"We do not recommend that amniotomy, also known as breaking the waters, should be used routinely as part of standard labour management and care" says Cochrane Researcher Rebecca Smyth, after completing a systematic review of relevant research studies. "Women should be informed that it doesn't shorten the first or second stage of labour, it doesn't affect the woman's satisfaction with her childbirth experience, and doesn't result in the child being in better condition immediately after birth."
This Cochrane Systematic Review found that breaking the waters may be associated with a slightly (non-significantly) higher rate of Caesarean section. Breaking the waters may cause changes in the baby's heart rate.
The aim of breaking the waters is to speed up and strengthen contractions, with the intention of shortening labour. The membranes are punctured using a long handled hook, and it is thought that hormones in the amniotic fluid that flows out will stimulate contractions. In some centres, it is performed as a routine part of care for all women in labour - in others it is used only for women with a clinical need to have their waters broken.
Ms Smyth came to these conclusions after she and colleagues had identified 14 relevant studies that involved almost 5,000 women. The overall quality of the studies was variable, making it difficult for the group to give firm recommendations about the use of amniotomy. There is a need for further research in this area.
"Our evidence suggesting this lack of effect should be discussed with women in the antenatal period," says Smyth.