The gel typically takes about 6 hours to work. Some hospitals put the gels in at night, then re-assess you in the morning. Using the prostaglandin gel makes your labour much more natural if the cervix is thick. It certainly reduces the number of caesarean sections, which used to be associated with inductions of labour in women with an unfavourable cervix. Sometimes, it is necessary to use more than one gel treatment before ARM is possible.
Many women start contracting and go into labour a few hours after having the gel.
Well, that is the big question, and I don't know that there's any good evidence from studies to suggest one way or another. This means that contractions are started with an unfavourable cervix, often with the membranes still intact. So, not only is it unnatural for the contractions to start with the cervix still thick, the contractions are less effective. I don't think the contractions are necessarily more painful per se , just that they started more quickly. It is usual to start the drip slowly and increase it gradually as your contractions start.