When you think of a procedure like the TAC (transabdominal cerclage), you may think that it is a standardized operation. In fact, each surgeon has his or her own techniques, informed by their teachers and developed over their years of experience. So while there are some basics that are common to all TACs, the procedure itself can actually vary quite a bit.
So what are the defining characteristics of a TAC? What makes a TAC a TAC? Technically, there’s only one:
A TAC must be placed via an abdominal incision. If a surgeon tells you a TAC can be placed vaginally, he/she is either misleading you or very much mistaken. Either way, steer clear. A TAC is a transABDOMINAL cerclage, and can only be placed through an abdominal incision.
For the record, when I say “TAC” throughout this blog, I mean a cerclage that is placed via an abdominal incision and tied as a band around the internal os of the cervix at the cervicoisthmic junction. This has been proven to be the most effective form of TAC so far, although any cerclage that is placed through an abdominal incision is technically a TAC.
There are several areas where TACs differ:
Remember, this incision is NOT on your uterus, only on the outside. We’ve established that all TACs must be placed abdominally. Traditionally, this has meant through an open incision in the abdomen (laparotomy). Most of the time the incision is a low transverse incision — a horizontal line at about the level of your pubic hairline. Sometimes, however, there might be a reason for a vertical incision. If a surgeon does all of his placements vertically by default, I personally might consider seeing somebody else, as that type of incision makes recovery more difficult (in addition to creating a nasty scar). Sometimes a Pfannenstiel type incision has been used, but that is not as popular these days. Alternately, many surgeons now place TACs laparoscopically, or via several tiny incisions in the abdomen. This can be done with or without the DaVinci robot, but the incisions should be about the same regardless.
Here are a few examples of incisions:
There are three possibilities here:
- 5 mm mersilene tape. This is probably the most common option. Mersilene is a nonabsorbable braided polyester suture. It is sterile, inert, and nonreactive, so it should be able to stay in your body indefinitely without causing any problems. It’s incredibly strong, and could essentially support the weight of a grown man jumping on it.
- Neonatal/IV tubing. I only know of this being used in Australia. Tubing — either neonatal tubing or IV tubing — is used the same way as mersilene tape. As far as I know, success rates are similar.
- Nylon suture material. This is not recommended. It is strong, but much more likely to erode into the tissue of your cervix.
Suture Type/ Knot Placement
Some surgeons use curved needles to thread the band behind the cervix, but some prefer to use a more blunt instrument like clamps. Most surgeons placing a TAC traditionally tie the knot posteriorly (behind the cervix), I believe, to avoid problems with bladder adhesions and irritation. (One paper I read said tying the knot posteriorly allows the TAC to be removed, theoretically, through the vagina in a procedure called a culdotomy, in which the vaginal wall is cut in order to access the knot via the rectouterine pouch. I have never heard of this being done.) However, the knot is sometimes anterior (in front of the cervix) when placed laparoscopically without the DaVinci robot. The knot is usually a square knot, but surgeons may have their own variations.
Most variations here are minor and don’t make a lot of difference. There are a couple, though, that potentially make a big difference.
- I have heard of surgeons tying the band lateral to the uterine arteries, instead of medial to them, but that is a mistake (as opposed to a preference), and can lead to erosion into the arteries and bleeding.
- Some surgeons don’t tie a band around the cervix at all, but instead stitch through the cervix. One example is a surgeon who makes an abdominal incision and places a modified Shirodkar stitch at the internal os. This, in my opinion, should not be done, as it is more susceptible to problems with erosion and more likely to cause damage to the cervix, and ultimately, more likely to fail. If you’re going to undergo major surgery, you might as well have the best, safest solution, which is a band tied around the internal os of your cervix.
This encompasses all the other variations that might exist between surgeons. Some prefer only in-pregnancy, while some only do pre-pregnancy. Some have a strong preference for traditional, laparoscopic, or robotic laparoscopic. There are a lot of different approaches to anesthesia and pain management. Some doctors prefer spinal anesthesia in pregnancy, some always place the TAC under general anesthesia. Some prescribe ibuprofen for pain management, while others tell you never to take ibuprofen in pregnancy. There isn’t a clearly right way to do most of these things, and very experienced, very successful doctors have different opinions. Do your own research and decide who you want to trust based on that.