Mulhair L Prospective cohort study - AmnioSense Int J Obstet & Gynecol 2008
A UK study looked at 157 women attending the antenatal unit at St Thomas’ Hospital in London with a suspected leak of amniotic fluid. Some had been referred to the unit by their GP or midwife, while others were so concerned they had gone straight to the hospital. In all, 139 between 18 and 24 weeks’ gestation, were eligible for the trial.
These women were asked to wear the AmnioSense panty-liner for 20 minutes, or until they were aware of any dampness. Ten minutes after they removed the panty-liner, when any colour change had stabilised, it was checked by a midwife, who recorded the results. A second midwife, who was given no information about the findings, then carried out a speculum examination to try to detect any pooling of amniotic fluid.
Comparisons confirmed that AmnioSense detected 98% of leaks caused by urine and harmless vaginal discharges and 67% of cases where there was a leak of amniotic fluid.
Crucially, two out of five cases of rupture (38%) could have been diagnosed without the need for an invasive speculum examination; a quarter of the ‘false’ positives were subsequently linked to the presence of bacteria or fungal infections; rupture was retrospectively identified in two women and seven went on to deliver within 3 days — suggesting AmnioSense has greater sensitivity and accuracy than speculum examination.
The study, published in the International Journal of Obstetrics and Gynaecology concluded: “If used in clinical practice, the reduction in the number of speculum examinations will substantially benefit women and service providers.”