Obstetrical History: Labor induction, Part 2 When Electricity did not work Stripping membranes was invented!
Separation of Membranes by Forefinger (Hamilton 1810)
Use of digital stripping or pushing the membranes off the interior of the cervix or instrumentation of fetal membranes is a procedure familiar to most obstetricians. It is done by putting one's finger through the cervix, then feeling the layer between the amniotic sac and the wall of the uterus and pushing with the finger so as to cause separation of the membranes from the lower uterine segment as far as possible by the examining finger.
Theoretically, stripping of the membranes should have a powerful effect in stimulating labor because the procedure causes the uterus and cervix to release compounds called prostaglandins and then there is an increase in prostaglandin metabolites in maternal circulation. In addition, the release of prostaglandins is proportional to the area of membranes separated from the uterus. A variety of catheters with or without guiding stylets have been used over the centuries. Some obestricians would use this on a weekly basis to prevent their patients from going overdue. Digital and instrumentation separation of the membranes while effective proved irritating and painful to some women. Consequently, these methods were rarely used (Clinical Obstetrics and Gynecology; Amniotomy to Induce Labor; 1995; pages 256), although in modern times the digital technique has become popular.