P-022 Klinefelter syndrome couples are expected higher live birth rates than unexplained NOA couples after ICSI with testicular spermatozoa
Authors: Lee Y , Mizuta S , Matsubayashi H , Yamaguchi K , Takeuchi T , Ishikawa T 
Published: July 2024

Abstract

Study question
What are sperm retrieval rates (SRR) by microdissection TESE (micro TESE), fertilization rates, and pre- and post- implantation development in Klinefelter syndrome (KS) couples?

Summary answer
In KS couples, SRR, clinical pregnancy rates (CPR) per embryo transfer (ET), and live birth rates (LBR) per patient were higher than unexplained NOA couples.

What is known already
Micro TESE, in combination with ICSI, is presently used to treat infertility in cases of NOA including KS, which is the most common sex-chromosome disorder among infertile males, with a prevalence of 1 in 660 men and is a frequent cause of hypogonadism and infertility. There were few reports regarding ICSI outcomes in the couples of KS. The aim of this study is to assess the prevalence and the significance including SRR by micro TESE of ICSI outcomes with embryonic development in KS couples.

Study design, size, duration
A retrospective study was conducted in 212 patients with non-mosaic KS and 963 unexplained NOA patients with 46, XY without past history (unexplained NOA; not including after orchidopexy, KS, cryptozoospermia, post chemotherapy, mumps orchitis, etc) who underwent micro TESE and ICSI with fresh or cryopreserved testicular spermatozoa for their wives between September 2013 to November 2023.

Participants/materials, setting, methods
A total of 2204 azoospermic patients were examined for chromosomal analysis. We evaluated SRR of microdissection TESE, two pronuclei (2PN) rates, blastocyst development rates, good-quality blastocyst (Grade 3BB and above on day 5 by the Gardner scoring) rates, CPR per ET, and LBR per couple patient who underwent micro TESE. We did not undergo preoperative hormonal therapy for KS patients. Statistical analysis was performed using unpaired t-tests and chi-squared tests.

Main results and the role of chance
We identified 212 KS out of 2204 azoospermic patients (9.6%). SRR of the first attempt micro TESE in KS (91/175=52.0%) was significantly higher than unexplained NOA (166/768=21.6%) (p &lt; 0.001). 2PN, blastocysts development, and good-quality blastocysts rates were 49.2%, 42.9%, 16.9% in KS and 50.8, 45.8%, 21.0% in unexplained NOA respectively. Only good-quality blastocysts rate of KS was significantly lower than that of unexplained NOA (p &lt; 0.01). Taking into account deflection of wives age, each result was calculated at their age 38 or under, but they were the same. CPR and LBR per ET in KS (42.6%, 30.4%) were significantly higher than unexplained NOA (33.1%, 23.7%) (p &lt; 0.01, p &lt; 0.05). The couples were 26.4% (56/212) in KS and 12.0% (116/963) in unexplained NOA (p &lt; 0.001) who have given birth or ongoing pregnancy up to now after underwent micro TESE. That is, KS couples were significantly easier to give birth than unexplained NOA. Rates of congenital disorders had no significant difference between KS and unexplained NOA.

Limitations, reasons for caution
We did not show the data using ejaculated sperm with KS. The natal outcomes and development of these children has not been fully investigated, long-term follow-up of babies of the KS couples is needed.

Wider implications of the findings
Micro TESE is particularly helpful for KS cases, but embryonic development depend on the quality of spermatozoa. However, if a blastocyst can be obtained, the expectation of having a child is considered to be high. These results were shown to be useful in informing azoospermic couples undergoing micro TESE.

Trial registration number
not applicable