Contents of chemical elements in stomach during prenatal development: different age-dependent dynamical changes and their significance

Table 4 Stomach weights of fetus aging from 4 to 10 months

Month-age	4	5	6	7	8	9	10
Weight (gram)	0.35	0.94	1.73	3.17	4.20	5.41	8.93
	0.12 (6)	0.45 (19)	0.64 (14)	0.74 (9)	1.19 (7)	0.76 (6)	2.10 (5)
Fixed ratio (%)	100	268.6	494.3	905.7	1200.0	1545.7	2551.4
Circular ratio (%)	-	268.6	184.0	183.2	132.5	128.8	165.1

The data in the upper row was average mean, that in the lower row was standard deviation, with the case number in bracket.

Fixed ratio = stomach weight of fetus age of i month/stomach weight of fetus age of i month× 100%;

Circular ratio = stomach weight of fetus age of j month/stomach weight of fetus age of i month× 100%;

(i = 4, 5...10; j = i + 1, j_max = 10)