Aneuploidy refers to the decrease or increase of chromosome number. Because there are thousands of genes on chromosomes, the partial deletion or increase of chromosomes seriously affects the transmission of genetic material, leading to miscarriage or premature death of newborns. Surviving newborns usually have birth defects, slow growth or abnormal functions, including mild to severe mental disability, infertility or short life expectancy.

The most common sex chromosome aneuploidy is Klinefelter syndrome, and the prevalence rate is 1/500. The main features of this disease are specific function, learning disabilities, congenital heart defects, intestinal atresia, epilepsy, childhood leukemia and early Alzheimer's Harmo's disease. About 43% of pregnant women miscarry or stillbirth, while the median survival time of such patients in developed countries is as high as 60 years old.

Extended data

Who needs aneuploidy screening?

Regardless of the age of pregnant women, doctors should tell them to participate in aneuploidy screening. The specific screening method depends on the willingness of pregnant women and their families to know fetal information, past medical history and the number of fetuses. Other factors include maternal age, accurate measurement of nt value, sensitivity and price of screening, and long-term monitoring of children.

The risk factors of aneuploidy are the mother's old age, parents' chromosome 2 1 translocation, previous triplets, abnormal ultrasound results and positive screening test. Pregnant women who have previously given birth to malformed fetuses or fetuses with chromosomal abnormalities have an increased risk of recurrence. Although old age is a risk factor, all pregnant women should be screened for aneuploidy in early pregnancy.

Refer to Baidu Encyclopedia-Noninvasive DNA Prenatal Detection Technology