Objective: To evaluate the effect of vaginal isosorbide mononitrate (IMN) plus oral hydration compared
with oral hydration alone in improving the amniotic fluid index (AFI) and obstetric and perinatal outcomes
in pregnancies complicated by isolated oligohydramnios (IO).
Design: A randomized controlled trial.
Setting: Obstetrics and Gynecology Department, Benha University Hospital.
Materials and methods: The study included 210 singleton pregnancies (>28 gestational weeks) complicated
by IO. Participants were scheduled into two equal groups. The study group received vaginal isosorbide
mononitrate plus oral hydration and the control group received oral hydration plusplacebo vaginal
tablet. The amniotic fluid index was assessed at randomization, 24 h after treatment then weekly till
delivery.
Results: One-hundred participants completed the study in each group. A significant increase of AFI was
detected 24 h after treatment in both groups. This effect did not continue for more than one week unless
IMN was added. The mean AFI was significantly higher in IMN group at the final assessment. The IMN
group had significantly higher gestational age on the time of delivery, prolonged randomization delivery
interval, a lower cesarean delivery rate, and their neonates were less likely to have low birth weight, low
Apgar score, and admission to the neonatal intensive care unit. Neonatal deaths were reported in one case
of the study group and 5 in the control group, and the difference was not significant.
Conclusion: Nitric oxide donors may offer a promising choice in improving amniotic fluid volume and
pregnancy outcomes in cases of isolated oligohydramnios. |
