The first reported case of double trisomy 10 and 20 in a product of conception.

Background: Double trisomies are rare findings among products of conception and are often lethal to the developing embryo or fetus.

Methods: Here we describe a double trisomy case with symptoms of threatened miscarriage at 9 weeks gestation. Ultrasound revealed an anembryonic pregnancy. Pregnancy was terminated by dilation and curettage at gestational age 11 weeks and 6 days. Histologic examination and chromosome microarray were performed on a formalin-fixed product of conception (POC) sample to identify the cause of the anembryonic pregnancy.

Results: Chromosome microarray analysis revealed a female chromosome complement with double trisomies 10 and 20, arr(10,20)x3, consistent with a karyotype of 48,XX,+10,+20.

Conclusion: To the best of our knowledge, this is the first reported case of double trisomy 10 and 20 in a POC. Due to nonspecific histopathological findings, chromosomal microarray is a powerful tool in identifying and differentiating chromosomal aneuploidies.