An updated practice bulletin from the American College of Obstetricians and Gynecologists on vaginal birth after cesarean delivery (VBAC) advises that 60% to 80% of women who attempt a trial of labor after cesarean delivery (TOLAC) achieve a successful vaginal birth.
"The best circumstance for a woman to labor after having had a prior [cesarean delivery] is when the balance of risks and chances of success are acceptable to both the patient and the physician, and that will be different in every case," Mark Turrentine, MD, chair of ACOG's Committee on Practice Bulletins-Obstetrics, said in a news release. "There are certain conditions that can make VBAC less likely if TOLAC is attempted, including advanced maternal age, a high body mass index, a high birth weight and a previous [cesarean delivery] that resulted because the cervix failed to dilate," Dr Turrentine explained.
ACOG's Committee on Practice Bulletins–Obstetrics, in collaboration with William Grobman, MD, published the new recommendations in the November issue of Obstetrics & Gynecology. The recommendations replace those published in August 2010.
"ACOG's recommendation is not meant to increase restrictions but instead ensure all women who want to attempt to undergo labor after a cesarean are in the appropriate facility to achieve positive outcomes," Dr Turrentine said. "If the necessary resources aren't available, obstetric care providers and patients need to discuss alternative options early in the course of antenatal care, including a transfer to another facility. However, this absolutely should not result in women having limited access to VBAC."
TOLAC should be performed at centers that are equipped to provide adequate care. "Because of the risks associated with TOLAC, and because uterine rupture and other complications may be unpredictable, ACOG recommends that TOLAC be attempted in facilities that can provide cesarean delivery for situations that are immediate threats to the life of the woman or fetus," the authors explain. "When resources for emergency cesarean delivery are not available, ACOG recommends that obstetricians or other obstetric care providers and patients considering TOLAC discuss the hospital's resources and availability of obstetric, pediatric, anesthesiology, and operating room staffs."
Women undergoing TOLAC should not attempt to deliver at home, as complications necessitating emergency medical care can be unpredictable.
The authors note that several advantages are associated with VBAC, including allowing women to avoid major abdominal surgery and lowering their risk for hemorrhage, blood clots, and infection. It also shortens the recovery period and reduces women's risk for experiencing maternal morbidity or mortality during delivery in a future pregnancy as a result of repeated cesarean deliveries.
The number of previous cesarean deliveries, the reasons for them, and the types of surgical incisions used should all be considered when making decisions regarding VBAC and TOLAC.
Most women with one previous cesarean delivery with a low-transverse incision are safe candidates for TOLAC. The guidelines address various previous surgical incisions and make recommendations regarding each. The authors stress the need to completely document the informed consent process.
Planned TOLAC is generally not recommended for women with high risk for uterine rupture and women in whom vaginal delivery is contraindicated, such as those with placenta previa.
Do not use misoprostol for cervical ripening or labor induction in term patients with prior cesarean delivery or major uterine surgery. Epidural analgesia for labor may be used during TOLAC.
"Women with one previous cesarean delivery with a low-transverse incision, who are otherwise appropriate candidates for twin vaginal delivery, are considered candidates for TOLAC," the authors explain.
"Induction of labor remains an option in women undergoing TOLAC."
External cephalic version of infants with breech presentation is not contraindicated in women with a prior low transverse uterine incision who are candidates for external cephalic version and TOLAC. These women should undergo continuous fetal heartrate monitoring during TOL.
Investigators began to reconsider the paradigm of performing successive cesarean deliveries during the 1970s as evidence supported TOLAC and VBAC, but uptake has been uneven.
"Despite a 23 percent increase in VBACs from 1985 to 1996, that number has since plummeted as the cesarean delivery rate has continued to trend upward," Dr Turrentine said. "This is the opposite of what we want to see happening, and it's because there is still a great deal of misunderstanding regarding the safety of TOLAC and VBAC and a reticence to consider this a viable option due to medical liability concerns."
The authors have disclosed no relevant financial relationships.
Obstet Gynecol. 2017;130:e217-e233. Abstract
Medscape Medical News © 2017 WebMD, LLC
Send comments and news tips to firstname.lastname@example.org.
Cite this: Troy Brown. Updated Guidelines on VBAC Released by ACOG - Medscape - Nov 07, 2017.