Association of heteromorphism of chromosome 9 and recurrent abortion (ultrasound diagnosed blighted ovum): A case report.

BACKGROUND: Chromosomal disorders are the most common cause of first trimester spontaneous abortion. Among the human chromosomes, chromosome no.9 was the most common structural chromosomal variant and it is not thought to be of any functional importance, which often considers as a normal variation in structural polymorphisms, nevertheless there are some studies which claim that there is an association between heteromorphism of chromosome no.9 and some pregnancy complication.

CASE: To postulate any correlation between chromosome no. 9 heteromorphism and recurrent abortion, chromosomal analysis was performed on the basis of G-banding technique at high resolution for a couple with the history of 4 ultrasound diagnosed blighted ovum and Chromosome constitution appeared with chromosome no.9 heteromorphism in all 30 metaphases screened for both partners (9p11-q13).

CONCLUSION: Observation of reproductive failure in couples with heteromorohic pattern of chromosome no.9 suggests that, although the heteromorphism of chromosome no.9 is not a rare condition which often consider as a normal variation with no evidence of any phenotypic effect of patient, nevertheless it seems as if the location of heteromorphic region maybe interfere with meiotic events like the phenomenon of crossing over or miotic segregation of fertilized egg that eventually lead to the development of fertilized eggs with chromosomal abnormalities leading to the possibility of anemberyonic pregnancy, therefore chromosomal analysis for detecting of chromosome no.9 heteromorphism for couples with the history of ultrasound diagnosed blighted ovum will be strongly suggested.