The Department of Obstetrics and Gynecology, Chaim Sheba Medical Center, Ramat-Gan, Israel.
The Department of Obstetrics and Gynecology, Hadassah-Hebrew University Medical Center, POB 12000, Jerusalem, Israel.
Arch Gynecol Obstet. 2020 Jun;301(6):1423-1429. doi: 10.1007/s00404-020-05558-7. Epub 2020 May 3.
To evaluate the association of sonographic fetal head circumference (HC) with obstetric anal sphincter injury (OASIS) occurrence among primiparous women who underwent vacuum-assisted delivery (VAD).
A retrospective study of all primiparous women who delivered at term by VAD between 2011 and 2019 and underwent ultrasound with fetal biometry within 1 week prior to delivery. Women who suffered OASIS were compared to women without OASIS.
Overall, 74 of 3222 (2.3%) primiparous women suffered an OASIS. As compared with control, women with OASIS were younger (median 28 vs. 30 years, p = 0.001), had higher BMI (median 28.2 vs. 26.9 kg/m, p = 0.03), and had a longer second stage of labor (median 190 vs. 168 min, p = 0.01). Fetal head circumference was larger in the OASIS group (mean 334 vs. 330 mm, p = 0.03), occiput posterior fetal head position was more prevalent (12 (16%) vs. 232 (7.4%), OR [95% CI]: 2.43 (1.29-4.57), p = 0.004), and the rate of mediolateral episiotomy performed was lower (58 (78.0%) vs. 2777 (88.2%), OR [95% CI]: 0.48 (0.27-0.85), p = 0.01). Multivariate regression modeling identified higher fetal HC (aOR [95% CI] 1.03 (1.001-1.06), p = 0.04) and occiput posterior (aOR [95% CI] 2.5 (1.16-5.71), p = 0.01) as independently positively associated with OASIS. Mediolateral episiotomy and maternal age were independently negatively associated with an OASIS (aOR [95% CI] 0.39 (0.18-0.85), p = 0.01); aOR [95% CI] 0.4 (0.17-0.60), p = 0.001).
Sonographic large fetal HC is associated with OASIS occurrence during VAD. The only modifiable predictor of OASIS detected was mediolateral episiotomy, found to be protective against OASIS.
评估初产妇行真空辅助分娩（VAD）时超声胎儿头围（HC）与产科肛门括约肌损伤（OASIS）发生的相关性。
这是一项回顾性研究，纳入了 2011 年至 2019 年期间行 VAD 足月分娩且在分娩前 1 周内行胎儿生物测量超声检查的初产妇。比较 OASIS 组与无 OASIS 组。
总体而言，3222 名初产妇中有 74 名（2.3%）发生 OASIS。与对照组相比，OASIS 组产妇年龄更小（中位数 28 岁 vs. 30 岁，p=0.001）、BMI 更高（中位数 28.2 千克/平方米 vs. 26.9 千克/平方米，p=0.03）、第二产程更长（中位数 190 分钟 vs. 168 分钟，p=0.01）。OASIS 组胎儿头围更大（均值 334 毫米 vs. 330 毫米，p=0.03），枕后位胎儿头位更常见（12 例（16%） vs. 232 例（7.4%），OR [95%CI]：2.43 [1.29-4.57]，p=0.004），行正中切开术的比例较低（58 例（78.0%） vs. 2777 例（88.2%），OR [95%CI]：0.48 [0.27-0.85]，p=0.01）。多变量回归模型确定了更高的胎儿 HC（aOR [95%CI] 1.03 [1.001-1.06]，p=0.04）和枕后位（aOR [95%CI] 2.5 [1.16-5.71]，p=0.01）与 OASIS 独立正相关。正中切开术和产妇年龄与 OASIS 独立负相关（aOR [95%CI] 0.39 [0.18-0.85]，p=0.01）；aOR [95%CI] 0.4 [0.17-0.60]，p=0.001）。
超声胎儿头围大与 VAD 期间发生 OASIS 相关。唯一检测到的 OASIS 可改变预测因素是正中切开术，其可预防 OASIS。
