Effect of oral and intravenous hydration on oligohydramnios

To investigate whether oral or intravenous hydration affects oligohydramnios in cases with normal biophysical profile scores.

One hundred twenty-four gravidas with singleton pregnancies at or near term were identified during a 16-month period retrospectively as having oligohydramnios. A total of 50 subjects with normal biophysical profiles (8 of 10) whose labor was not induced at once fell into two nonrandom, convenience sample groups: (1) 20 who were advised to drink fluids, and (2) 30 given intravenous hydration. The remaining 74 cases with oligohydramnios consisted of 60 gravidas with normal biophysical profile scores and another 14 with low scores (< or = 6 of 10), all of whom had labor induced promptly.

Cases with normal fetal status showed comparably favorable amniotic fluid index changes. In all, 62.5% and 44.0% demonstrated improved indices after oral and intravenous hydration, respectively; mean change in amniotic fluid index was +0.7 and +0.6. The amount of intravenous hydration did not correlate with the frequency of amniotic fluid index change (46.6% increase with intravenous volumes of < or = 2,000 mL, 40.0% with volumes > or = 2,500 mL), or with magnitude of change (average +1.3 and +0.6).

Oral and intravenous hydration may correct uncomplicated oligohydramnios, but neither appears to be particularly advantageous over the other.