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Aneuploidy in Conception
• Monosomies have one missing chromosome from a pair.
• All are lethal, resulting in failed implantation or early loss, with the exception of Turner Syndrome (45, XO).
• Trisomies have an extra chromosome.
• Some have higher implantation
potential while others are unlikely to implant.
• Trisomies for chromosomes 15, 16, and 22 can implant and will miscarry in the first trimester.
• Trisomies for chromosomes 13, 18, 21, X and Y can implant and even result in live birth.
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Aneuploidy in Conception
IVF embryos
(n = 1069)
Trisomy 54.3% (580/1069) Monosomy 45.7% (489/1069) Polyploidy 0% (0/1069)
1st trimester spontaneous abortions (n = 447)
Trisomy 83% (362/447)
Monosomy 6.3% (28/447) Polyploidy 10.7% (48/447)
Although monosomies are routinely documented in IVF embryos, they are rarely observed post‐implantation (Rodriguez‐Purata et. al. Fertil Steril 2015).
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