In one specific group, a significant association between sperm morphology and sperm chromosome content has been found: in teratozoospermic men with a high percentage of macrocephalic, multinucleated and multiflagellate sperm, very high frequencies of aneuploid and polyploid sperm have been reported. Viville et al. [
22] observed a very high frequency of aneuploidy (67%) in a patient with 64% macrocephalic spermatozoa. Benzacken et al. [
38] reported an OAT patient who had 100% macrocephalic sperm heads, 38% with an irregular acrosomal cap and 72% with 2–5 flagella. FISH analysis of 1,148 spermatozoa showed 100% chromosomally abnormal sperm: 21.6% were diploid, 62.4% triploid, 13.3% quadriploid and 2.7% hyperploid. In an OAT patient who had 100% sperm with macrocephalic heads, one to three tails and an absence of an acrosomal cap, In't Veld et al. [
39] reported that normal haploid sperm were virtually absent (<2%), and abnormalities included 40% diploid and 24% triploid sperm. Another report [
40] detailed high frequencies (>50%) of chromosome 18, X and Y disomies in sperm from 3 men with 100% teratozoospermia: double-headed sperm (>20% incidence in all three patients), large-headed multinucleated sperm (>50%) and multiple tail deformities (>50%). Devillard et al. [
41] reported more than 50% sperm aneuploidy for chromosomes 1 and 18 in three patients with 100% large-headed multiflagellate sperm. Bernardini et al. [
42] reported 20% disomy and 10% diploidy in 6 infertile men with macrocephalic or two-tailed spermatozoa. Thus there is consistent evidence for a relationship between these specific morphological sperm abnormalities and abnormal chromosomal constitutions.