Preterm birth, defined as birth before 37 weeks of gestation, poses a significant challenge in obstetrics and contributes substantially to neonatal complications and mortality. One underlying cause of preterm birth is cervical insufficiency, a condition where the cervix painlessly dilates and thins prematurely during the second or early third trimester of pregnancy. This can lead to pregnancy loss or very early delivery. For specific cases of cervical insufficiency, a specialized intervention known as a transabdominal cerclage offers a highly effective approach to support the pregnancy.
Defining Transabdominal Cerclage
A transabdominal cerclage (TAC) involves placing a strong, permanent stitch high on the cervix, close to the internal os. This band is made of a non-absorbable synthetic material, such as Mersilene tape. Its primary purpose is to provide robust mechanical support to the cervix, preventing premature widening under increasing pregnancy pressure.
The stitch is positioned at a level of the cervix not easily reached vaginally, necessitating an abdominal surgical method. Unlike other cervical stitches, the TAC is a permanent fixture, remaining in place through subsequent pregnancies. This procedure offers a secure solution for challenging forms of cervical insufficiency.
When a TAC is Indicated
A transabdominal cerclage is reserved for situations where other interventions are less effective. It is considered for individuals with a history of recurrent late miscarriage or very preterm birth due to cervical insufficiency. A primary indication for a TAC is a prior failed transvaginal cerclage.
It is also recommended for a very short or absent cervix, significant cervical scarring, or anatomical challenges that make a transvaginal approach impractical. A thorough evaluation of the patient’s medical history and cervical anatomy determines the need for a TAC.
The TAC Surgical Procedure
The transabdominal cerclage procedure can be performed through an open abdominal incision or, more commonly, using a minimally invasive laparoscopic or robotic approach. The open method involves a small bikini-line incision. Laparoscopic or robotic techniques use smaller incisions, leading to reduced recovery time. The procedure is often performed before pregnancy, known as an interval placement, allowing optimal band placement for support.
In some cases, a TAC can be placed during early pregnancy, though pre-pregnancy placement is preferred due to lower risks. During surgery, a non-absorbable suture is guided around the cervix at the internal os and secured, creating a tight band that holds the cervix closed. This permanent stitch remains in place for future pregnancies.
TAC vs. Transvaginal Cerclage: Key Differences
The transabdominal cerclage (TAC) differs from a transvaginal cerclage (TVC) in several ways, influencing their applications. A primary distinction is stitch placement: a TAC is positioned high on the cervix near the internal os, an area not easily accessible vaginally, while a TVC is placed lower. This higher placement provides a more robust and secure closure.
Another key difference is permanence; the TAC is a permanent suture for multiple pregnancies, while a TVC is temporary and removed before delivery. The surgical approach also varies: a TAC requires an abdominal incision, while a TVC is performed vaginally. These distinctions mean a TAC is reserved for complex cases of cervical insufficiency, especially when a TVC has failed or a vaginal approach is unfeasible.
Life After a TAC: Outcomes and Care
Individuals who undergo a transabdominal cerclage can expect a high success rate in preventing preterm birth. TAC surgery is effective in 95% to 98% of patients, leading to deliveries at 36 weeks or later. This high success rate lowers the chance of preterm birth and the need for neonatal intensive care compared to transvaginal cerclage.
Delivery via Cesarean section is required, as the permanent stitch remains in place. The TAC remains for future pregnancies, offering ongoing support. While rare, complications can include bladder injury or infection at the incision site. Patients experience minimal recovery time and do not require bed rest or activity modification during pregnancy. The long-term outlook for women with a TAC is positive.
anatomical challenges that make a transvaginal approach impractical or ineffective. Conditions such as a cervical tear from a previous delivery or surgical removal of large portions of the cervix can also lead to the need for a TAC. The choice to proceed with a TAC depends on a thorough evaluation of the patient’s medical history and cervical anatomy.
The TAC Surgical Procedure
The transabdominal cerclage procedure can be performed either through an open abdominal incision or, more commonly today, using a minimally invasive laparoscopic or robotic approach. The open method typically involves a small bikini-line incision, similar to a C-section incision but smaller. Laparoscopic or robotic techniques involve smaller incisions, which can lead to reduced recovery time. The procedure is often performed before pregnancy, known as an interval placement, allowing the surgeon to place the band as high as possible on the cervix for optimal support.
In some cases, a TAC can be placed during early pregnancy, typically around 8 to 14 weeks, though pre-pregnancy placement is generally preferred due to lower risks. During the surgery, a non-absorbable suture, such as a 5mm Mersilene tape, is guided around the cervix at the level of the internal os. The suture is then secured, creating a tight band that holds the cervix closed. The stitch is designed to be permanent and remains in place for future pregnancies, eliminating the need for removal after delivery.
TAC vs. Transvaginal Cerclage: Key Differences
The transabdominal cerclage (TAC) differs from a transvaginal cerclage (TVC) in several fundamental ways, influencing their respective applications. A primary distinction lies in the placement of the stitch: a TAC is positioned high on the cervix near the internal os, an area not easily accessible vaginally, while a TVC is placed lower on the cervix. This higher placement in a TAC provides a more robust and secure closure.
Another key difference is permanence; the TAC is a permanent suture designed to remain in place through multiple pregnancies, whereas a TVC is typically temporary and removed before delivery. The surgical approach also varies significantly: a TAC requires an abdominal incision (open or laparoscopic), while a TVC is performed through the vagina. These distinctions mean a TAC is usually reserved for complex cases of cervical insufficiency, such as when a TVC has failed or cervical anatomy makes a vaginal approach unfeasible, positioning the TVC as a more common first-line option.
Life After a TAC: Outcomes and Care
Individuals who undergo a transabdominal cerclage can generally expect a high success rate in preventing preterm birth. Studies indicate that TAC surgery is effective in 95% to 98% of patients, leading to deliveries at 36 weeks or later. This high success rate contributes to a lower chance of preterm birth and the associated need for neonatal intensive care compared to transvaginal cerclage.
A significant aspect of managing pregnancy with a TAC is the typical requirement for delivery via Cesarean section, as the permanent stitch remains in place. The TAC can remain in place for future pregnancies, offering ongoing support without additional procedures. While generally safe, potential, though rare, complications can include bladder injury during the procedure or infection at the incision site. Patients typically experience minimal recovery time after the procedure, often around two weeks, and usually do not require bed rest or activity modification during pregnancy. The long-term outlook for women with a TAC is generally positive, emphasizing the importance of ongoing medical care to support healthy pregnancy outcomes.