Rotational forceps: a retrospective study evaluating anatomical and functional consequences for the pelvic floor

Diagnosis of Levator Ani Muscle Avulsion in Instrumented Delivery: Meta-analysis

“…Five studies were retrospective and the rest prospective. The ultrasound examination was performed in most studies within 6 months after delivery [11][12][13][14][15][16][17]19,20,22,23,[25][26][27][28][29][30][31][32][33][34][35], though some performed an ultrasound examination only or also after this period [17,18,21,24,35,36]. Some papers included a small number of VDs [12,20,27] and FDs [12][13][14]27], a possible source of bias.…”

“…The majority of articles that specified the type of vacuum used in the RV reported that a metal vacuum bird's cup was 50 mm [19,[24][25][26]29,30,[32][33][34], although one of them also assessed LAM avulsion after a Kiwi vacuum was used [32]. The majority of studies on FD described the rates of LAM avulsion with Kielland's forceps [28][29][30][31]33,34,36], though one of them studied Anderson forceps and Wrigley forceps [19].…”

“…uum, with an OR of 0.977 (0.426; 2.241; p = 0.957) and an adjusted OR of 2.90 (0.691; 12.20; p = 0.146). Something similar was true of the studies that specified the type of forceps used during the FD, as most describe the rate of LAM avulsion caused by only one type of forceps (Kielland's forceps) [28][29][30][31]33,34,36]. Only one study included different forceps [19], with a small number of participants (20 Anderson forceps and 22 Wrigley forceps), and did not compare the rate of LAM avulsion between the two types.…”

“…Only five studies studied the rate of LAM avulsion according to the way in which the instrument was applied during instrumented delivery [26,28,29,33,36]. It was determined that the number of vacuum tractions necessary to complete the fetal extraction was not associated with a higher rate of LAM avulsion [26], nor was the position of the fetal head (anterior, posterior, or transverse) at the time of vacuum application [26].…”

“…There was no asymmetry in the funnel plot in the rank correlation (p = 0.39) or in the regression test (p = 0.86). 4.93) [36]. One study analyzed whether the disarticulation of the forceps before the delivery of the fetal head could benefit the rate of LAM, and it found a crude OR (without disengagement vs. disengagement) for avulsion of 0.90 (95% CI 0.49-1.67; p = 0.757) and an adjusted OR (adjusted for maternal age, induced labor, epidural period, second stage of labor, perineal tear, and fetal head circumference) of 0.82 (95% CI 0.40-1.69; p = 0.603) [31].…”