Medical research that neither influences clinical practice nor helps to improve people's lives could be considered an expensive waste of time. A co-ordinated team science approach is critical to ensuring patient-centred research ideas are carefully honed, meticulously executed and ultimately translated into measurable improvements in human health (1). Several studies published in this issue of BJOG emphasise the importance of diverse multidisciplinary teams for ensuring complementary expertise, effective problem-solving and innovation in research.

A systematic review by Ewington and colleagues found that none of the 111 published models to predict fetal macrosomia and large for gestational age are ready for clinical implementation. Most of the 58 included studies were at high risk of bias, few models had been externally validated and some used predictors that are not routinely measured in clinical practice, rendering them impracticable for clinical translation. In his associated mini-commentary, Jack Wilkinson asserts that teams with appropriate methodological expertise to guide model design, analysis and reporting are key to preventing research waste. He points out that models developed using flawed methods may actually do more harm than good and notes the essential gatekeeping role journals play by refusing to publish studies that lack methodological rigour.

Other research featured in this issue of BJOG includes a propensity score-matched analysis of 50 565 singleton live births exploring the relationship between in utero aspirin exposure and child neurocognitive development by Zhu and colleagues. Their study found that second trimester aspirin exposure was associated with improved child neurocognitive development. Sharp and colleagues found no improvement in 2-year neurodevelopmental outcomes in infants whose mothers were treated with sildenafil during severe early-onset fetal growth restriction pregnancies. They conclude that sildenafil should not be prescribed for this condition. Ghandhi and colleagues showed in a retrospective cohort study that antenatal pyelonephritis admissions are decreasing in the USA, however, those hospitalised have a higher risk for sepsis and severe maternal morbidity. Socio-economic deprivation was shown to be associated with increased risk.

Sanders and colleagues assessed maternal and neonatal outcomes among spontaneous vaginal births occurring in and out of water following intrapartum water immersion in a cohort study of 73 229 women. They found no increased risk of obstetric anal sphincter injury (OASI) or adverse fetal outcomes, including fetal or neonatal death, neonatal unit admission with respiratory support or administration of antibiotics within 48 h of birth. The authors conclude that among women using intrapartum water immersion, remaining in the pool and giving birth in the water is as safe for mothers and their babies as leaving the water before birth.

Prasad and colleagues share the results from their international cross-sectional survey of 113 clinicians involved in the management of monochorionic diamniotic twin pregnancies with selective fetal growth restriction. They conclude that there is significant variation in clinician attitudes to the management of these pregnancies, especially for type II and type III cases, highlighting the need for evidence based clinical guidelines to support a consistent approach to patient care.

Haem and colleagues present a systematic review of six studies including 412 pregnancies in women with vascular Ehlers-Danlos syndrome. They found an elevated risk of uterine rupture, vascular events, digestive events and death during pregnancy with the highest risk during the peripartum period. They recommend that the patient's cardiologist initiates treatment with beta blockers and monitors for aortic dilatation in pregnancy. The authors assert that to avoid expulsive efforts, a caesarean section should be scheduled at 37 weeks.

Tang and colleagues report the results of their prospective cohort study assessing fasting blood glucose as a screening measure for late-onset diabetes in the third trimester. They found 6.3% of a 1130 singleton cohort who had a normal gestational diabetes mellitus screen in the first and second trimester were found to have late onset gestational diabetes mellitus by additional fasting blood glucose screening at 32–24 weeks. This research further documents an association between elevated fasting blood glucose in late pregnancy and adverse perinatal outcomes including macrosomia and neonatal intensive care unit admission.

Latt and colleagues present a population-based record linkage cohort study evaluating postpartum haemorrhage (PPH) and risk of cardiovascular disease in later life. They show in a cohort of 70 904 women that 25 177 women had at least one PPH. They found that having at least one PPH was associated with a near two-fold increased risk of developing cardiovascular disease in the first year after birth, with residual increased risk continuing for up to 15 years after giving birth.

A review of the current evidence for cervical cerclage by Story and Shennan highlights many important clinical questions that have not yet been addressed by research. They recommend good quality evidence from large RCTs to assess which women would most likely benefit from cervical cerclage and how it should be optimally performed.

