From the Cochrane Reviews comes this review of research that finds AROM (artificial rupture of membranes) does not hasten labor or ensure baby's well-being.
The researchers reviewed 14 randomized controlled trials involving almost 5,000 women and found little evidence for any benefits. Amniotomy did not shorten the length of labor, decrease the need for the labor-stimulating drug oxytocin, decrease pain, reduce the number of instrument-aided births or lead to serious maternal injury or death.
Anecdotally, there have been situations where I know rupture of membranes - both spontaneous (on their own) or artificial - has made a birth happen more quickly. I think it's safe to say we all know of times where late AROM has picked up a slow labor at the end of dilation. Whether or not it's supporting the natural process of labor (it's not), there are times where I've seen it work.
However, we also know that this information is not a surprise to many providers. I think the biggest disadvantage is when it's used to induce prior to 4-5cm (having seen AROM at 1-2cm for induction it seems to shows the least amount of effectiveness) or when labor is moving forward, but not to the appreciation of provider and/or mother. This review only pulled instances where labor had begun spontaneously and AROM was not used for induction.
In my opinion,this is where looking at evidence-based research is key: as providers, we carry alot of anecdotal experience. The important thing for me is that we don't allow those experiences become the truth for us. Giving full informed choice (including research like this) is important for each woman - including that our own experience includes an amount of women that a study this size would consider insignificant.