Table 1.

Mean ± SD of cardiac diameter, biparietal diameter (BPD) and C/B ratio for each gestational week, according to affected and unaffected fetuses

Gestational weeks	Number of cases (n)	Cardiac diameter (mm) (Mean ± SD)		P value	BPD (mm) (Mean ± SD)		P value	C/B ratio (Mean ± SD)		P value
		Unaffected group	Affected group		Unaffected group	Affected group		Unaffected group	Affected group
18	35	15.39 ± 1.27	17.67 ± 3.31	0.006	39.89 ± 1.06	38.68 ± 4.27	0.212	43.80 ± 4.84	53.46 ± 8.64	< 0.001
19	43	16.57 ± 1.59	19.04 ± 1.29	< 0.001	43.02 ± 1.30	43.38 ± 0.94	0.408	42.44 ± 3.93	51.64 ± 3.93	< 0.001
20	27	17.25 ± 1.26	20.25 ± 1.28	< 0.001	46.99 ± 0.77	46.48 ± 0.95	0.248	41.98 ± 2.86	49.35 ± 3.76	< 0.001
21	15	18.49 ± 0.96	21.11 ± 1.17	< 0.001	50.52 ± 3.54	48.77 ± 3.50	0.353	42.72 ± 6.48	53.89 ± 7.80	< 0.001