Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
Office of the Director, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
Nutrients. 2019 Mar 1;11(3):534. doi: 10.3390/nu11030534.
Iodine deficiency in pregnancy is a common problem in the United States and parts of Europe, but whether iodine deficiency is associated with increased pregnancy loss has not been well studied. The LIFE study provided an excellent opportunity to examine the relationship between iodine status and pregnancy loss because women were monitored prospectively to ensure excellent ascertainment of conceptions. The LIFE study, a population-based prospective cohort study, monitored 501 women who had discontinued contraception within two months to become pregnant; 329 became pregnant, had urinary iodine concentrations measured on samples collected at enrollment, and were followed up to determine pregnancy outcomes. Of the 329, 196 had live births (59.5%), 92 (28.0%) had losses, and 41 (12.5%) withdrew or were lost to follow up. Urinary iodine concentrations were in the deficiency range in 59.6% of the participants. The risk of loss, however, was not elevated in the mildly deficient group (hazard ratio 0.69, 95% confidence interval 0.34, 1.38), the moderately deficient group (hazard ratio 0.81, 95% confidence interval 0.43, 1.51), or the severely deficient group (hazard ratio 0.69, 95% confidence interval 0.32, 1.50). Iodine deficiency, even when moderate to severe, was not associated with increased rates of pregnancy loss. This study provides some reassurance that iodine deficiency at levels seen in many developed countries does not increase the risk of pregnancy loss.
妊娠碘缺乏在美国和欧洲部分地区是一个常见问题，但碘缺乏是否与妊娠丢失增加有关尚未得到很好的研究。LIFE 研究为研究碘状态与妊娠丢失之间的关系提供了极好的机会，因为对妇女进行了前瞻性监测，以确保对妊娠的准确确定。LIFE 研究是一项基于人群的前瞻性队列研究，监测了 501 名在两个月内停止避孕以怀孕的女性；其中 329 名怀孕，在入组时采集的尿液样本中测量了碘浓度，并进行了随访以确定妊娠结局。在这 329 名女性中，有 196 人（59.5%）活产，92 人（28.0%）流产，41 人（12.5%）退出或失访。然而，在轻度缺乏组（风险比 0.69，95%置信区间 0.34，1.38）、中度缺乏组（风险比 0.81，95%置信区间 0.43，1.51）或重度缺乏组（风险比 0.69，95%置信区间 0.32，1.50），流产风险并未升高。即使是中度到重度的碘缺乏也与妊娠丢失率增加无关。这项研究提供了一些保证，即在许多发达国家中看到的碘缺乏水平不会增加妊娠丢失的风险。
