Table 1. Wet weight, fetal to placental wet weight ratios, and placental water content of Igf2 P0^+/–, Igf2 null^+/–, and wild-type^+/+ conceptuses by comparing mutants with corresponding wild-type littermates in the same litters.

Gestational age	Mouse strain	n	Fetal wet weight, g	Placental wet weight, g	Fetal-to-placental weight ratios	Placental water content, % (n)
E14	Igf2 P0+/–	32	0.149 ± 0.003	0.075 ± 0.002	2.04 ± 0.04	ND
	Wild-type+/+	29	0.150 ± 0.004	0.091 ± 0.002	1.68 ± 0.04	ND
	(% of wild-type)		99 NS	82***	121***
	Igf2 null+/–	34	0.118 ± 0.003	0.072 ± 0.002	1.68 ± 0.05	ND
	Wild-type+/+	46	0.151 ± 0.003	0.091 ± 0.002	1.69 ± 0.04	ND
	(% of wild-type)		78***	79***	99 NS
E16	Igf2 P0+/–	111	0.414 ± 0.004	0.075 ± 0.002	5.71 ± 0.07	83.3 ± 1.1 (32)
	Wild-type+/+	127	0.432 ± 0.003	0.105 ± 0.001	4.23 ± 0.07	83.5 ± 0.5 (32)
	(% of wild-type)		96**	71***	135***
	Igf2 null+/–	80	0.286 ± 0.004	0.065 ± 0.001	4.50 ± 0.08	83.2 ± 0.6 (41)
	Wild-type+/+	91	0.435 ± 0.004	0.104 ± 0.001	4.22 ± 0.07	83.7 ± 0.6 (33)
	(% of wild-type)		66***	63***	107**
E19	Igf2 P0+/–	116	0.926 ± 0.009	0.063 ± 0.001	15.25 ± 0.24	82.0 ± 0.5 (22)
	Wild-type+/+	117	1.228 ± 0.009	0.095 ± 0.001	13.46 ± 0.22	82.5 ± 0.4 (17)
	(% of wild-type)		75***	66***	113***
	Igf2 null+/–	116	0.571 ± 0.008	0.051 ± 0.001	11.60 ± 0.16	80.9 ± 1.1 (32)
	Wild-type+/+	108	1.215 ± 0.008	0.089 ± 0.001	13.88 ± 0.16	83.8 ± 0.7 (33)
	(% of wild-type)		47***	57***	84***

ND, not determined; ^**, P < 0.01; ^***, P < 0.001; NS, not significant P > 0.05. Data is mean ± SE.