School of Biomedical Sciences, The University of Queensland, St Lucia, Queensland, Australia.
School of Biomedical Sciences, The University of Queensland, St Lucia, Queensland, Australia; Child Health Research Centre, The University of Queensland, South Brisbane, Queensland, Australia.
Am J Obstet Gynecol. 2021 Dec;225(6):607.e1-607.e22. doi: 10.1016/j.ajog.2021.06.078. Epub 2021 Jun 26.
A systematic review was conducted to determine placental outcomes following prenatal alcohol exposure in women.
The search terms "maternal OR prenatal OR pregnant OR periconception" AND "placenta" AND "alcohol OR ethanol" were used across 5 databases (PubMed, Embase, Cochrane Library, Web of Science, and CINAHL) from inception until November 2020.
Articles were included if they reported placental outcomes in an alcohol exposure group compared with a control group. Studies were excluded if placentas were from elective termination before 20 weeks' gestation, animal studies, in vitro studies, case studies, or coexposure studies.
Study quality was assessed by 2 reviewers using the Newcastle-Ottawa Quality Assessment Scale. Title and abstract screening was conducted by 2 reviewers to remove duplicates and irrelevant studies. Remaining full text articles were screened by 2 reviewers against inclusion and exclusion criteria. Placental outcome data were extracted and tabulated separately for studies of placentation, placental weight, placental morphology, and placental molecular studies. Meta-analyses were conducted for outcomes reported by >3 studies.
Database searching retrieved 640 unique records. Screening against inclusion and exclusion criteria resulted in 33 included studies. The quality assessment identified that 61% of studies were high quality, 30% were average quality, and 9% were low quality. Meta-analyses indicated that prenatal alcohol exposure increased the likelihood of placental abruption (odds ratio, 1.48; 95% confidence interval, 1.37-1.60) but not placenta previa (odds ratio, 1.14; 95% confidence interval, 0.84-1.34) and resulted in a reduction in placental weight of 51 g (95% confidence interval, -82.8 to -19.3). Reports of altered placental vasculature, placental DNA methylation, and gene expression following prenatal alcohol exposure were identified. A single study examined placentas from male and female infants separately and found sex-specific placental outcomes.
Prenatal alcohol exposure increases the likelihood of placental abruption and is associated with decreased placental weight, altered placental vasculature, DNA methylation, and molecular pathways. Given the critical role of the placenta in determining pregnancy outcomes, further studies investigating the molecular mechanisms underlying alcohol-induced placental dysfunction are required. Sex-specific placental adaptations to adverse conditions in utero have been well documented; thus, future studies should examine prenatal alcohol exposure-associated placental outcomes separately by sex.
系统综述旨在确定女性产前酒精暴露对胎盘结局的影响。
检索了 5 个数据库（PubMed、Embase、Cochrane 图书馆、Web of Science 和 CINAHL），使用了“产妇或产前或怀孕或围孕期”和“胎盘”和“酒精或乙醇”的搜索词，时间跨度从建库至 2020 年 11 月。
如果报告了酒精暴露组与对照组的胎盘结局，则纳入研究。排除在 20 周妊娠前选择性终止妊娠的胎盘、动物研究、体外研究、病例研究或共同暴露研究。
由 2 名评审员使用纽卡斯尔-渥太华质量评估量表评估研究质量。标题和摘要筛选由 2 名评审员进行，以去除重复和不相关的研究。对剩余的全文文章，由 2 名评审员根据纳入和排除标准进行筛选。分别对胎盘形成、胎盘重量、胎盘形态和胎盘分子研究的胎盘结局数据进行提取和制表。对报告超过 3 项研究的结果进行了荟萃分析。
数据库检索得到 640 条独特记录。根据纳入和排除标准进行筛选后，纳入 33 项研究。质量评估确定，61%的研究为高质量，30%为中等质量，9%为低质量。荟萃分析表明，产前酒精暴露增加了胎盘早剥的可能性（优势比，1.48；95%置信区间，1.37-1.60），但不会增加前置胎盘（优势比，1.14；95%置信区间，0.84-1.34），胎盘重量减少 51 克（95%置信区间，-82.8 至-19.3）。报告了产前酒精暴露后胎盘血管改变、胎盘 DNA 甲基化和基因表达的改变。一项研究分别检查了男性和女性婴儿的胎盘，发现了胎盘的性别特异性结局。
产前酒精暴露增加了胎盘早剥的可能性，并与胎盘重量减轻、胎盘血管改变、DNA 甲基化和分子途径改变相关。鉴于胎盘在决定妊娠结局方面的关键作用，需要进一步研究酒精引起的胎盘功能障碍的分子机制。在宫内环境中，对不利条件的胎盘性别特异性适应已有充分的文献记载；因此，未来的研究应该分别按性别检查与产前酒精暴露相关的胎盘结局。
