Letter to the Editor: Single- vs. Double-Layer Closure of Hysterotomy at the Time of Cesarean Delivery

To the editors,

We read with great interest the study of Bamberg et al. who randomized 435 women into three types of uterine closure at cesarean [1]. They observed that a double-layer closure with an unlocked first layer was associated with better scar healing compared to a single-layer closure regardless of whether the single layer was locked or unlocked. They have to be congratulated on obtaining follow-up at 6 months or more in almost 200 participants. They demonstrated the necessity of such follow-up (> 6 months) to obtain accurate evaluation of uterine scar healing. Moreover, we believe that strong conclusions can now be drawn from that study along with the cumulative evidence available in the literature.

First, they observed that locking or unlocking the first-layer closure was not associated with a significant difference in the remaining myometrial thickness (RMT). Second, their results confirmed that a double-layer closure with an unlocked first layer including only a “narrow band of the endometrial layer avoiding the involvement of large segments of the endometrium within the stitch” was associated with a greater RMT than any type of single-layer closure in women undergoing an elective or a primary cesarean delivery. A double-layer closure (median of 8.0 mm) was associated with an RMT approximately 1.3 – 1.4 mm greater than a single-layer closure (median of 6.6 for an unlocked and 6.7 mm for a locked suture) in women undergoing a primary cesarean. These observations are in agreement with our recent randomized trial in which we observed that women with a double-layer closure (with an unlocked first layer excluding the decidua) had a median RMT of 6.1 mm more than 6 months after cesarean, which was 2.4 mm greater than the median RMT of women with a locked single-layer closure including the decidua (3.8 mm) [2]. Altogether, these results suggest that a double-layer closure is beneficial for achieving optimal scar healing, but also that a greater benefit could be first obtained by avoiding inclusion of the decidua in the suture for the first layer.

Our trial was limited to women who underwent an elective primary cesarean, because a locked single layer and the absence of labor at the time of previous cesarean had been associated with greater risk of uterine rupture [2] [3] [4]. Bamberg et al. suggest that women undergoing primary or elective cesarean should have a double-layer closure. However, it could be difficult to identify the decidual layer when performing a cesarean in advanced labor when the low uterine segment is highly stretched and we are wondering whether uterine closure is as important in those cases. We would like to know whether Bamberg et al. observed an impact of uterus closure on RMT in women who underwent a primary cesarean during labor.

• References

• 1 Bamberg C. Dudenhausen JW. Bujak V. et al. A Prospective Randomized Clinical Trial of Single vs. Double Layer Closure of Hysterotomy at the Time of Cesarean Delivery: The Effect on Uterine Scar Thickness. Ultraschall in Med 2016; DOI: 10.1055/s-0042-112223.
• 2 Roberge S. Demers S. Girard M. et al. Impact of uterine closure on residual myometrial thickness after cesarean: a randomized controlled trial. Am J Obstet Gynecol 2016; 214: 507 e1-507 e6
• 3 Roberge S. Chaillet N. Boutin A. et al. Single- versus double-layer closure of the hysterotomy incision during cesarean delivery and risk of uterine rupture. Int J Gynaecol Obstet 2011; 115: 5-10
• 4 Algert CS. Morris JM. Simpson JM. et al. Labor before a primary cesarean delivery: reduced risk of uterine rupture in a subsequent trial of labor for vaginal birth after cesarean. Obstet Gynecol 2008; 112: 1061-1066