Physiological changes in insulin resistance in human pregnancy: longitudinal study with the hyperinsulinaemic euglycaemic clamp technique.
OBJECTIVE
To perform measurements of insulin resistance serially in pregnancy and after childbirth in normal women.


METHODS
Longitudinal study.


METHODS
Teaching hospital.


METHODS
Ten normal women were studied using the hyperinsulinaemic euglycaemic clamp technique before pregnancy, at 16, 26 and 36 weeks gestation, and 8 weeks after delivery. All women breastfed their infants. Insulin resistance was measured by the glucose infusion rate required to maintain the plasma glucose at 4.5 mmol/l.


RESULTS
There was a progressive increase in insulin resistance in all women as pregnancy progressed. The increase in resistance was most marked between 16 and 26 weeks of gestation, with only minimal progression thereafter. Lactation does not alter insulin resistance.


CONCLUSIONS
The timing and extent of changes in insulin resistance are of physiological importance because they affect all classes of maternal and fetal substrates.
Department of Obstetrics and Gynaecology, University of Sheffield, UK.
K
K
Stanley
R
R
Fraser
C
C
Bruce
D000328:Adult; D005260:Female; D005865:Gestational Age; D005947:Glucose / Q000008:administration & dosage; D015309:Glucose Clamp Technique; D006801:Humans; D006946:Hyperinsulinism / Q000378:metabolism*; D007262:Infusions, Intravenous; D007333:Insulin Resistance / Q000502:physiology*; D008137:Longitudinal Studies; D049590:Postpartum Period / Q000378:metabolism; D011247:Pregnancy; D011248:Pregnancy Complications / Q000378:metabolism*
D005947:Glucose