Sperm telomere length is positively associated with the quality of early embryonic development

Study question: What is the relationship between telomere length in sperm and early embryonic development in in vitro fertilization (IVF)?

Summary answer: Sperm telomere length (STL) is positively associated with embryo quality in IVF.

What is known already: Previous studies have shown that STL differs among human males.

Study design, size, duration: In order to determine the associations between STL, fertilization laboratory parameters and clinical pregnancy in IVF, 418 couples were recruited from August 2013 to August 2014.

Materials, setting, methods: We collected semen samples and used quantitative PCR technique to detect the mean STL for each patient. These data were compared with the IVF outcomes.

Main results and the role of chance: The mean STL was positively correlated with the age of patient (rP = 0.100; P = 0.041) and total sperm count/ejaculate (rp = 0.28; P < 0.001). Analysis of the age-adjusted mean STL in relation to the male patient's paternal and maternal ages at the time of his conception showed significant positive relationships between STL and both paternal (r = 0.16; P = 0.003) and maternal (r = 0.19; P < 0.001) ages at the time of conception. In addition, significant correlations were found between STL and good quality embryo (regression coefficient: 1.63; P < 0.001) and transplantable embryo rates (regression coefficient: 1.57; P < 0.001), but clinical pregnancy rates were not affected (odds ratio = 1.00 [95% CI: 0.93-1.07]; P = 0.90).

Limitations, reasons for caution: This study showed that STL was positively associated with embryo quality in IVF. Additional studies are needed to confirm these observations.

Wider implication of the findings: STL has the potential to be used as a marker for the prediction of embryonic quality.

Study funding/competing interests: This work was supported by the National Natural Science Foundation of China (Grants 31271605 and 31471404), and the National Science Foundation for Young Scientists of China (Grant 31401274), and Science Foundation of First Affiliated Hospital of Zhengzhou University for Yong Scientists. The authors have declared that no competing interests exist.