Fetal and placental growth rate in @entity742 has been manipulated by removal of endometrial caruncles prior to conception. This produced two groups of fetuses, one in which prenatal growth rate was similar to normal and a second group in which the fetuses were about half of the normal size. The mortality in the latter group was high, particularly after catheterisation, and there was evidence of early @entity204 and fetal reabsorption. Prior to 125 days the relationship between fetal and placental size was poor, but after 126 days a close correlation between the two was apparent. The small fetuses had comparably small placentas and in all cases there was a close relationship between fetal and placental weight. The experimental @entity851 was associated with hypoglycaemia, @entity519 and hypoinsulinaemia. Plasma T3, T4 and particularly prolactin were very low in the small fetuses whilst levels of @entity701 and @entity493 were high. In contrast to the controls these fetuses showed little evidence of net @entity413 , @entity493 or @entity880 consumption. Infusion of 50% @entity413 into the pregnant ewe, sufficient to elevate maternal plasma @entity413 concentrations 2 to 3 fold, caused a comparable increase in the plasma concentrations of normal fetuses but only a 50% rise in the concentration in small fetuses. In contrast administration of 50% O2 to the ewes sufficient to cause a 2 to 3-fold increase in maternal @entity4095 caused only a small increase of arterial @entity4095 of normal fetuses but doubled that to normal levels in small fetuses. The results are discussed in relation to the effect of reduced placental size causing a fall in placental and transport and transport capacity and significance of this to the associated @entity1592 .

Studies on experimental XXXX in @entity742 . The effects of a small placenta in restricting transport to and growth of the fetus.

@entity851 :: ('MESH:D006130', 'Disease') :: ['growth retardation'] @entity4095 :: ('MESH:C093415', 'Chemical') :: ['PO2'] @entity742 :: ('9940', 'Species') :: ['sheep'] @entity1592 :: ('MESH:D005317', 'Disease') :: ['fetal growth retardation'] @entity519 :: ('MESH:D000860', 'Disease') :: ['hypoxia'] @entity701 :: ('MESH:D006854', 'Chemical') :: ['cortisol'] @entity880 :: ('MESH:D019344', 'Chemical') :: ['lactate'] @entity204 :: ('MESH:D003643', 'Disease') :: ['intra-uterine death'] @entity493 :: ('CHEBI:16449', 'Chemical') :: ['alanine'] @entity413 :: ('MESH:D005947', 'Chemical') :: ['glucose']
@entity851 :: (MESH:D006130,Disease) :: ['growth retardation']
