The relation of insulin, leptin and IGF-1 to birthweight in offspring of women with type 1 diabetes.
OBJECTIVE
Maternal diabetes is associated with excess foetal growth. We have assessed the influence of maternal diabetes on hormones associated with foetal growth and the relationship of these hormones to birthweight.


METHODS
Case-control study.


METHODS
Singleton offspring of mothers with type 1 diabetes (ODM, n = 140) and control mothers (Control, n = 49).


METHODS
Birthweight, cord blood insulin, proinsulin, 32-33 split proinsulin, leptin, IGF-1, IGFBP-3, cortisol.


RESULTS
Maternal diabetes was associated with higher birthweight (ODM 3.80 +/- 0.69 kg; Control; 3.56 +/- 0.52 kg, P = 0.02) and marked increases in insulin (median [interquartile range]: ODM 110 [60-217] pmol/l; Control 22 [15-37] pmol/l; P < 0.0001) and leptin (ODM 32 [15-60] ng/ml; Control 9 [4-17] ng/ml; P < 0.0001) but no absolute difference in IGF-1 (ODM 7.9 [6.2-9.8] nmol/l, Control 7.5 [6.2-9.8] nmol/l, P = 0.24) or its principle binding protein IGFBP-3 (ODM 1.63 +/- 0.38 micro g/ml, Control 1.63 +/- 0.28 micro g/ml; P = 0.12). Individually, insulin, insulin propeptides, leptin, IGF-1 and IGFBP-3 were significantly (P < 0.05) correlated with birthweight (in ODM and Control). IGF-1 and leptin were positively related to birthweight independently of each other and insulin in both ODM and Control. By contrast, insulin showed independent relationships to birthweight in ODM (P < 0.0001) but not in Control (P = 0.4).


CONCLUSIONS
Maternal diabetes is associated with marked elevation of insulin and leptin in cord blood of their offspring. Hormonal correlates of birthweight differ between ODM and Control with an independent relationship of insulin to birthweight observed only in ODM.
Lindsay
R S
RS
University of Glasgow, Division of Cardiovascular and Medical Sciences, Gardiner Institute, Western Infirmary, Glasgow, UK. r.lindsay@clinmed.gla.ac.uk
Hamilton
B A
BA
Calder
A A
AA
Johnstone
F D
FD
Walker
J D
JD
D000328:Adult; D001724:Birth Weight; D016022:Case-Control Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood; D005260:Female; D005312:Fetal Blood / Q000737:chemistry*; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007231:Infant, Newborn; D007328:Insulin / Q000097:blood*; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D020738:Leptin / Q000097:blood*; D011247:Pregnancy; D011254:Pregnancy in Diabetics / Q000097:blood
D006442:Glycated Hemoglobin; D006854:Hydrocortisone; D007328:Insulin; D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I; D020738:Leptin