Fundal pressure involves using the hands (manual fundal pressure) to push on the upper part of the uterus and down toward the birth canal. It is used during the second stage of labour to shorten the labour and assist in vaginal birth, either as routine practice or because of complications such as fetal distress, failure to progress, maternal exhaustion, or medical conditions where prolonged pushing is contraindicated, for example if the mother has heart disease. Also an inflatable girdle has been used in research settings to provide fundal pressure.
Potential risks with its use include uterine rupture, anal sphincter damage, newborn fractures or brain damage, and increased blood transfusion between the mother and her unborn baby. This may be important with rhesus factor or when the mother has HIV, hepatitis B or other viral disease.
The review authors found no trials on the more widely used manual fundal pressure. There was only one controlled trial studying fundal pressure by inflatable belt. It involved 500 women who had epidural analgesia and were in the second stage of labour. The methodological quality of the trial was good. The number of women experiencing spontaneous vaginal births was similar with or without applying fundal pressure. The trial did not provide sufficient evidence to determine any safety issues of the manoeuvre for the baby, measured as low Apgar scores, low arterial fetal cord pH, or admission to the neonatal unit. Blinding was not possible with this intervention. It may have been perceived that the belt was 'doing the work' so that the women pushed less hard and the midwives encouraged them less enthusiastically. The number of women with an intact perineum increased with use of the belt but also anal sphincter tears increased, all but one associated with an instrumental delivery.