Table_2_Gestational Weight Gain and Its Effects on Maternal and Neonatal Outcome in Women With Twin Pregnancies: A Systematic Review and Meta-Analysis.docx

Background: The incidence of twin pregnancies has risen recently. Such pregnancies are associated with an increased risk for poor maternal and infant outcomes. Gestational weight gain, particularly in singleton pregnancies, has been well-linked with maternal and infant outcomes. The aim of the current meta-analysis was to evaluate the effects of gestational weight gain on maternal and fetal outcomes in women with twin pregnancies.
Methods: A systematic search was conducted using the PubMed, Scopus, and Google Scholar databases. Studies, either retrospective or prospective in design, evaluating the effects of gestational weight gain (defined using Institute of Medicine (IOM) guidelines) maternal and/or fetal/neonatal outcomes in women with twin pregnancies were included. Statistical analysis was performed using STATA software.
Results: Eleven studies were included in the meta-analysis. Mothers with inadequate weight gain had increased risk for gestational diabetes mellitus (OR 1.19; 95% CI: 1.01, 1.40) and decreased risk for gestational hypertension (OR 0.58; 95% CI: 0.49, 0.68) and cesarean section (OR 0.94; 95% CI: 0.93, 0.96). Neonates born to mothers with inadequate weight gain were susceptible to increased risk for preterm delivery (OR 1.17; 95% CI: 1.03, 1.34), very preterm delivery (gestational age <32 weeks) (OR 1.84; 95% CI: 1.36, 2.48), small for gestational age status (OR 1.41; 95% CI: 1.15, 1.72), low birth weight status (<2,500 g) (OR 1.27; 95% CI: 1.17, 1.38), and neonatal intensive care unit (NICU) admission (OR 1.16; 95% CI: 1.08, 1.24). The pooled findings indicate an increased risk for gestational hypertension (OR 1.82; 95% CI: 1.60, 2.06) and cesarean section (OR 1.07; 95% CI: 1.05, 1.08) among mothers with excessive weight gain. Neonates born to mothers with excessive weight gain were susceptible to increased risk for preterm delivery and very preterm delivery, but were associated with a decreased risk for low birth weight status and small for gestational age status.
Conclusions: Gestational weight gain in twin pregnancy, either lower or higher than IOM recommended guidelines, is associated with poor maternal and neonatal outcomes. Our findings call for incorporating counseling on optimal weight gain during pregnancy as part of routine antenatal visits.

研究背景：近年来双胎妊娠（twin pregnancies）的发生率呈上升趋势。此类妊娠与孕产妇及新生儿不良妊娠结局风险升高显著相关。目前，妊娠期体重增长（gestational weight gain）与单胎妊娠母婴结局的关联已得到充分阐明。本荟萃分析旨在评估双胎妊娠女性的妊娠期体重增长对母体及胎儿妊娠结局的影响。
研究方法：本研究通过PubMed、Scopus及Google Scholar三大数据库开展系统性文献检索。纳入所有以美国医学研究所（Institute of Medicine, IOM）指南定义妊娠期体重增长，评估双胎妊娠女性母体及/或胎儿/新生儿妊娠结局的研究，研究设计包括回顾性及前瞻性两种。统计分析采用STATA统计软件完成。
研究结果：本荟萃分析最终纳入11项符合标准的研究。与体重增长符合指南标准的孕产妇相比，体重增长不足者罹患妊娠期糖尿病（gestational diabetes mellitus）的风险升高（比值比OR=1.19；95%置信区间CI:1.01~1.40），而罹患妊娠期高血压及接受剖宫产的风险显著降低（妊娠期高血压：OR=0.58；95%CI:0.49~0.68；剖宫产：OR=0.94；95%CI:0.93~0.96）。体重增长不足的孕产妇所分娩的新生儿，早产、极早产（孕龄<32周）、小于胎龄儿、低出生体重儿（出生体重<2500g）及需入住新生儿重症监护病房（neonatal intensive care unit, NICU）的风险均显著升高，对应比值比及置信区间分别为：早产OR=1.17；95%CI:1.03~1.34，极早产OR=1.84；95%CI:1.36~2.48，小于胎龄儿OR=1.41；95%CI:1.15~1.72，低出生体重儿OR=1.27；95%CI:1.17~1.38，新生儿重症监护病房入住率OR=1.16；95%CI:1.08~1.24。合并分析结果显示，体重增长过量的孕产妇罹患妊娠期高血压（OR=1.82；95%CI:1.60~2.06）及接受剖宫产（OR=1.07；95%CI:1.05~1.08）的风险显著升高。体重增长过量的孕产妇所分娩的新生儿，早产及极早产风险升高，但低出生体重儿及小于胎龄儿的发生风险显著降低。
研究结论：双胎妊娠女性的妊娠期体重增长无论低于或高于美国医学研究所（IOM）推荐的指南标准，均与不良母婴妊娠结局显著相关。本研究结果提示，应将妊娠期最优体重增长咨询纳入常规产前随访的核心内容。