The effects of oral carbohydrate administration on fetal acid base balance.

AIMS

Little evidence-based data are available on the effects of eating and drinking during labor. Intravenous glucose administration has been related to fetal metabolic acidosis. The question is, whether oral intake of carbohydrates effects the fetal acid-base balance.

METHODS

In a double blind, prospective placebo controlled study 100 nulliparous women were randomized at 8-10 cm of cervical dilatation. All women were asked to drink 200 cc of either a carbohydrate solution (containing 25 grams carbohydrates) or placebo. In all women, both arterial and venous umbilical cord pH, pCO2, pO2, HCO3- and base excess/deficit were assessed. In a subgroup of women, whose deliveries were complicated by mild signs of fetal distress, clinical outcome and acid-base status was described separately.

RESULTS

Fetal arterial umbilical cord pH were identical: 7.20 +/- 0.07 in the placebo group and 7.20 +/- 0.08 in the carbohydrate group and the base excess -6.6 +/- 2.8 versus 6.6 +/- 3.7. In the women with mild signs of fetal distress, no differences were observed as well.

CONCLUSIONS

Oral carbohydrate intake during labor seems to be safe regarding the fetal acid-base balance. Further study on the maternal and fetal metabolic parameters is essential to give a more complete picture.