Influence of a single course of antenatal betamethasone on the maternal-fetal insulin-IGF-GH axis in singleton pregnancies.
OBJECTIVE
We examined the hypothesis that a single course of antenatal betamethasone influences the maternal-fetal insulin-IGF-GH axis.


METHODS
A prospective, observational, pilot study consisting of four groups of pregnant women: (I) received betamethasone and delivered <2 weeks post treatment; (II) received betamethasone and delivered >2 weeks post treatment; (III) untreated women who delivered <37 weeks (preterm controls); (IV) untreated women who delivered >37 weeks (term controls). Maternal and mixed umbilical cord blood was collected at delivery and analyzed for insulin, glucose, IGF-I, IGF-II, IGFBP-1, IGFBP-3, GH, and GHBP.


RESULTS
Betamethasone increased maternal insulin, glucose and IGF-I levels without affecting IGFBPs. In the fetal compartment, betamethasone treatment was associated with a delayed suppressive effect on GH and a sustained suppressive effect on IGF-II levels. There were no differences in infant size or neonatal morbidities between patients who delivered <2 weeks or >2 weeks post betamethasone treatment. In Group IV, birth weight correlated positively with cord IGF-I levels (r2=0.41, p=0.0098) and negatively with cord IGFBP-1 levels (r2=0.51, p=0.0039), and ponderal index correlated negatively with cord IGFBP-1 levels (r2=0.27, p<0.05).


CONCLUSIONS
A single course of antenatal betamethasone influences the maternal-fetal insulin-IGF-GH axis, particularly fetal IGF-II levels, without measurable anthropometric changes at birth. Whether these effects have implications beyond the neonatal period remains to be determined.
Ahmad
Irfan
I
Division of Neonatal-Perinatal Medicine, Department of Pediatrics, University of California Irvine, Orange, CA 92868, USA.
Beharry
Kay D A
KD
Valencia
Arwin M
AM
Cho
Steve
S
Guajardo
Leonel
L
Nageotte
Michael P
MP
Modanlou
Houchang D
HD
D001623:Betamethasone / Q000494:pharmacology* / Q000627:therapeutic use; D001724:Birth Weight / Q000187:drug effects; D001786:Blood Glucose / Q000032:analysis / Q000187:drug effects; D005260:Female; D005312:Fetal Blood / Q000187:drug effects; D005865:Gestational Age; D013006:Growth Hormone / Q000097:blood*; D006801:Humans; D007328:Insulin / Q000097:blood*; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000097:blood; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D007335:Insulin-Like Growth Factor II / Q000032:analysis; D008431:Maternal-Fetal Exchange / Q000187:drug effects*; D010865:Pilot Projects; D010920:Placenta / Q000098:blood supply / Q000187:drug effects; D011247:Pregnancy; D011256:Pregnancy Outcome; D047928:Premature Birth / Q000188:drug therapy / Q000517:prevention & control; D011295:Prenatal Care / Q000379:methods; D013997:Time Factors
D001786:Blood Glucose; D007328:Insulin; D018970:Insulin-Like Growth Factor Binding Protein 1; D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II; D013006:Growth Hormone; D001623:Betamethasone