Journal of Infertility and Reproductive Biology

Published date: Jun 20 2025

Journal Title: Journal of Infertility and Reproductive Biology

Issue title: Journal of Infertility and Reproductive Biology: Volume 13, Issue 2

Pages: 89 - 96

DOI: 10.18502/jirb.v13i2.18627

Adithya R Pillaiadi.r.pillai.research@gmail.comCytogenetics Division, Central Research Laboratory, Believers Church Medical College Hospital, Kuttapuzha P.O, Thiruvalla-689103, Kerala

Aaron M Thomasaaronmthomas2004@gmail.comCytogenetics Division, Central Research Laboratory, Believers Church Medical College Hospital, Kuttapuzha P.O, Thiruvalla-689103, Kerala

Melita Mary Georgemelitamaryg@gmail.comCytogenetics Division, Central Research Laboratory, Believers Church Medical College Hospital, Kuttapuzha P.O, Thiruvalla-689103, Kerala

Nevil George Ninannevil.ninan@bscbfh.christuniversity.inCytogenetics Division, Central Research Laboratory, Believers Church Medical College Hospital, Kuttapuzha P.O, Thiruvalla-689103, Kerala

Sandra Antonysandraantony349@gmail.comCytogenetics Division, Central Research Laboratory, Believers Church Medical College Hospital, Kuttapuzha P.O, Thiruvalla-689103, Kerala

Merlyn Princemerlynvmankottayil@gmail.comCytogenetics Division, Central Research Laboratory, Believers Church Medical College Hospital, Kuttapuzha P.O, Thiruvalla-689103, Kerala

Angela Johnangelaj2899@gmail.comCytogenetics Division, Central Research Laboratory, Believers Church Medical College Hospital, Kuttapuzha P.O, Thiruvalla-689103, Kerala

Anjali Anne Jacobanjalijacob1974@gmail.comDepartment of Microbiology, Believers Church Medical College Hospital, Kuttapuzha P.O, Thiruvalla-689103, Kerala

Riju Mathewlabmanager@bcmch.orgDepartment of Biochemistry, Believers Church Medical College Hospital, Kuttapuzha P.O, Thiruvalla-689103, Kerala

Unexplained infertility (UI) is an ambiguous condition that afflicts a significant number of couples around the world, despite normal findings in routine infertility tests. This review examines the role of DNA damage, especially in spermatozoa, as a potential cause of unexplained infertility. Sperm DNA fragmentation (SDF), often not detected in conventional sperm analysis, has emerged as a key biomarker for assessing male fertility potential. Elevated DNA fragmentation index (DNA) levels, caused primarily by oxidative stress, environmental toxins and incorrect chromatin remodelling, have been associated with poor reproductive performance, including miscarriage and Assisted Reproductive Technologies (ART). In addition, subclinical factors in women, such as early-stage endometriosis or luteal phase defects, may contribute to the diagnosis of uterine fibrosis. Advanced diagnostic techniques such as Terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL), Sperm Chromatin Structure Assay (SCSA) and Comet Assay offer more accurate detection of DNA damage. An understanding of these molecular factors is essential for specific treatment strategies and to improve the success rate of both natural and artificial insemination.

Keywords: unexplained infertility, DNA damage, sperm DNA fragmentation, oxidative stress, DNA fragmentation Index, assisted reproductive technologies

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