In a descriptive study of the International Network on Cancer, Infertility and Pregnancy Registry, Heimovaara and colleagues found that 5.6% of women diagnosed with cancer during pregnancy died. Lung cancer, gastro-oesophageal cancer and acute leukaemia had the highest rates of maternal mortality. Maternal death was associated with fewer live births, more elective caesarean sections, lower gestational age and more preterm births. The authors conclude that the early identification of women at risk of cancer-related death in pregnancy allows for a fair discussion with the woman and her partner, and the initiation of adequate palliative care including psychological support for the family that experience a maternal death.

In this issue of BJOG, Huang and colleagues describe the current global burden of vaginal cancer with 17 908 newly reported cases in 2020 and highest age-standardised rates in south-central Asia and southern Africa. The most significant rising trends were seen in the UK, Chile and Bahrain. Targeted interventions, including HPV vaccination and education, particularly in regions with a lower human development index and a higher prevalence of HPV infection, are needed to reverse these trends.

Almadori and colleagues present a scoping review showing limited evidence that reconstructive surgery improves quality of life, satisfaction with vulval appearance and sexual function in survivors of female genital mutilation. They conclude that high quality clinical trials are now warranted to confirm these findings.

Fayyad and Hasan describe the laparoscopic mid-urethral autologous rectus fascial sling (LMAFS) technique to treat female stress urinary incontinence necessitated by the serious concerns being raised over the safety of vaginal mesh tapes. All ten patients who underwent this procedure report cure from stress urinary incontinence with normal voiding at 12 month review. The benefit of this technique is its minimal access approach and avoidance of over tightening of the sling.

Levin and colleagues undertook a bibliometric analysis of USA publications indexed in pubmed over five decades on the topic of abortion and showed significantly higher numbers of funded studies, publications and scholarly impact of those publications in states that protect abortion care versus those with more restrictive policies. The observed disparities may be amplified by the recent Supreme Court ruling and subsequent new anti-abortion legislations in many US states.

Finally, Crawford and colleagues offer some hope for improved ovarian cancer detection by measuring serum HE4 alongside CA125.

既不影响临床实践也不帮助改善人们生活的医学研究可以被认为是昂贵的时间浪费。协调一致的团队科学方法对于确保以患者为中心的研究理念得到精心打磨、精心执行并最终转化为人类健康的可衡量改善至关重要 （1）。本期 BJOG 上发表的几项研究强调了多元化多学科团队对于确保互补专业知识、有效解决问题和研究创新的重要性。

Ewington 及其同事的一项系统评价发现，已发表的 111 个预测巨大儿和大于胎龄儿的模型均未准备好用于临床实施。纳入的 58 项研究中的大多数存在高偏倚风险，很少有模型经过外部验证，并且一些使用了临床实践中未常规测量的预测因子，因此无法用于临床转化。在他的相关迷你评论中，Jack Wilkinson 断言，具有适当方法专业知识来指导模型设计、分析和报告的团队是防止研究浪费的关键。他指出，使用有缺陷的方法开发的模型实际上弊大于利，并指出期刊拒绝发表缺乏方法严谨性的研究，从而发挥了重要的把关作用。

本期 BJOG 中的其他研究包括 Zhu 及其同事对 50 565 名单胎活产婴儿的倾向评分匹配分析，探讨了宫内阿司匹林暴露与儿童神经认知发展之间的关系。他们的研究发现，孕中期接触阿司匹林与儿童神经认知发育的改善有关。Sharp 及其同事发现，在严重的早发性胎儿生长受限妊娠期间，母亲接受西地那非治疗的婴儿的 2 年神经发育结局没有改善。他们得出的结论是，西地那非不应该用于治疗这种情况。Ghandhi 及其同事在一项回顾性队列研究中表明，美国的产前肾盂肾炎入院率正在下降，但是，住院患者患败血症和严重孕产妇发病率的风险更高。社会经济剥夺被证明与风险增加有关。

Sanders 及其同事在一项涉及 73 229 名妇女的队列研究中评估了产时浸水中后自然阴道分娩在水中和水中发生的母体和新生儿结局。他们发现产科肛门括约肌损伤 （OASI） 或不良胎儿结局的风险没有增加，包括胎儿或新生儿死亡、新生儿病房入住呼吸支持或出生后 48 小时内使用抗生素。作者得出结论，在使用产时浸水的妇女中，留在游泳池中并在水中分娩对母亲和婴儿来说与出生前离开水一样安全。

