The association between maternal diabetes and polyhydramnios is common. Polyhydramnios
is often the first sign the maternal glucose intolerance may be present (even
prior to changes in maternal glucose levels).
The mechanism for the polyhydramnios in these patients is not known:
- An increase in fetal urine
production secondary to the diuretic effect of relative hyperglycemia has
been suggested as a possible mechanism (1). although this is still
controversial (2).
- Solute loading in ovine
fetuses are known to cause polyhydramnios (3).
Correcting the maternal glucose levels can arrest the
progression of the polyhydramnios, but the amniotic fluid does not usually
return to normal.
- Kurjak A, Kirkinen P, Latin V
et.al. Ultrasound assessment of kidney function in normal and
uncomplicated pregnancies. Am J Obstet Gynecol 1981;141:266.
- Van Otterlo LCM, Wladimiroff
JW, Wallenberg HCS. Relationship between fetal urine production and
amniotic fluid in normal pregnancy, and pregnancy complicated by diabetes.
Br J Obstet Gynecol 1977;84:205.
- Powell TL, Brace RA. Elevated
plasma lactate produces polyhydramnios in the sheep. Am J Obstet Gynecol
1991;165:1595.