Patient's question:
Urgent question: Is it still useful to do the Down syndrome screening at 20 weeks + 5 days of pregnancy? My husband's older brother has a child with Down syndrome, which makes me very sad. My husband also carries the genetic gene. Due to my own ignorance earlier, I didn't get the Down syndrome screening done in time. Is it too late to do it now? If not, can other detailed tests be done instead?Doctor's answer:
Tandem screening is divided into early and mid-pregnancy screening. Early screening is performed between weeks 11 and 13+6, specifically an NT scan to measure the thickness of the nuchal translucency. Mid-pregnancy screening is conducted between weeks 15 and 20+6, and the results are relatively accurate. If there is a clear family history, it is recommended to directly undergo amniocentesis or non-invasive DNA testing, as these methods provide more accurate results. Amniocentesis and non-invasive DNA testing are advised over prenatal screening, as the accuracy of prenatal screening is still relatively low.