azoospermic men with normal chromosomal structure, in sperm recovery by micro-TESE and ICSI results?

A study we had conducted in 487 males with azoospermia due to sperm production impairment who sought to have a child was published in Fertility and Sterility in April 2011. In that study, we divided male subjects with sperm production impairment into two groups and investigated the differences between the two groups in terms of the presence of sperms and ICSI results. 106 azoospermic males with Klinefelter syndrome in the first group and 379 azoospermic males with a normal chromosomal structure in the second group underwent Micro-TESE surgery to harvest sperms on the day of harvesting eggs.

As a result of the Micro-TESE operation, sperms were successfully harvested from the testicular tissue of 50 (47%) of the males with Klinefelter syndrome and 188 (50%) of the azoospermic males with normal chromosomal structure. Statistical analyses showed that a significant difference did not exist between the two groups. Based on a comparison of ages of Klinefelter males with or without successful sperm recovery, those with harvested sperms were significantly younger. In the other group of azoospermic males with normal chromosomal structure, the age of males was not a significant determinant between males with or without harvested sperms. After our 2006 study in 74 Klinefelter males which showed that age was a strong determinant, this study of 106 cases substantially underlined our previous findings.

Can Klinefelter males have children?

The ICSI results were no less surprising than the success rates in finding sperms. After injecting the eggs harvested from each of the two groups into the eggs of their spouses, the fertilizing ability of sperms harvested from males without a chromosomal structure disorder was superior to that of sperms harvested from males with a chromosomal structure disorder. However, the difference between pregnancy rates and live birth rates was not significant. Based on the miscarriage rates, the data showed similar results. Karyotype analysis of 21 out of 29 infants born from sperms harvested from men with the Klinefelter syndrome showed normal chromosomal structure.

As a summary of the findings of this study; it was previously believed that the probability of finding sperms in men with Klinefelter’s syndrome in the testicles was very low, and even if sperms were actually found, impregnation was unlikely; and even in that case, the children would most likely inherit the chromosomal structure disorder. Our study has refuted these misconceptions and showed that man with Klinefelter’s syndrome had the same probability of harvesting sperms and having a child as other azoospermic males. This study of 106 subjects is one of the largest studies of its kind in men with Klinefelter's syndrome in the medical literature.

Doç. Dr. Emre Bakırcıoğlu
Doç. Dr. Emre Bakırcıoğlu

Urology Specialist Assoc. Prof. Dr. Emre Bakircioglu.