Table 1.

Strengths and Weaknesses of Prenatal Diagnosis Methods

Methods	Strengths	Weaknesses	References
Invasive	Wide range of clinical applications	Invasive and risky	[5, 6]
Amniocentesis	Gold standard;	Invasive means;	[5]
	For detection of fetal chromosomal abnormalities	Risk of abortion for pregnant women
Chorionic villi	For karyotyping and genetic diagnosis;	Invasive, with risk of preterm delivery, intracavitary infection	[6]
Sampling	Detectable at 6–9 weeks	and miscarriage;
		Contaminated samples seriously affect the test accuracy
Non-invasive	Quick, non-invasive, and convenient	Less clinical application at present	[4, 7]
Serum Testing	Non-invasive, detectable in early pregnancy;	Low sensitivity and specificity;	[8]
	For Down syndrome and neurotuberculosis screening	Only as an aid, need to have invasive methods to confirm
Ultrasound	Non-invasive, Detect thickness of the nuchal translucency	A complementary tool, more limited in detecting fetal abnormalities	[9]
	to rule out chromosomal abnormalities
CffDNA	Non-invasive and can be detected as early as 4 weeks;	The minimal, mosaic phenomenon, challenge to detect;	[14–17]
	Contains fetal genetic information for fetal aneuploidy screening	Requires invasive means for confirmation
FNRBCs	Contain the whole genetic information of the fetus;	Low quantity	[23, 25–27]
	Have specific biomarkers (CD71、CD147、GPA);
	A short life cycle, and not affected by the last prenatal examination;
	Can be detected at 6 weeks of gestation