摘要
【研究背景】在包括社会心理因素在内的多种因素影响下,我国许多地区剖宫产率逐年上升。已有研究表明围产死亡率的下降并不直接依赖于剖宫产率的升高。关于剖宫产术利弊之争没有一致结论,而既往研究中没有充分考虑与均衡剖宫产与阴道分娩两组间孕产妇本身医学条件及其它危险因素的差别,两组产妇产后健康结局的差别也许归结于引起剖宫产分娩的因素所致,而不是分娩方式本身所导致的结果。因而需要开展设计合理的专项研究以客观评价剖宫产术本身对母婴健康的影响。
【研究目的】研究剖宫产术对产妇和婴儿健康的影响。具体包括:1.剖宫产术是否会影响妇女产后感染、贫血、抑郁等病症的发生;2.剖宫产术是否影响妇女产后性生活恢复的时间;3.剖宫产术是否会影响婴儿疾病的发生;4.剖宫产术是否会影响婴儿发育状况;5.剖宫产术是否会影响产后母乳喂养。
【内容方法】采用前瞻性流行病学研究设计,以剖宫产术指征为配比因素招收剖宫产、阴道分娩两组对象,采用结构式问卷、量表、实验室检测项目与定性研究相结合的方式,调查产妇基线情况,比较两组产妇产后近期状况以及产后1月、6月、12月三次随访的健康相关状况。统计分析策略主要包括:分层分析、二项式回归模型、倾向评分法、线性混合模型、广义估计方程、加权最小二乘法以及生存分析法。
【研究结果】2001年5月~2003年2月在上海市三个妇幼保健院共招收了602例合格研究对象,剖宫产、阴道分娩两组各为301例,2004年3月产后1年随访完毕,失访累计13例(2.2%)。通过两次筛查及配比招收研究对象,剖宫产、阴道分娩两组对象基本人口学特征及孕产期特征多数均衡可比,一些不均衡的潜在混杂因素通过倾向评分法进行了分层调整。主要结果如下:
1.产后住院期间剖宫产组产妇并发症总计9.36%,是阴道分娩组的2.21倍(95%CI:1.12~4.37)。其中剖宫产组产后出血率为3.99%,是阴道分娩组的5.64倍(95%CI:1.19~26.87)。剖宫产、阴道分娩两组产后感染率分别为2.33%、1.00%,产后病率分别为4.32%、3.32%,差别没有统计学意义。
2.剖宫产组产后恶露干净时间延长,在各次随访期间两组对象疾病发生情况相似,没有发现产后贫血、伤口愈合不良、生殖道感染及因病住院方面的组间差别。但产后1年随访时发现剖宫产组发生慢性腹痛的危险性是阴道分
娩组的3.59倍(95%Cl:1.18一10.92)。
3.产后1个月时剖宫产、阴道分娩两组产妇产后抑郁发生率分别为1.“%、
0.66%,抑郁的发生与产前抑郁评分有关,而与分娩方式无关。产后6个月
时剖宫产、阴道分娩两组分别有95%、93%的对象恢复了产后性生活,两组
产妇产后性生活恢复的中位时间都是产后12周,产后性生活恢复时间的组
间差别没有统计学意义。
4.产后近期及各次随访期间未发现剖宫产、阴道分娩两组婴儿疾病发生方
面的差异,虽然产后1月因病住院的剖宫产儿比例相对要少,但从1年总计
情况来看两组婴儿因病住院比例的差别没有统计学意义。婴儿常见病1年总
计比较中发现剖宫产儿发生婴儿腹泻的危险是阴道分娩儿的1.25倍(95%CI:
1 .01一1 .56)。
5.剖宫产术与婴儿的体格生长发育没有关联,但剖宫产儿DDST测定总计
可疑数比例高于阴道分娩儿,可能影响婴儿将来的神经心理发育。
6.音IJ宫产组产后血清催乳素水平低于阴道分娩组,两组均值分别为
186.32林g/L(170.06一204.13林g/L)、211.13林g/L(198.11一225.00林g/L)。剖宫
产组产后泌乳始动时间、产后1月时乳量及产后各期母乳喂养率都晚于或低
于阴道分娩组。剖宫产组产后1年内母乳喂养失败的风险是阴道分娩组的
1 .21倍(95%Cl:1 .10一1.33),而脐血和初乳免疫球蛋白检测指标的组间差别都
没有统计学意义。
[结论]非绝对指征行剖宫产术对母婴健康的影响包括:1.剖宫产术增加
产后近期产妇并发症的发生率,主要是产后出血的增加;增加产后l年发生
慢性腹痛的危险性。2.剖宫产术与产后抑郁及产后性生活恢复时间没有关
联。3.产后近期,剖宫产术与婴儿疾病的发生没有关联,但增加产后1年
内婴儿腹泻发生的危险。4.剖宫产术对婴儿体格生长发育没有影响,可能
影响婴儿的神经心理发育。5.剖宫产术降低产妇催乳素的水平,降低产后
母乳喂养率。本研究显示非绝对指征行剖宫产术弊大于利,应当避免不必要
的产科干预,降低剖宫产率。
[BACKGROUND] Caesarean section is now the most frequently performed major obstetric operation in the P.R. China. Nearly half of Chinese babies is delivered by this operation in the urban areas. Most studies of caesarean section measuring benefits and risks of postpartum outcomes may have been biased, as women with medical or obstetric problems were more likely to have been selected for a caesarean section. Thus, the occurrence of adverse maternal or neonatal outcomes may have been due to the risk factors necessitating the caesarean section rather than to the procedure itself. One way to avoid this selection bias is to conduct a matched prospective cohort study in which women from the two groups would be matched on the indications of caesarean section.
[OBJECTIVES] To investigate maternal and infant's medical outcomes of subjects with caesarean section compared with those undergoing vaginal delivery.
