I am studying for my shelf exam (my end of rotation exam, for those of you not well versed in the jargon) on ob/gyn. I am using one of a popular series of board review books. Every single question in the chapter on intrapartum fetal monitoring had the use of an intrauterine pressure catheter (IUPC), and most mentioned a fetal scalp electrode.
I am not sure what the prevalence is of IUPC use. I have not seen it in most of the labors I have been to, but I have definitely seen them used. In one labor I went to, the IUPC and/or fetal scalp electrode had to be replaced three times because of problems.
As far as I know, there is no evidence supporting their use. I found this article, which is a rare randomized trial with a significant number of subjects. There seems to be no advantage to using them. When that is the case, I think it is only ethical to use the less invasive intervention, which would be external monitoring.
There are a few quotes I find interesting in this article. Here’s one:
“The American College of Obstetricians and Gynecologists (ACOG) and the Society of Obstetricians and Gynaecologists of Canada (SOGC) advise the use of internal tocodynamometry in selected circumstances, such as when the mother is obese, when one-on-one nursing care is not available, or when the response to oxytocin is limited. The Dutch Society of Obstetrics and Gynaecology recommends its use in all cases of induction or augmentation of labor.2”
Well, I have never seen one to one nursing in labor and delivery in a hospital. Never.
Also, here’s another one:
“Induction or augmentation is necessary in approximately 20% of all deliveries, and internal monitoring is thought to quantify the frequency, duration, and magnitude of uterine activity more accurately than does external tocography.1-3″ (Emphasis mine)
Wow, really? Unfortunately, there are poor statistics on the prevalence of interventions in labor, but Listening to Mothers cites an induction rate of 48% for first time moms, and “Only 41% of the women had a labor that began on its own.” This link didn’t have the statistic for augmentation, but from what I remember, more than 70% of labors were augmented by oxytocin.
So, 20% of that is necessary, and what does that make the rest? Depends on who you ask. Some practitioners will say it is active management, aka “doing what we can to get the baby out…that’s what you’re here for.” I call it excessive interventions that lead to possible iatrogenic risk.