Malmström vacuum or Kielland forceps: which causes more damage to pelvic floor?

Impact of the type of vaginal assisted delivery on the pelvic floor and OASI - Ultrasound study

OBJECTIVE

To assess the prevalence of pelvic floor and anal sphincter trauma in women after assisted vaginal delivery.

METHODS

Retrospective study on 201 primiparous women after assisted vaginal delivery, control group 43 women after normal vaginal delivery. 4D translabial ultrasound examination of the levator ani and the anal sphincter was performed according to standard methodology at least 3 months postpartum. Ultrasound classification of trauma was performed by two independent evaluators blinded to clinical data. A third evaluator was asked to confirm findings in case of discrepancy.

RESULTS

The LAM avulsion rate for normal delivery was 20.9%, for forceps 60%, for vacuum extraction 21.7% Odds ratio for forceps vs. NVD was 4.32 (1.69, 11.01), for vacuum vs. NVD 0.98 (0.409, 2.327). Ultrasound OASI rate was 33.3% for Forceps and 30.50% for Vacuum. This equated to an OR of 1.78 (0.85 - 3.10) for Forceps and 1.62 (0.85-3.10) for Vacuum relative to NVD.

CONCLUSIONS

Our data confirm forceps as the major risk factor for levator avulsion. Forceps also implies a non-significantly higher risk of OASI compared to NVD.

Maternal and neonatal morbidity after forceps or spatulas-assisted delivery in preterm birth

OBJECTIVE

The aim of this study was to assess perinatal morbidity associated with spatulas or forceps assisted delivery in preterm birth.

STUDY DESIGN

This is a retrospective cohort study including all women with assisted deliveries on singleton pregnancy in cephalic presentation, before 37 weeks of gestation, in two tertiary care centers. We compared forceps-assisted deliveries with spatula-assisted deliveries. The main outcome was the rate of neonatal birth trauma. Secondary outcomes included other neonatal parameters, maternal outcomes and obstetric anal sphincter injuries.

RESULTS

Out of 37 002 deliveries, 59 (0.2 %) preterm assisted deliveries with forceps and 111 (0.3%) preterm spatulas deliveries were included. The rate of neonatal birth trauma was low for both devices, without significant difference (3.4% in Forceps group vs 0.9% in Spatulas group, p = 0.28). The rate of episiotomy was 79.7% after forceps-assisted delivery and 48.6% for spatulas (p < 0.001). The rate of obstetric anal sphincter injuries was 1.7% and 2.7% respectively (p = 0,9).

CONCLUSION

The rate of birth trauma was low in both forceps-assisted deliveries and spatula-assisted deliveries and was not significantly different between the two groups.

Ultrasonic Diagnosis and Analysis of the Effect of Labor Analgesia on Early Pelvic Floor Function and Pelvic Floor Dysfunction

Pelvic floor dysfunction disease (PFD) is a common pelvic organ dysfunction disease in the clinic of obstetrics and gynecology. Its cause is mainly the damage, defects and dysfunction of the pelvic floor support structure. Not only is the pathogenesis complicated, but also various symptoms coexist, which seriously affects the physical and mental health of female patients. Mechanical injury of the pelvic floor fascia tissue and levator ani muscles is the anatomical basis of PFD after birth; early postpartum pelvic floor examination and treatment can prevent and control the occurrence or development of PFD. Spinal canal anesthesia has good analgesic effect during labor and delivery, has little effect on mothers and infants, and is widely used. However, there are few domestic and foreign reports on the effect of labor analgesia on the pelvic floor. Labor analgesia relaxes the pelvic floor muscles, unblocks the birth canal, and the influence on the pelvic floor muscles is worth exploring. Based on the pelvic floor muscle strength screening to understand the changes in the function of the pelvic floor muscles, combined with the three-dimensional pelvic floor ultrasound examination, the pelvic floor structure and the levator ani muscle are clearly imaged, and the pelvic floor muscle structure is evaluated in the natural state and the analgesic muscle relaxation state. This study used a combination of the two to evaluate the effect of labor analgesia on pelvic floor function of primiparous women; provide individualized intervention treatment for high-risk groups screened; provide clinical basis for the prevention and treatment of PFD.

Comparison of maternal and neonatal outcomes after forceps or spatulas-assisted delivery

OBJECTIVE

The aim of this study was to compare the perinatal outcomes associated with spatulas or forceps assisted delivery.

STUDY DESIGN

This is a bicentric retrospective cohort study including all assisted deliveries in cephalic presentation after 37 weeks of gestation, performed on singleton pregnancy with forceps and with spatulas in two tertiary centers. The main outcome was the rate of episiotomy. Secondary outcomes included obstetric anal sphincter injuries (OASIS), maternal outcomes and neonatal parameters.

RESULTS

Out of 37 002 deliveries, the overall rate of assisted delivery was 11.4 %, and 1 041 (2.8 %) assisted deliveries with forceps and 2 462 (6.7 %) spatulas deliveries were included. The rate of episiotomy was 90.3 % after forceps-assisted delivery and 70.9 % for spatulas (p < 0.001). The rate of OASIS was 7.2 % and 5.6 % respectively (p = 0.06). A slight but significant decrease in neonatal trauma after spatulas was observed.

CONCLUSION

In this retrospective cohort study, the episiotomy rate was higher with forceps assisted deliveries than with spatulas. Both instruments have low neonatal morbidity and are similar regarding OASIS.

