Influence of deoxyribonucleic acid damage on fertilization and pregnancy

Henkel, Ralf; Hajimohammad, Marjam; Stalf, Thomas; Hoogendijk, Christiaan; Mehnert, Claas; Menkveld, Roelof; Gips, Holger; Schill, Wolf-Bernhard; Kruger, Thinus F

doi:10.1016/j.fertnstert.2003.09.044

« Previous Next »Fertility and Sterility
Volume 81, Issue 4 , Pages 965-972, April 2004

Influence of deoxyribonucleic acid damage on fertilization and pregnancy☆

Ralf Henkel, Ph.D.
- Center for Dermatology and Andrology, Justus Liebig University, Giessen, Germany
- Reprint requests: Ralf Henkel, Ph.D., Center for Dermatology and Andrology, Gaffkystrasse 14, D-35385 Giessen, Germany (FAX: 49-641-9943368).
Marjam Hajimohammad
- Center for Dermatology and Andrology, Justus Liebig University, Giessen, Germany
Thomas Stalf, Ph.D.
- Institute for Reproductive Medicine, Giessen, Germany
Christiaan Hoogendijk, M.Sc.
- Reproductive Biology Unit, Tygerberg Hospital and University of Stellenbosch, Tygerberg, South Africa
Claas Mehnert, M.Sc.
- Institute for Reproductive Medicine, Giessen, Germany
Roelof Menkveld, Ph.D.
- Reproductive Biology Unit, Tygerberg Hospital and University of Stellenbosch, Tygerberg, South Africa
Holger Gips, M.D.
- Institute for Reproductive Medicine, Giessen, Germany
Wolf-Bernhard Schill, M.D.
- Center for Dermatology and Andrology, Justus Liebig University, Giessen, Germany
Thinus F Kruger, M.D.
- Reproductive Biology Unit, Tygerberg Hospital and University of Stellenbosch, Tygerberg, South Africa

Received 1 May 2003; received in revised form 3 September 2003; accepted 3 September 2003.

Abstract

Objective

To investigate sperm DNA damage in relation to fertilization and pregnancy.

Design

Prospective study.

Setting

The Institute of Reproductive Medicine, Giessen, Germany.

Patient(s)

Semen collected from 249 patients attending the IVF program.

Main outcome measure(s)

The percentage of terminal deoxynucleotidyl transferase-mediated dUDP nick-end labeling- (TUNEL-), Fas-, and annexin-V-positive sperm and the proportion of green-fluorescing sperm in the acridine orange stain was determined and correlated with sperm concentration, motility, fertilization, and pregnancy.

Result(s)

Significant correlations with the concentration of motile sperm were only found for the acridine orange stain (before and after sperm separation) and for the TUNEL assay (after sperm separation). Moreover, patients whose sperm had a high percentage of DNA fragmentations showed significantly lower pregnancy rates (TUNEL assay: 19.05% vs. 34.65%; acridine orange stain: 24.58% vs. 37.93%). The apoptosis parameters (annexin V binding and Fas expression) showed no statistically significant differences.

Conclusions

Our data clearly demonstrate that DNA fragmentation, as determined by the TUNEL assay, is predictive for pregnancy in IVF. This implies that spermatozoa with DNA fragmentation can still fertilize an oocyte but that when paternal genes are “switched on,” further embryonic development stops, resulting in failed pregnancy. It seems that, at least in the patients we analyzed, apoptosis in the sperm does not play a role for fertilization. This would imply that DNA fragmentation in human spermatozoa is caused by external factors, such as reactive oxygen species, rather than by apoptosis.

Keywords: DNA damage, apoptosis, DNA fragmentation, DNA integrity, pregnancy failure, human spermatozoa