Prasad 及其同事分享了他们对 113 名参与选择性胎儿生长受限的单绒毛膜双胎妊娠管理的临床医生的国际横断面调查的结果。他们得出的结论是，临床医生对这些妊娠管理的态度存在显着差异，尤其是对于 II 型和 III 型病例，这凸显了基于证据的临床指南支持一致患者护理方法的必要性。

Haem 及其同事对 6 项研究进行了系统评价，其中包括 412 例血管性 Ehlers-Danlos 综合征女性妊娠。他们发现怀孕期间子宫破裂、血管事件、消化事件和死亡的风险升高，围产期的风险最高。他们建议患者的心脏病专家开始使用 β 受体阻滞剂进行治疗，并监测妊娠期的主动脉扩张。作者断言，为避免排宫产，应安排在 37 周时进行剖宫产。

Tang 及其同事报告了他们的前瞻性队列研究的结果，该研究评估了空腹血糖作为妊娠晚期迟发性糖尿病的筛查措施。他们发现，在妊娠早期和妊娠中期妊娠糖尿病筛查正常的 1130 例单例队列中，有 6.3% 的人在妊娠早期和 24 周通过额外的空腹血糖筛查发现患有晚发性妊娠糖尿病。这项研究进一步证实了妊娠晚期空腹血糖升高与不良围产期结局（包括巨大儿和新生儿重症监护病房收治）之间的关联。

Latt 及其同事提出了一项基于人群的记录连锁队列研究，评估了产后出血 （PPH） 和晚年心血管疾病的风险。他们在 70 904 名女性的队列中表明，25 177 名女性至少患有一次 PPH。他们发现，至少患有一次 PPH 与出生后第一年患心血管疾病的风险增加近两倍有关，残留的风险增加在分娩后持续长达 15 年。

Story 和 Shennan 对宫颈环扎术当前证据的回顾强调了许多尚未通过研究解决的重要临床问题。他们推荐了来自大型 RCT 的高质量证据，以评估哪些女性最有可能从宫颈环扎术中受益，以及如何进行宫颈环扎术。

在国际癌症、不孕症和妊娠登记网络的一项描述性研究中，Heimovaara 及其同事发现，在怀孕期间被诊断患有癌症的妇女中，有 5.6% 死亡。肺癌、胃食管癌和急性白血病的孕产妇死亡率最高。孕产妇死亡与活产率较低、选择性剖宫产率较高、胎龄较低和早产率较高有关。作者得出结论，早期识别有癌症相关死亡风险的妊娠期妇女，可以与妇女及其伴侣进行公平的讨论，并开始适当的姑息治疗，包括为经历孕产妇死亡的家庭提供心理支持。

在本期 BJOG 中，Huang 及其同事描述了当前全球阴道癌的负担，2020 年新报告了 17 908 例病例，中南亚和南部非洲的年龄标准化率最高。英国、智利和巴林的上升趋势最为显著。需要有针对性的干预措施，包括 HPV 疫苗接种和教育，特别是在人类发展指数较低和 HPV 感染患病率较高的地区，以扭转这些趋势。

Almadori 及其同事提出了一项范围审查，显示有限的证据表明重建手术可以提高女性生殖器切割幸存者的生活质量、对外阴外观和性功能的满意度。他们得出的结论是，现在需要高质量的临床试验来证实这些发现。

Fayyad 和 Hasan 描述了腹腔镜尿道中段自体直肌筋膜悬吊术 （LMAFS） 技术，用于治疗女性压力性尿失禁，这是由于对阴道网带安全性的严重担忧所必需的。所有接受该手术的 10 名患者在 12 个月回顾时都报告了压力性尿失禁治愈且排尿正常。这种技术的好处是它的进入方法最小，避免了吊索的过度拧紧。

Levin 及其同事对 pubmed 上索引的美国出版物进行了五十年来关于堕胎主题的文献计量分析，结果显示，与政策更严格的州相比，在保护堕胎护理的州，这些出版物的资助研究、出版物和学术影响力的数量要高得多。观察到的差异可能会因最近的最高法院裁决和随后美国许多州的新反堕胎立法而被放大。

最后，Crawford 及其同事通过测量血清 HE4 和 CA125 为改善卵巢癌检测提供了一些希望。