Division of Gynaecology and Obstetrics, Oslo University Hospital, Oslo, Norway.
Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.
PLoS One. 2021 Nov 16;16(11):e0259926. doi: 10.1371/journal.pone.0259926. eCollection 2021.
Midpelvic vacuum extractions are controversial due to reports of increased risk of maternal and perinatal morbidity and high failure rates. Prospective studies of attempted midpelvic vacuum outcomes are scarce. Our main aims were to assess frequency, failure rates, labor characteristics, maternal and neonatal complications of attempted midpelvic vacuum deliveries, and to compare labor characteristics and complications between successful and failed midpelvic vacuum deliveries.
Clinical data were obtained prospectively from all attempted vacuum deliveries (n = 891) over a one-year period with a total of 6903 births (overall cesarean section rate 18.2% (n = 1258). Student's t-test, Mann-Whitney U-test or Chi-square test for group differences were used as appropriate. Odds ratios and 95% confidence intervals are given as indicated. The uni- and multivariable analysis were conducted both as a complete case analysis and with a multiple imputation approach. A p-value of <0.05 was considered statistically significant.
Attempted vacuum extractions from midpelvic station constituted 36.7% (n = 319) of all attempted vacuum extractions (12.9% (n = 891) of all births). Of these 319 midpelvic vacuum extractions, 11.3% (n = 36) failed and final delivery mode was cesarean section in 86.1% (n = 31) and forceps in the remaining 13.9% (n = 5). Successful completion of midpelvic vacuum by 3 pulls or fewer was achieved in 67.1%. There were 3.9% third-degree and no fourth-degree perineal tears. Cup detachments were associated with a significantly increased failure rate (adjusted OR 6.13, 95% CI 2.41-15.56, p< 0.001).
In our study, attempted midpelvic vacuum deliveries had relatively low failure rate, the majority was successfully completed within three pulls and they proved safe to perform as reflected by a low rate of third-degree perineal tears. We provide data for nuanced counseling of women on vacuum extraction as a second stage delivery option in comparable obstetric management settings with relatively high vacuum delivery rates and low cesarean section rates.
中骨盆真空提取因报告显示产妇和围产儿发病率增加以及高失败率而存在争议。中骨盆真空提取尝试结果的前瞻性研究很少。我们的主要目的是评估尝试中骨盆真空分娩的频率、失败率、分娩特征、母婴并发症，并比较成功和失败的中骨盆真空分娩的分娩特征和并发症。
在一年的时间里，我们前瞻性地从所有尝试的真空分娩（n=891）中获得临床数据，共有 6903 例分娩（总剖宫产率为 18.2%（n=1258）。使用学生 t 检验、Mann-Whitney U 检验或卡方检验进行组间差异比较。给出比值比和 95%置信区间。使用单变量和多变量分析进行完整病例分析和多重插补方法。p 值<0.05 被认为具有统计学意义。
中骨盆位置的真空提取尝试占所有真空提取尝试的 36.7%（n=319）（所有分娩的 12.9%（n=891））。在这 319 例中骨盆真空提取中，11.3%（n=36）失败，最终分娩方式为剖宫产 86.1%（n=31），其余 13.9%（n=5）为产钳。通过 3 次或更少的拉动成功完成中骨盆真空提取的比例为 67.1%。会阴三度撕裂的发生率为 3.9%，无四度撕裂。杯脱落与显著增加的失败率相关（调整后的 OR 6.13，95%CI 2.41-15.56，p<0.001）。
在我们的研究中，尝试中骨盆真空分娩的失败率相对较低，大多数在 3 次拉动内成功完成，并且由于会阴三度撕裂的发生率较低，证明实施是安全的。我们提供了有关中骨盆真空提取作为第二产程分娩选择的数据，这些数据适用于具有相对较高的真空分娩率和较低的剖宫产率的类似产科管理环境，为女性提供了细致的咨询。
