If the prostaglandins do not stimulate the woman's labour, an oxytocin drip would be needed in the delivery suite.
Advantages. The use of prostaglandins are often associated with a more positive experience for the woman. This is because it feels more 'natural', and once the initial monitoring is completed the woman is free to move around, using the shower or bath, without being attached to a drip or a fetal monitor, until the baby is born. After the labour has started she may be able to return to a birth centre (or home) if she originally planned to birth there.
Using prostaglandins (as an alternative to an oxytocin drip) has also been associated with less chance of needing an epidural, therefore less chance of requiring a Caesarean, forceps or ventouse delivery. Using prostaglandins, as opposed to expectant management (or just waiting), decreases the chances of infection for the mother and / or baby.
Disadvantages. Prostaglandins have an increased chance of causing nausea, vomiting and diarrhoea for the woman. It also increases the chances of the woman and / or baby developing an infection, when compared with an oxytocin drip. This is generally attributed to an increase in the number of vaginal examinations.
Prostaglandins have been associated with an increased need for pain relief, when compared with just waiting for labour to start on its own. It can occasionally overstimulate the woman's uterus, stressing her baby due to reduced oxygen. In some cases a Caesarean is needed (using a general anaesthetic, because there is not enough time to administer an epidural). Unlike the oxytocin drip, prostaglandins cannot be turned down or off. Once it is in, it's in! However, Cervidil pessaries are inserted with a string attached, similar to a tampon. If the uterus becomes over stimulated, the medication can be quickly withdrawn to minimise these effects, then ventolin may be given to try and suppress the contractions.