Nurture Fertility, Division of Obstetrics & Gynaecology, School of Clinical Sciences, University of Nottingham, United Kingdom.
Eur J Obstet Gynecol Reprod Biol. 2013 Jun;168(2):121-8. doi: 10.1016/j.ejogrb.2012.12.030. Epub 2013 Jan 22.
We performed a systematic review and meta-analysis to examine whether a difficult embryo transfer or the presence of blood on the transfer catheter affects assisted reproduction outcomes. We searched the following databases: Cochrane Central Register of Controlled Trials (CENTRAL), Database of Abstracts of Reviews of Effects (DARE), MEDLINE, Embase, PsycINFO, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS). We aimed to determine the risk ratio (RR) associated with difficult embryo transfer or the presence of blood on the transfer catheter for the following outcomes: live birth, clinical pregnancy, and miscarriage. We identified 3066 papers, of which 194 were reviewed and nine were included. The outcome of live birth was not reported in any of the included studies and the effect on miscarriage was too imprecise for any conclusions. Pooled analysis of five studies demonstrated lower clinical pregnancy rates following a non-easy embryo transfer (RR=0.75; 95% CI=0.66-0.86). This included three studies showing subjectively difficult transfers reducing clinical pregnancies (RR=0.67; 95% CI=0.51-0.87) and two studies in which the need for additional manoeuvers reduced clinical pregnancies (RR=0.78; 95% CI=0.67-0.91). The presence of blood on the transfer catheter did not affect clinical pregnancy rates (RR=0.96; 95% CI=0.82-1.14) in five studies. We concluded that low quality evidence suggests that a difficult embryo transfer but not a bloody catheter reduces the chance of achieving a clinical pregnancy. More good quality studies are needed to evaluate the effect of difficult embryo transfer and the presence of blood on the catheter on the main outcomes of assisted reproduction.
我们进行了系统评价和荟萃分析，以研究困难的胚胎移植或移植导管上有血是否会影响辅助生殖的结果。我们检索了以下数据库： Cochrane 对照试验中心注册库（CENTRAL）、疗效评价文摘数据库（DARE）、医学文献在线数据库（MEDLINE）、Embase、PsycINFO、护理学及相关健康科学文献累积索引（CINAHL）和拉丁美洲及加勒比健康科学文献数据库（LILACS）。我们旨在确定困难的胚胎移植或移植导管上有血与以下结局相关的风险比（RR）：活产、临床妊娠和流产。我们共识别出 3066 篇论文，其中 194 篇进行了综述，9 篇被纳入。纳入的研究均未报告活产结局，而流产结局的影响结果过于不精确，无法得出任何结论。五项研究的汇总分析显示，非易移胚胎移植后临床妊娠率较低（RR=0.75；95% CI=0.66-0.86）。这包括三项研究表明主观上困难的转移减少了临床妊娠（RR=0.67；95% CI=0.51-0.87），以及两项研究中需要额外的操作减少了临床妊娠（RR=0.78；95% CI=0.67-0.91）。五项研究均表明，移植导管上有血并不影响临床妊娠率（RR=0.96；95% CI=0.82-1.14）。我们的结论是，低质量证据表明，困难的胚胎移植而不是带血的导管会降低实现临床妊娠的机会。需要更多高质量的研究来评估困难的胚胎移植和导管上有血对辅助生殖主要结局的影响。
