In which circumstances is the use of prostaglandins not necessary?
If, on assessing the cervix, it is found to be favourable, -then prostaglandin use will be unnecessary. The doctor will proceed to rupture the membranes and probably use the oxytocin drip to stimulate contractions.
If the membranes are already ruptured, then all that remains is to initiate contractions. The oxytocin infusion is used for this.
What are the potential side-effects of oxytocin?
Oxytocin is actually a natural chemical which is produced by the pituitary gland in the brain for the same purpose - to stimulate the womb to contract.
If the oxytocin drip becomes excessive, the uterus may be over-stimulated.
Over-stimulation 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.
How is the oxytocin drip administered and controlled?
Most labour ward units use either an infusion pump or a syringe driver. With these methods, one can very accurately determine the rate at which oxytocin is being administered. The rate can therefore be adjusted upwards or downwards, according to need and response.
How does oxytocin differ from syntocinon?
There is no difference. Oxytocin is a generic name and Syntocinon®, is the commonly used brand name (in the UK and Europe). The other common brand name is Pitocin®. They are the same thing.
What about syntometrine?
This is a combination of Syntocinon (oxytocin) and ergometrine. It has no role to play in induction or augmentation of labour. In fact, its use is contraindicated during pregnancy. It is used after delivery to facilitate expulsion of the afterbirth (placenta) and to produce sustained uterine contractions, which are essential in preventing excessive blood loss.
Are there any other methods of induction, apart from those already discussed?
Some hormones and chemicals, including oestrogen, have been tried and found to be either very slow or ineffective. These are therefore not in use for this purpose.
Mechanical preparation of the cervix, using what are termed as ‘laminaria’ (vaginal pessaries made from a kind of starch, - extracted from seaweed) and some chemically impregnated cervical "sponges" were once tried, especially in the United States. All these methods have not taken hold because of their comparatively inferior effect and the potential risk of infection.