Prostaglandins side-effects

Many women complain of an aching pain that is persistent in the lower back and abdomen, following prostaglandin administration. Sometimes this is bad enough to require medication.

Hyper-stimulation of the uterus is another potential side effect. This may cause fetal distress. Using drugs called tocolytics, which allow the uterus to relax, can effectively counteract hyper-stimulation. They are given intravenously but the inhalational route has also been used with success.

Nausea, vomiting, headache, flushing and dizziness are uncommon; even rare and, in most cases, tend to be mild.

Where prostaglandin use is contraindicated

There are a few situations where prostaglandins will not be used, including:

v Where there has been significant antepartum haemorrhage (vaginal bleeding during pregnancy) or where there is confirmed placenta praevia, with or without bleeding, prostaglandins are not used

v In the ocular (eye) condition known as glaucoma.

v When there is an infection in the birth canal.

v When the fetus is lying in an abnormal position such as breech, transversely or oblique.

Prostaglandins can still be used safely where membranes have already ruptured. That is; if the cervix is found to be still in an unfavorable state.

Using prostaglandins in a case of previous cesarean section

A previous cesarean section in itself is not a contraindication. However, many obstetricians are not comfortable with the idea of using prostaglandins in such circumstances. There is also fairly credible evidence that prostaglandins might have a direct weakening effect on the old scar on the womb.

Of course, if the indication for the previous cesarean section is still there, the need for inducing labor will not arise as delivery will be by a repeat cesarean section.

If prostaglandins are used to induce labor in such a situation, close observation will be maintained.

Where prostaglandin use is not necessary

If, on assessing the cervix, it is found to be favorable; prostaglandin use will be unnecessary. The doctor will proceed to rupture the membranes and probably use the oxytocin infusion to stimulate contractions.

If the membranes are already ruptured, then all that remains is to initiate contractions. The oxytocin infusion is used for this.

Potential oxytocin side-effects

Oxytocin is actually a natural chemical which is produced by the pituitary gland in the brain for the same purpose which is to stimulate the womb to contract.

If the oxytocin drip becomes excessive, the uterus may be over-stimulated.

Over-stimulation of the uterus in a woman who has had a number of children in the past could cause rupture of the uterus.

There is also the risk of fetal distress as a result of over-stimulation. This effect can be readily reversed by stopping the infusion or, if deemed necessary, by stopping the drip and administering a tocolytic drug. Such complications are uncommon.

Continues next page