Type of levator ani muscle avulsion as predictor for the disappearance of avulsion

OBJECTIVES

The objective of our study was to establish whether the type of levator ani muscle (LAM) avulsion diagnosed 6 months after delivery influences the integrity of the LAM at 1 year after delivery and determine its influence on the levator hiatus area.

STUDY DESIGN

This observational prospective cohort study included 192 primiparous women with vaginal delivery. Transperineal ultrasound examinations were performed at 6 months and 1 year postpartum. Levator hiatus measurements (anteroposterior diameter, transverse diameter, and area) were performed in the plane of minimal dimensions. Complete avulsion was defined based on maximum contraction in multislice mode. Type I LAM avulsion was present when most lateral fibers of the pubovisceral muscle were observed at its insertion at the pubic level (the arch of the elevator remained intact). Type II LAM avulsion was defined as a complete detachment of the pubovisceral muscle from its insertion at the pubic level.

RESULTS

In total, 192 patients were recruited after delivery; 48 patients were diagnosed with complete LAM avulsion, and 13 patients with avulsion did not attend the second ultrasound follow-up at 1 year after delivery. Thirty-five patients with complete LAM avulsion were included in the study. At 6 months after delivery, 51 LAM avulsions were observed in 35 patients (including bilateral LAM avulsion in 16 cases), of which 54.9% were right avulsions and 45.1% left avulsions. Furthermore, 11 (five right and six left) were type I LAM avulsions at the 6-month assessment, and all of these had disappeared 1 year after delivery. However, none of the type II LAM avulsions (23 right and 17 left) observed at 6 months had disappeared at the second ultrasound examination. There were no differences between the LAM areas detected at the first and second ultrasound examinations (10.2 ± 3.3 vs 9.3 ± 1.8; P = .404).

CONCLUSIONS

The type of LAM avulsion observed at 6 months after childbirth predicts LAM persistence at 1 year postpartum.

Association between sexual dysfunction and avulsion of the levator ani muscle after instrumental vaginal delivery

INTRODUCTION

The effects of levator ani muscle (LAM) avulsion after instrumental delivery on the sexual function of patients are currently unknown. Therefore, the objective of our study was to use a validated questionnaire, namely, the Female Sexual Function Index (FSFI), to compare the sexual function in patients with and without LAM avulsion after instrumental vaginal delivery.

MATERIAL AND METHODS

This was a prospective observational study of 112 primiparous women after instrumental (vacuum or forceps) vaginal delivery. The obstetric and general characteristics of the population were studied. At 6 months postpartum, the contraceptive method used and the occurrence of LAM avulsion (using four-dimensional transperineal ultrasound) were determined, and the FSFI was administered.

RESULTS

A total of 100 patients (62 without avulsion and 38 with avulsion) completed the study. Thirty-eight (38%) were diagnosed with avulsion (42.1% after Kielland forceps delivery, 57.9% after Malmström vacuum delivery; P = .837). Women with LAM avulsion had significantly lower scores for desire (2.9 ± 1.2 vs 3.4 ± 1.1; P = .049), arousal (2.8 ± 1.7 vs 3.6 ± 1.4; P = .014), lubrication (2.3 ± 1.4 vs 3.0 ± 1.2; P = .011), orgasm (2.6 ± 1.6 vs 3.3 ± 1.2; P = .006) and satisfaction (3.1 ± 1.8 vs 3.9 ± 1.5; P = .051) than did women without LAM avulsion. The overall FSFI score was lower in patients with avulsion (16.7 ± 8.9 vs 20.7 ± 6.9, P = .033). These results were obtained after controlling for confounders (delivery mode, induced labor, birthweight, perineal tears, avulsion degree, contraceptive method and group assignment for the parent study) in the multivariate analysis (F = 4.974, P = .001).

CONCLUSIONS

Patients with LAM avulsion present a higher degree of sexual dysfunction compared wiith patients without avulsion at 6 months after instrumental vaginal delivery.

Prevalence of levator hiatal overdistension after vacuum and forceps deliveries

INTRODUCTION

Levator ani avulsion rates after assisted vaginal delivery have been reported in the literature. However, there are no definitive data regarding the association between overdistention and assisted vaginal delivery. Therefore, our aim is to report overdistention rates after assisted vaginal delivery with a postpartum ultrasound examination.

MATERIALS AND METHODS

This multicenter study involved a retrospective analysis of data from primiparous women (n = 602) who had previously been recruited at three tertiary hospitals between January 2015 and January 2017. Overdistention was assessed at 6 months postpartum using three-/four-dimensional transperineal ultrasound. Patients with levator ani muscle avulsion were excluded. Overdistention was defined as a levator hiatal area ≥ 25 cm² on Valsalva.

RESULTS

Of the 602 primiparous patients, 250 patients who satisfied the inclusion criteria (139 patients who underwent forceps delivery and 111 patients who underwent vacuum delivery) were evaluated. Overdistention occurred in 20% (50 of 250) of these patients. Overdistention was observed for 1% (1/111) of vacuum deliveries and 35.3% (49 of 139) of forceps deliveries. We found an increased risk of overdistention following forceps delivery compared to vacuum delivery, with a crude odds ratio (OR) of 59.9 (95% confidence interval [CI]: 8.1, 442.2) and an adjusted OR (adjusted for maternal age, second-stage duration, and head circumference) of 17.6 (95% CI: 2.3, 136.7).

CONCLUSIONS

Postpartum overdistention occurred for 20% of assisted vaginal deliveries, with an increased risk of overdistention following forceps delivery compared to vacuum delivery.