Obstet Gynecol. 2021 Jun 1;137(6):e145-e162. doi: 10.1097/AOG.0000000000004397.
The incidence of multifetal gestations in the United States has increased dramatically over the past several decades. For example, the rate of twin births increased 76% between 1980 and 2009, from 18.9 to 33.3 per 1,000 births (1). However, after more than three decades of increases, the twin birth rate declined 4% during 2014-2018 to 32.6 twins per 1,000 total births in 2018 (2). The rate of triplet and higher-order multifetal gestations increased more than 400% during the 1980s and 1990s, peaking at 193.5 per 100,000 births in 1998, followed by a modest decrease to 153.4 per 100,000 births by 2009 (3). The triplet and higher-order multiple birth rate was 93.0 per 100,000 births for 2018, an 8% decline from 2017 (101.6) and a 52% decline from the 1998 peak (193.5) (4). The long-term changes in the incidence of multifetal gestations has been attributed to two main factors: 1) a shift toward an older maternal age at conception, when multifetal gestations are more likely to occur naturally, and 2) an increased use of assisted reproductive technology (ART), which is more likely to result in a multifetal gestation (5). A number of perinatal complications are increased with multiple gestations, including fetal anomalies, preeclampsia, and gestational diabetes. One of the most consequential complications encountered with multifetal gestations is preterm birth and the resultant infant morbidity and mortality. Although multiple interventions have been evaluated in the hope of prolonging these gestations and improving outcomes, none has had a substantial effect. The purpose of this document is to review the issues and complications associated with twin, triplet, and higher-order multifetal gestations and present an evidence-based approach to management.
美国多胎妊娠的发生率在过去几十年中急剧增加。例如，1980 年至 2009 年期间，双胞胎出生率增加了 76%，从每 1000 例活产 18.9 例增加到 33.3 例（1）。然而，在经历了三十多年的增长后，2014 年至 2018 年期间，双胞胎出生率下降了 4%，2018 年每 1000 例总分娩中有 32.6 对双胞胎（2）。三胞胎及以上多胎妊娠的发生率在 20 世纪 80 年代和 90 年代增加了 400%以上，1998 年达到每 10 万例 193.5 例的峰值，随后略有下降，2009 年降至每 10 万例 153.4 例（3）。2018 年三胞胎及以上多胎妊娠的发生率为每 10 万例 93.0 例，比 2017 年下降 8%（101.6），比 1998 年的峰值下降 52%（193.5）（4）。多胎妊娠发生率的长期变化归因于两个主要因素：1）受孕时产妇年龄趋于老龄化，多胎妊娠更有可能自然发生；2）辅助生殖技术（ART）的使用增加，这更有可能导致多胎妊娠（5）。多胎妊娠会增加许多围产期并发症，包括胎儿畸形、子痫前期和妊娠糖尿病。多胎妊娠中最严重的并发症之一是早产，以及由此导致的婴儿发病率和死亡率。尽管已经评估了许多干预措施，以期延长这些妊娠并改善结局，但没有一种干预措施有显著效果。本文的目的是回顾与双胞胎、三胞胎和更高序多胎妊娠相关的问题和并发症，并提出一种基于证据的管理方法。
