探讨剖宫产术后阴道分娩(VBAC)产妇的母儿结局。

选择2016年1月1日至2019年12月31日，四川大学华西第二医院收治的VBAC足月妊娠产妇397例为研究对象，纳入研究组。按照1∶1比例，采用随机数字表法随机抽取同期于本院足月经阴道分娩的非瘢痕子宫产妇397例，作为对照，纳入对照组。观察2组产妇年龄、身高、人体质量指数(BMI)、本次分娩距前次分娩间隔时间、分娩时孕龄，第一、第二、第三产程时间，术中出血量、产后出血(PPH)量(2 h)、PPH率、严重PPH率，以及新生儿出生体重与窒息发生率等指标，并采用成组t检验、Wilcoxon秩和检验、χ²检验和Fisher确切概率法对上述指标进行统计学比较。对2016—2019年本院产妇分娩情况进行分析。2组产妇年龄、身高、BMI、分娩时孕龄等一般临床资料比较，差异均无统计学意义(P>0.05)。本研究遵循的程序符合2013年新修订的《世界医学协会赫尔辛基宣言》要求。

①2016—2019年，本院剖宫产术分娩率为58.45%～62.37%，剖宫产术后瘢痕子宫(SUAC)患者再次妊娠的剖宫产术分娩率为93.06%～95.83%，平均为94.60%(10 942/11 567)，非SUAC患者的剖宫产术分娩率为50.27%(18 586/36 972)。瘢痕子宫患者为13 963例(28.77%)，2017年瘢痕子宫患者所占比例最高，为33.74%(3 361/9 961)，此后呈下降趋势。②研究组产妇第一、第二产程时间及术中出血量、PPH量(2 h)、PPH率分别为363 min(212～450 min)、46 min(22～60 min)、312 mL(200～350 mL)、348 mL(230～380 mL)、10.8%(43/397)，均显著长于、大于、高于对照组的294 min(180～380 min)、15 min(7～20 min)、231 mL(150～280 mL)、264 mL(180～310 mL)、4.3%(17/397)，研究组新生儿出生体重为(3 216±359) g，则显著低于对照组的(3 369±369) g，并且差异均有统计学意义(Z＝4.797、16.065、8.028、8.122，χ²＝12.188，t＝-17.013，均为P<0.001)。③SUAC患者再次妊娠的子宫破裂发生率为1.73/10 000(2/11 567)，占VBAC者的0.32%(2/625)。

VBAC是可行的，子宫破裂发生率低，但是其PPH风险增加。临床对于此类产妇，产程中应做好监护，积极预防PPH。

To explore maternal and fetal outcomes of parturients with vaginal delivery after cesarean section (VBAC).

From January 1, 2016 to December 31, 2019, a total of 397 full-term parturients with VBAC in West China Second University Hospital, Sichuan University were selected as research subjects and included in study group. According to the ratio of 1∶1, 397 cases of full-term multiparas with non-scarred uterus who gave birth via vagina during the same period in the same hospital were randomly selected as control and enrolled into control group by random number table method. The age, height, body mass index (BMI), interval between this delivery and the previous delivery, gestational age at delivery, duration of the first, second and third stages of labor, amounts of intraoperative hemorrhage and postpartum hemorrhage (PPH) (2 h), incidences of PPH and severe PPH, and neonatal birth weight and incidence of neonatal asphyxia were observed in two groups and were compared by independent-samples t test, chi-square test and Fisher exact probability method. The delivery situation of parturients in our hospital from 2016 to 2019 was analyzed. There were no significant differences in general clinical data, such as maternal age, height, BMI and gestational age at delivery between two groups (P>0.05). The procedures followed in this study were conformed to requirements of World Medical Association Declaration of Helsinki revised in 2013.

①From 2016 to 2019, delivery rate of cesarean section in cases collected hospital was 58.45% to 62.37%. In re-pregnancy of patients with scarred uterus after cesarean section (SUAC), delivery rate of cesarean section was 93.06% to 95.83%, with an average of 94.60% (10 942/11 567), and delivery rate of cesarean section for patients without SUAC was 50.27% (18 586/36 972). There were 13 963 (28.77%) patients with scarred uterus, and the proportion of scarred uterus patients was highest in 2017, which was 33.74% (3 361/9 961), and then decreased. ②In study group, durations of the first and second stages of labor, amount of intraoperative hemorrhage, amount of PPH (2 h) after delivery, and incidence of PPH were 363 min (212- 450 min), 46 min (22-60 min), 312 mL (200-350 mL), 348 mL (230-380 mL) and 10.8% (43/397) respectively, which were significantly longer, larger and higher than those of control group 294 min (180-380 min), 15 min (7-20 min), 231 mL (150-280 mL), 264 mL (180-310 mL) and 4.3% (17/397), and neonatal birth weight in study group was (3 216±359) g, which was statistically lower than that of (3 369±369) g in control group, and all differences were statistically significant (Z=4.797, 16.065, 8.028, 8.122, χ²=12.188, t=-17.013; all P<0.001). ③The incidence of uterine rupture was 1.73/10 000 (2/11 567) in re-pregnancy of patients with SUAC, which accounted for 0.32% (2/625) in parturients with VBAC.

VBAC is feasible, and the incidence of uterine rupture is low, but the risk of PPH increases. Therefore, clinical care should be taken during labor to actively prevent PPH of these patients.