Pattinson Robert C, Cuthbert Anna, Vannevel Valerie
Department of Obstetrics and Gynaecology, University of Pretoria, Kalafong Hospital, Private Bag X396, Pretoria, Gauteng, South Africa, 0001.
Cochrane Pregnancy and Childbirth Group, Department of Women's and Children's Health, The University of Liverpool, First Floor, Liverpool Women's NHS Foundation Trust, Crown Street, Liverpool, UK, L8 7SS.
Cochrane Database Syst Rev. 2017 Mar 30;3(3):CD000161. doi: 10.1002/14651858.CD000161.pub2.
Pelvimetry assesses the size of a woman's pelvis aiming to predict whether she will be able to give birth vaginally or not. This can be done by clinical examination, or by conventional X-rays, computerised tomography (CT) scanning, or magnetic resonance imaging (MRI).
To assess the effects of pelvimetry (performed antenatally or intrapartum) on the method of birth, on perinatal mortality and morbidity, and on maternal morbidity. This review concentrates exclusively on women whose fetuses have a cephalic presentation.
We searched Cochrane Pregnancy and Childbirth Group's Trials Register (31 January 2017) and reference lists of retrieved studies.
Randomised controlled trials (including quasi-randomised) assessing the use of pelvimetry versus no pelvimetry or assessing different types of pelvimetry in women with a cephalic presentation at or near term were included. Cluster trials were eligible for inclusion, but none were identified.
Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. We assessed the quality of the evidence using the GRADE approach.
Five trials with a total of 1159 women were included. All used X-ray pelvimetry to assess the pelvis. X-ray pelvimetry versus no pelvimetry or clinical pelvimetry is the only comparison included in this review due to the lack of trials identified that examined other types of radiological pelvimetry or that compared clinical pelvimetry versus no pelvimetry.The included trials were generally at high risk of bias. There is an overall high risk of performance bias due to lack of blinding of women and staff. Two studies were also at high risk of selection bias. We used GRADEpro software to grade evidence for our selected outcomes; for caesarean section we rated the evidence low quality and all the other outcomes (perinatal mortality, wound sepsis, blood transfusion, scar dehiscence and admission to special care baby unit) as very low quality. Downgrading was due to risk of bias relating to lack of allocation concealment and blinding, and imprecision of effect estimates.Women undergoing X-ray pelvimetry were more likely to have a caesarean section (risk ratio (RR) 1.34, 95% confidence interval (CI) 1.19 to 1.52; 1159 women; 5 studies; low-quality evidence). There were no clear differences between groups for perinatal outcomes: perinatal mortality (RR 0.53, 95% CI 0.19 to 1.45; 1159 infants; 5 studies; very low-quality evidence), perinatal asphyxia (RR 0.66, 95% CI 0.39 to 1.10; 305 infants; 1 study), and admission to special care baby unit (RR 0.20, 95% CI 0.01 to 4.13; 288 infants; 1 study; very low-quality evidence). Other outcomes assessed were wound sepsis (RR 0.83, 95% CI 0.26 to 2.67; 288 women; 1 study; very low-quality evidence), blood transfusion (RR 1.00, 95% CI 0.39 to 2.59; 288 women; 1 study; very low-quality evidence), and scar dehiscence (RR 0.59, 95% CI 0.14 to 2.46; 390 women; 2 studies; very low-quality evidence). Again, no clear differences were found for these outcomes between the women who received X-ray pelvimetry and those who did not. Apgar score less than seven at five minutes was not reported in any study.
AUTHORS' CONCLUSIONS: X-ray pelvimetry versus no pelvimetry or clinical pelvimetry is the only comparison included in this review due to the lack of trials identified that used other types or pelvimetry (other radiological examination or clinical pelvimetry versus no pelvimetry). There is not enough evidence to support the use of X-ray pelvimetry for deciding on mode of delivery in women whose fetuses have a cephalic presentation. Women who undergo an X-ray pelvimetry may be more likely to have a caesarean section.Further research should be directed towards defining whether there are specific clinical situations in which pelvimetry can be shown to be of value. Newer methods of pelvimetry (CT, MRI) should be subjected to randomised trials to assess their value. Further trials of X-ray pelvimetry in cephalic presentations would be of value if large enough to assess the effect on perinatal mortality.
骨盆测量旨在评估女性骨盆大小，以预测其是否能够经阴道分娩。这可以通过临床检查、传统X线、计算机断层扫描（CT）或磁共振成像（MRI）来完成。
评估骨盆测量（产前或产时进行）对分娩方式、围产期死亡率和发病率以及孕产妇发病率的影响。本综述仅关注胎儿为头先露的女性。
我们检索了Cochrane妊娠与分娩组试验注册库（2017年1月31日）以及检索到的研究的参考文献列表。
纳入随机对照试验（包括半随机试验），这些试验评估骨盆测量与不进行骨盆测量的效果，或评估足月或接近足月时头先露女性不同类型的骨盆测量。整群试验符合纳入标准，但未检索到。
两位综述作者独立评估试验是否纳入及偏倚风险，提取数据并检查其准确性。我们使用GRADE方法评估证据质量。
纳入了5项试验，共1159名女性。所有试验均使用X线骨盆测量评估骨盆。由于未检索到研究其他类型放射学骨盆测量或比较临床骨盆测量与不进行骨盆测量的试验，本综述仅纳入了X线骨盆测量与不进行骨盆测量或临床骨盆测量的比较。纳入的试验总体偏倚风险较高。由于女性和工作人员未设盲，存在较高的实施偏倚风险。两项研究还存在较高的选择偏倚风险。我们使用GRADEpro软件对选定结局的证据进行分级；对于剖宫产，我们将证据评为低质量，而所有其他结局（围产期死亡率、伤口感染、输血、切口裂开和入住特殊护理婴儿病房）均为极低质量。降级是由于与缺乏分配隐藏和设盲相关的偏倚风险以及效应估计的不精确性。接受X线骨盆测量的女性更有可能进行剖宫产（风险比（RR）1.34，95%置信区间（CI）1.19至1.52；1159名女性；5项研究；低质量证据）。两组围产期结局无明显差异：围产期死亡率（RR 0.53，95%CI 0.19至1.45；1159名婴儿；5项研究；极低质量证据）、围产期窒息（RR 0.66，95%CI 0.39至1.10；305名婴儿；1项研究）和入住特殊护理婴儿病房（RR 0.20，95%CI 0.01至4.13；288名婴儿；1项研究；极低质量证据）。评估的其他结局包括伤口感染（RR 0.83，95%CI 0.26至2.67；288名女性；1项研究；极低质量证据）、输血（RR 1.00，95%CI 0.39至2.59；288名女性；1项研究；极低质量证据）和切口裂开（RR 0.59，95%CI 0.14至2.46；390名女性；2项研究；极低质量证据）。同样，接受X线骨盆测量的女性与未接受的女性在这些结局上未发现明显差异。任何研究均未报告5分钟时阿氏评分低于7分的情况。
由于未检索到使用其他类型骨盆测量（其他放射学检查或临床骨盆测量与不进行骨盆测量）的试验，本综述仅纳入了X线骨盆测量与不进行骨盆测量或临床骨盆测量的比较。没有足够的证据支持在胎儿为头先露的女性中使用X线骨盆测量来决定分娩方式。接受X线骨盆测量的女性可能更有可能进行剖宫产。应进一步研究确定是否存在骨盆测量具有价值的特定临床情况。新的骨盆测量方法（CT、MRI）应进行随机试验以评估其价值。如果足够大以评估对围产期死亡率的影响，对头先露女性进行X线骨盆测量的进一步试验将具有价值。