[METHODS] We conducted a matched prospective cohort study of primiparas who delivered singleton at term and compared the maternal and infant's medical outcomes of women with caesarean section with those undergoing vaginal delivery at 1 month, 6 months, and 12 months postpartum.
[RESULTS] A total of 602 pregnant women were included in this prospective study. Baseline characteristics, birth records, and outcomes were investigated using self-designed questionnaires and the established psychological tests in gestational week 36 and above, 1 month, 6 months, and 12 months postpartum.
Caesarean section was associated with higher rates of postpartum morbidities compared with vaginal delivery (relative risk (RR) = 2.21; 95% confidence interval (CI): 1.12-4.37). The risk of hemorrhage was significantly higher in the caesarean group (RR = 5.64; 95% CI: 1.19-26.87), with no significant increase in the risk of puerperal fever or postpartum infection.
Postpartum depression occurred in 1.66% of women with caesarean section, which was similar to the incidence of 0.66% in women with vaginal delivery. Also, there was no significant difference in the resumption duration of sexual activities between the two groups.
The risk of chronic abdominal pain was significantly higher for caesarean section group (RR = 3.59; 95% CI: 1.18-10.92) than for vaginal delivery 12 months postpartum. The two groups had similar incidences of anemia and infectious complications such as wound infection and urinary tract infection.
Caesarean section was not associated with neonatal morbidity and later physical development. However, caesarean section was associated with a higher rate of diarrhea (RR = 1.25; 95% CI: 1.01-1.56) and a higher risk of suspicious results of DDST in infants.
There was a significantly lower postpartum PRL level in the caesarean section group (186.32ug/L, 95%CI: 170.06-204.\3\igfL) compared with vaginal delivery group (211.13ng/L, 95%CI: 198.1 l~225.00ug/L). Caesarean was a significant risk factor for breastfeeding initiation and remained an important hazard for a shorter duration of breastfeeding (RR =1.21; 95%CI: 1.10-1.33).
[CONCLUSIONS] Caesarean section was associated with higher rates of postpartum morbidities, especially hemorrhage and chronic abdominal pain 12 months postpartum. Caesarean section was not associated with the postpartum depression and resumption duration of sexual activities. Caesarean section was found to be associated with significantly lower postpartum PRL, lower rate of successful breastfeeding, and higher risk of diarrhea and suspicious results of DDST in infants although the effect on longer-term outcomes was uncertain. The findings provide additional evidence in support of the avoidance of unnecessary obstetric interventions.
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