Non-invasive Prenatal DNA Testing
Introduction

Non-invasive Prenatal DNA Testing (NIPT) is a non-invasive, convenient, accurate, and rapid technology for detecting rapid screening technology for fetal chromosomal aneuplodies, such as trisomy 21 (Down's syndrome), trisomy 18 (Edward's syndrome) and trisomy 13 (Patau's syndrome).

Applicable
  • NIPT is suitable for singleton or twin pregnant women over 12+0 weeks of gestation. The target diseases include three common fetal chromosomal aneuploidies, i.e. trisomy 21, trisomy 18, and trisomy 13.
  • The risk value of common chromosomal aneuploidy in fetuses is between the high-risk cutoff value and 1/1000 in pregnant women by serological screening;
  • Pregnant women with contraindications to invasive prenatal diagnosis (such as threatened abortion, fever, bleeding tendency, the active phase of chronic infection, Rh-negative blood type of pregnant women, etc.).
  • Pregnant women miss the optimal time of serological screening due to beyond 20+6 weeks, but still require evaluation of the risk of trisomy 21, trisomy 18 and trisomy 13.
Cautionalbe
Pregnant women who have any of the following situations should be treated with caution, including:
  • High-risk of serological prenatal screening in the first and/or second trimester;
  • The expected delivery age is ≥ 35 years old;
  • Severe obesity (BMI>40);
  • Conception through in vitro fertilization - embryo transplantation;
  • A couple have had a fetus with chromosomal abnormalities, but they themselves do not have chromosomal abnormalities;
  • Twin or multiple pregnancy;
  • Other situations that clinicians consider can significantly affect the accuracy of NIPT results.
Inapplicable
  • The gestation week is<12+0;
  • One partner in a couple has chromosomal abnormalities;
  • The pregnant women have received allogeneic blood transfusion, transplantation, or cell therapy within 1 year;
  • Fetal ultrasound examination indicates structural abnormalities that require invasive prenatal diagnosis;
  • One or both partners in a couple have a familial history of genetic disease,or high risk of fetal genetic diseases;
  • Combined with malignant tumor during pregnancy;
  • Other situations that clinicians consider can significantly affect the accuracy of NIPT results.
Except for the inapplicable situations mentioned above, pregnant women and their families can choose NIPT with fully informed consent.