Sapra Katherine J, Joseph K S, Galea Sandro, Bates Lisa M, Louis Germaine M Buck, Ananth Cande V
1 Department of Epidemiology, Joseph L. Mailman School of Public Health, Columbia University, New York, NY, USA.
2 Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Rockville, MD, USA.
Reprod Sci. 2017 Apr;24(4):502-513. doi: 10.1177/1933719116654994. Epub 2016 Sep 27.
Approximately one-third of pregnancies end in loss; however, the natural history of early pregnancy loss, including signs and symptoms preceding loss, has yet to be fully described and its underlying mechanisms fully understood. We searched PubMed/MEDLINE and Embase to identify articles with prospective ascertainment of signs and symptoms, including vaginal bleeding, nausea, and vomiting, of pregnancy loss < 20 weeks gestation in spontaneous conceptions to ascertain existing literature on symptomatology of pregnancy loss. Two preconception and 16 pregnancy cohort studies that ascertained information on bleeding and/or nausea/vomiting prior to pregnancy loss ascertainment were included. Data from these studies indicated increased risk of loss with vaginal bleeding and decreased risk of loss with nausea/vomiting, though these studies were mostly comprised of pregnancies surviving into late first trimester. While such associations are biologically plausible, these study designs are subject to bias, given recruitment of women at later gestational ages and reliance on women presenting to care. Reporting symptoms to clinicians and over long periods may introduce reporting error. Data gaps remain regarding (1) relationships between signs and symptoms and losses occurring very early, prior to care entry; (2) empirical testing of whether relationships between signs and symptoms and loss differ across gestational age; (3) whether similar relationships between signs and symptoms and loss are observed in populations using assisted reproductive technologies; (4) the patterning of multiple signs and symptoms in relation to loss; and (5) how hormonal and physiologic adaptions to early pregnancy relate to symptomatology and pregnancy loss.
大约三分之一的妊娠以流产告终；然而，早期流产的自然史，包括流产前的体征和症状，尚未得到充分描述，其潜在机制也未被完全理解。我们检索了PubMed/MEDLINE和Embase，以确定有关前瞻性确定自然受孕中妊娠<20周流产的体征和症状（包括阴道出血、恶心和呕吐）的文章，以确定现有关于流产症状学的文献。纳入了两项孕前队列研究和16项妊娠队列研究，这些研究在确定流产前确定了有关出血和/或恶心/呕吐的信息。这些研究的数据表明，阴道出血会增加流产风险，恶心/呕吐会降低流产风险，尽管这些研究大多包括存活至孕早期晚期的妊娠。虽然这些关联在生物学上是合理的，但鉴于纳入的是孕龄较大的女性且依赖前来就诊的女性，这些研究设计容易产生偏差。向临床医生报告症状以及长时间报告可能会引入报告误差。关于以下方面的数据空白仍然存在：（1）在进入医疗保健之前非常早期出现的体征和症状与流产之间的关系；（2）对体征和症状与流产之间的关系是否因孕龄而异进行实证检验；（3）在使用辅助生殖技术的人群中是否观察到体征和症状与流产之间的类似关系；（4）多种体征和症状与流产相关的模式；以及（5）激素和生理对早期妊娠的适应如何与症状学和流产相关。
