Table 7.

Correlation between yolk sac diameter in first trimester scan and pregnancy outcome in the second trimester scan.

Yolk sac (mm)	Pregnancy outcome				Total		Chi-square test
	Positive fetal life		Negative fetal life
	No.	%	No.	%	No.	%	x2	p-value
Yolk sac <2mm	0	0.0%	6	42.9%	6	5.0%	60.094	<0.001**
Yolk sac 2-5mm	86	81.1%	1	7.1%	87	72.5%
Yolk sac >5mm	20	18.9%	7	50.0%	27	22.5%
Total	106	100.0%	14	100.0%	120	100.0%

Using: Chi-square test; p-value<0.001 HS.