Counterpoint: Cervical Length Screening is Not Ready for Prime Time

February 22, 2012

At the Society of Maternal and Fetal Medicine's Annual Meeting, Dr. Anthony Odibo cautions that cervical length screening, while valuable, should not be made standard of care.


Watch Point: Cervical Length Screeing Should Be Standard of Care


So, there’s definite evidence over the last 15 years that a short cervix is a good predictor of preterm birth. The only issue was, for many years, we did not really have an effective intervention for treating women who we identified to have a short cervix. Until a recently completed trial which was the senior author, at least the main first author was Hassan, Sonia Hassan, and we were part of the collaboration for that study.

So, the study used vaginal progesterone to treat women who were found to have a short cervical length, and we compared them to a group of women who had a similarly short cervical length who had not treatment. And the conclusion was that progesterone has almost a 45% effect in reducing preterm birth, which was really a fantastic finding.

So, following that study, most people are now suggesting that maybe we should universally screen women during pregnancy for a short cervix using transvaginal ultrasound. So the point of Dr. Hassan in that debate was that it’s ready for prime time. And my point… I took the notion that it’s not quite ready yet.

There’s a very thin line there, because I wasn’t categorically saying we’re not ready yet, I was just saying that prior to rolling it out universally, there are still certain things that we need to work through. Some of those factors include, first of all, easy access of women to the transvaginal ultrasound. At big university centers like ours, like Wayne State University, and I’m from Washington University in St. Louis, it’s very easy to implement this kind of training because we have many ultrasound rooms, we have the resources to be able to provide this vaginal probe, it’s a special transducer you use for this exam. However, you have to sterilize them in between patients, so it affects the flow of patients through your ultrasound suite.  So one of the points I was making is that in a small practice where you have just one room, and you’re doing OB-routinely, you’re doing OB ultrasound-it may be hard for someone in this kind of practice to universally screen their patients. Obviously with time, most people will find a way around that, either by investing more or looking for ways to at least, maybe, refer such patients for this kind of screening. So that was one point.

The other point has to do with quality assurance, or making sure that people measure the cervical length the way we did in these studies. Because if you go out and measure the cervical length in very random ways, sometimes people may start putting women on the medication that may not really need it, and then people may think that they did not benefit from the medication. So, those are some of the issues.

There’s also the issue of making sure that insurance companies cover the use of this technology. Currently we have published, together with Dr. Romero, and Hassan, a cost effectiveness analysis that showed that screening women universally is cost-saving, not just cost-effective but cost-saving. The problem… the question is whether such implementation would be universally covered by our insurance right now.

So, those are some of the few caveats we’re putting out there right now, just as notes of caution. You have to do it in a strict way, because we’ve had problems in the past in medical communities where a study shows some medication or some treatment to be beneficial, but when you start using it clinical practice, you don’t find that much benefit because they don’t stick to the same guidelines, and the strict guidelines, like they used during the study period.

So, at least going out, we want to make sure that this kind of assurance, quality assurance processes are in place before you start doing this universally.