Embryonic abnormalities account for approximately 80% of first-trimester abortions.
Chromosomal abnormalities are the most common cause of spontaneous abortion. Autosomal trisomies account for more than half of the abnormal karyotypes (due to nondisjunction or translocation), and monosomy is the next most common anomaly.
More than 90% of cytogenic and morphologic errors are eliminated through spontaneous miscarriages.
Chromosomal abnormalities are found in more than 75% of fetuses aborted in the first trimester.
The rate of chromosomal abnormalities increases with maternal age. In women younger than 30 years, the rate of miscarriage is approximately 12%; thereafter, the rate increases rapidly, exceeding 50% in women older than 45 years
Chromosomal abnormalities are the most common cause of spontaneous abortion. Autosomal trisomies account for more than half of the abnormal karyotypes (due to nondisjunction or translocation), and monosomy is the next most common anomaly.
More than 90% of cytogenic and morphologic errors are eliminated through spontaneous miscarriages.
Chromosomal abnormalities are found in more than 75% of fetuses aborted in the first trimester.
The rate of chromosomal abnormalities increases with maternal age. In women younger than 30 years, the rate of miscarriage is approximately 12%; thereafter, the rate increases rapidly, exceeding 50% in women older than 45 years