Abstract
Plasma glucose, insulin and glucagon concentrations were measured before and after
the ingestion of a protein-rich meal in 11 healthy pregnant women in the last trimester
of pregnancy, and again in the same subjects postpartum. Compared to postpartum, basal
levels of plasma glucose were lower in late pregnancy whereas basal insulin and glucagon
concentrations were both enhanced. After the meal, insulin and glucagon concentrations
in plasma increased in gestation as well as postpartum. Plasma glucose increased slightly
in pregnancy but remained unchanged postpartum. The mean insulin response to the meal
was unaffected by pregnancy whereas that of glucagon was reduced. Thus following protein
ingestion, plasma glucose rose in pregnancy in spite of unchanged levels of insulin
and depressed levels of glucagon. Favouring anabolism, the reduced glucagon response
to protein ingestion in pregnancy fits in the concept of 'facilitated anabolism' in
late pregnancy and, moreover, it lend further support to the idea that changes in
glucagon secretion per se are not involved in the pathogenesis of the diabetogenicity
of pregnancy.
Key words
Glucagon - Insulin - Blood Glucose - Human Pregnancy
