严重的碘缺乏影响生育和生殖结果。轻度至中度碘缺乏的潜在影响尚不清楚。这项研究的目的是检查碘摄入量是否与亚生育(即>12个月试图怀孕)有关。胎儿生长,轻度至中度碘缺乏人群的不良妊娠结局。
我们用了挪威母亲,父亲和孩子队列研究(MoBa)包括78,318例怀孕,包括碘摄入量和妊娠结局的数据。在怀孕中期使用广泛的食物频率问卷计算碘摄入量。此外,在2795例妊娠子样本中可获得尿碘浓度.通过多变量回归控制一系列混杂因素,对关联进行连续建模。
食物中碘摄入量中位数为121μg/天,尿碘中位数为69μg/L,确认轻度至中度碘缺乏。在非碘补充剂使用者中(n=49,187),低碘摄入量(<100-150μg/天)与先兆子痫的风险增加相关(aOR=1.14(95%CI1.08,1.22)100μg/天,p总体<0.001),妊娠第37周前早产(aOR=1.10(1.04,1.16)在75与100μg/天,p总体=0.003),并降低胎儿生长(-0.08SD(-0.10,-0.06)出生体重z评分在75与150μg/天,p总体<0.001),但不是早期早产或宫内死亡。在计划怀孕中(n=56,416),碘摄入量低于〜100μg/天与亚繁殖力患病率增加有关(aOR=1.05(1.01,1.09)在75μg/天与100μg/天,总体p=0.005)。长期使用碘补充剂(在怀孕前开始)与胎儿生长增加有关(出生体重z评分+0.05SD(0.03,0.07),p<0.001)和降低先兆子痫的风险(aOR0.85(0.74,0.98),p=0.022),但与其他不良妊娠结局无关。尿碘浓度与任何二分法结局无关,但与胎儿生长呈正相关(n=2795,p总体=0.017)。
这项研究表明,在这些轻度至中度缺碘妇女中,低碘摄入量与胎儿生长受限和先兆子痫患病率较高有关。结果还表明,低生育和早产的风险增加。在怀孕期间开始使用碘补充剂可能为时已晚。
Severe iodine deficiency impacts fertility and reproductive outcomes. The potential effects of mild-to-moderate iodine deficiency are not well known. The aim of this
study was to examine whether iodine intake was associated with subfecundity (i.e. > 12 months trying to get pregnant), foetal growth, and adverse pregnancy outcomes in a mild-to-moderately iodine-deficient population.
We used the Norwegian Mother, Father and Child Cohort
Study (MoBa) and included 78,318 pregnancies with data on iodine intake and pregnancy outcomes. Iodine intake was calculated using an extensive food frequency questionnaire in mid-pregnancy. In addition, urinary iodine concentration was available in a subsample of 2795 pregnancies. Associations were modelled continuously by multivariable regression controlling for a range of confounding factors.
The median iodine intake from food was 121 μg/day and the median urinary iodine was 69 μg/L, confirming mild-to-moderate iodine deficiency. In non-users of iodine supplements (n = 49,187), low iodine intake (< 100-150 μg/day) was associated with increased risk of preeclampsia (aOR = 1.14 (95% CI 1.08, 1.22) at 75 vs. 100 μg/day, p overall < 0.001), preterm delivery before gestational week 37 (aOR = 1.10 (1.04, 1.16) at 75 vs. 100 μg/day, p overall = 0.003), and reduced foetal growth (- 0.08 SD (- 0.10, - 0.06) difference in birth weight z-score at 75 vs. 150 μg/day, p overall < 0.001), but not with early preterm delivery or intrauterine death. In planned pregnancies (n = 56,416), having an iodine intake lower than ~ 100 μg/day was associated with increased prevalence of subfecundity (aOR = 1.05 (1.01, 1.09) at 75 μg/day vs. 100 μg/day, p overall = 0.005). Long-term iodine supplement use (initiated before pregnancy) was associated with increased foetal growth (+ 0.05 SD (0.03, 0.07) on birth weight z-score, p < 0.001) and reduced risk of preeclampsia (aOR 0.85 (0.74, 0.98), p = 0.022), but not with the other adverse pregnancy outcomes. Urinary iodine concentration was not associated with any of the dichotomous outcomes, but positively associated with foetal growth (n = 2795, p overall = 0.017).
This
study shows that a low iodine intake was associated with restricted foetal growth and a higher prevalence of preeclampsia in these mild-to-moderately iodine-deficient women. Results also indicated increased risk of subfecundity and preterm delivery. Initiating iodine supplement use in pregnancy may be too late.