Mode of Induction in Fetal Growth Restriction and Its Affects on Fetal and Maternal Outcomes

Intra uterine growth restriction (FGR) is a condition in which the fetus does not realize its growth potential in uterus. The excepted definitions of this condition are fetal weight estimation below the 10th percentile per gestational week. Severe growth restriction is defined as estimated weight below the 3rd percentile. It is well known that fetuses which are growth restricted are subjected to a higher degree of complications during pregnancy and delivery such as fetal distress, hypoxic damage, intra uterine fetal demise and complications in the neonatal period including prolonged NICU hospitalization, cerebral palsy, hypoxic ischemic encephalopathy and also long term affects such as neuro developmental complications.

Common practice in managing these cases is induction of labor at term around 37 weeks of gestations to prevent these complications as it established that during this time there is a substantial rise in pregnancy complications including fetal demise.

There are no clear guide lines how to induce labor in such cases and it is not known what is the safest and the most effective way to induce labor in these cases. Prior studies have found the rate of successful vaginal birth in these cases vary between 50 and 80%. There are a number of methods of labor induction and delivery available including the use of vaginal prostaglandins (PGE2) for cervical ripening, intracervical balloon catheter or planned cesarean. In most cases when aiming for vaginal delivery the choice is between ripening of the cervix with balloon catheter in combination with Pitocin or ripening with prostaglandins. It is not known which method is safer and more successful in growth restricted fetuses.