McLennan Amelia S, Gyamfi-Bannerman Cynthia, Ananth Cande V, Wright Jason D, Siddiq Zainab, D'Alton Mary E, Friedman Alexander M
Department of Obstetrics and Gynecology, College of Physicians and Surgeons, Columbia University, New York, NY.
Department of Obstetrics and Gynecology, College of Physicians and Surgeons, Columbia University, New York, NY; Department of Epidemiology, Joseph L. Mailman School of Public Health, Columbia University, New York, NY.
Am J Obstet Gynecol. 2017 Jul;217(1):80.e1-80.e8. doi: 10.1016/j.ajog.2017.03.002. Epub 2017 Mar 9.
There are limited data on how maternal age is related to twin pregnancy outcomes.
The purpose of this study was to assess the relationship between maternal age and risk for preterm birth, fetal death, and neonatal death in the setting of twin pregnancy.
This population-based study of US birth, fetal death, and period-linked birth-infant death files from 2007-2013 evaluated neonatal outcomes for twin pregnancies. Maternal age was categorized as 15-17, 18-24, 25-29, 30-34, 35-39, and ≥40 years of age. Twin live births and fetal death delivered at 20-42 weeks were included. Primary outcomes included preterm birth (<34 weeks and <37 weeks), fetal death, and neonatal death at <28 days of life. Analyses of preterm birth at <34 and <37 weeks were adjusted for demographic and medical factors, with maternal age modeled with the use of restricted spline transformations.
A total of 955,882 twin live births from 2007-2013 were included in the analysis. Preterm birth rates at <34 and <37 weeks gestation were highest for women 15-17 years of age, decreased across subsequent maternal age categories, nadired for women 35-39 years old, and then increased slightly for women ≥40 years old. Risk for fetal death generally decreased across maternal age categories. Risk for fetal death was 39.9 per 1000 live births for women 15-17 years old, 24.2 for women 18-24 years old, 17.8 for women 25-29 years old, 16.4 for women 30-34 years old, 17.2 for women 35-39 years old, and 15.8 for women ≥40 years old. Risk for neonatal death at <28 days was highest for neonates born to women 15-17 years old (10.0 per 1,000 live births), decreased to 7.3 for women 18-24 years old and 5.5 for women 25-29 years old and ranged from 4.3-4.6 for all subsequent maternal age categories. In adjusted models, risk for preterm birth at <34-<37 weeks gestation was not elevated for women in their mid-to-late 30s; however, risk was elevated for women <20 years old and increased progressively with age for women in their 40s.
Although twin pregnancy is associated with increased risk for most adverse perinatal outcomes, this analysis did not find advanced maternal age to be an additional risk factor for fetal death and infant death. Preterm birth risk was relatively low for women in their late 30s. Risks for adverse outcomes were higher among younger women; further research is indicated to improve outcomes for this demographic group. It may be reasonable to counsel women in their 30s that their age is not a major additional risk factor for adverse obstetric outcomes in the setting of twin pregnancy.
关于母亲年龄与双胎妊娠结局之间的关系，相关数据有限。
本研究旨在评估双胎妊娠情况下母亲年龄与早产、胎儿死亡及新生儿死亡风险之间的关系。
这项基于人群的研究利用了2007 - 2013年美国出生、胎儿死亡及与孕周相关的出生 - 婴儿死亡档案，对双胎妊娠的新生儿结局进行评估。母亲年龄分为15 - 17岁、18 - 24岁、25 - 29岁、30 - 34岁、35 - 39岁及≥40岁。纳入20 - 42周分娩的双胎活产及胎儿死亡情况。主要结局包括早产（<34周和<37周）、胎儿死亡及出生后<28天的新生儿死亡。对<34周和<37周的早产分析进行了人口统计学和医学因素调整，母亲年龄采用受限样条变换进行建模。
分析纳入了2007 - 2013年共955,882例双胎活产病例。妊娠<34周和<37周的早产率在15 - 17岁女性中最高，在随后的母亲年龄组中逐渐下降，在35 - 39岁女性中降至最低点，然后在≥40岁女性中略有上升。胎儿死亡风险总体上随母亲年龄组增加而降低。15 - 17岁女性的胎儿死亡风险为每1000例活产39.9例，18 - 24岁女性为24.2例，25 - 29岁女性为17.8例，30 - 34岁女性为16.4例，35 - 39岁女性为17.2例，≥40岁女性为15.8例。出生后<28天的新生儿死亡风险在15 - 17岁女性所生新生儿中最高（每1000例活产10.0例），18 - 24岁女性降至7.3例，25 - 29岁女性降至5.5例，在随后所有母亲年龄组中为4.3 - 4.6例。在调整模型中，妊娠<34 - <37周的早产风险在35岁及以上的中晚期女性中并未升高；然而，<20岁女性的风险升高，40多岁女性的风险随年龄逐渐增加。
尽管双胎妊娠与大多数不良围产期结局风险增加相关，但本分析未发现母亲年龄较大是胎儿死亡和婴儿死亡的额外风险因素。35岁及以上的晚期女性早产风险相对较低。年轻女性不良结局风险较高；需要进一步研究以改善该人群的结局。建议35岁左右的女性，在双胎妊娠情况下，她们的年龄并非不良产科结局的主要额外风险因素，这可能是合理的。
