what are the causes of abnormal sperm morphology?
['DNA abnormalities: If the DNA does not condense properly due to missing or added chromosomes, the shape of the head may be abnormal (not all abnormal sperm contain chromosomal defects)', 'Genetic trait.', 'Chemical exposure.', 'Increased testicular temperature.', 'Smoking.', 'Alcohol use.', 'Certain medications.']