Department of Obstetrics and Gynecology, Catharina Hospital, Eindhoven.
Clin Endocrinol (Oxf). 2010 Jun;72(6):820-4. doi: 10.1111/j.1365-2265.2009.03729.x. Epub 2009 Oct 15.
To study the relationship between suboptimal maternal thyroid function during gestation and breech presentation at term.
Prospective follow-up study during three trimesters of gestation.
A total of 1058 Dutch Caucasian healthy pregnant women were prospectively followed from 12 weeks gestation until term (>or=37 weeks) delivery.
Maternal thyroid parameters [TSH, free T4 (FT4) and auto-antibodies to thyroid peroxidase] were assessed at 12, 24 and 36 weeks gestation as well as foetal presentation at term.
At term, 58 women (5.5%) presented in breech. Compared with women with foetuses in the cephalic position, those women who presented in breech at term had significantly higher TSH concentrations, but only at 36 weeks gestation (P = 0.007). No between group differences were obtained for FT4 level at any assessment. The prevalence of breech presentation in the subgroup of women with TSH >or= 2.5 mIU/l (90th percentile) at 36 weeks gestation was 11%, compared with 4.8% in the women with TSH < 2.50 mIU/l (P = 0.006). Women with TSH below the 5th percentile had no breech presentations. Breech position was significantly and independently related to high maternal TSH concentration (>or=2.5 mIU/l) at 36 weeks gestation (O.R.: 2.23, 95% CI: 1.14-4.39), but not at 12 and 24 weeks gestation.
Women with TSH levels above 2.5 mIU/l during end gestation are at risk for breech presentation, and as such for obstetric complications.
研究妊娠期间亚临床甲状腺功能不全与足月臀位的关系。
妊娠三个时期的前瞻性随访研究。
1058 名荷兰白种健康孕妇，从妊娠 12 周开始一直前瞻性随访至足月（≥37 周）分娩。
分别于妊娠 12、24 和 36 周检测母体甲状腺参数[促甲状腺激素（TSH）、游离甲状腺素（FT4）和甲状腺过氧化物酶自身抗体]，并记录足月时的胎儿先露位置。
在足月时，58 名（5.5%）孕妇为臀位。与头位孕妇相比，足月臀位孕妇的 TSH 浓度明显更高，仅在妊娠 36 周时差异有统计学意义（P = 0.007）。在任何评估时，FT4 水平在两组间均无差异。在妊娠 36 周 TSH ＞2.5 mIU/l（90 百分位）的孕妇亚组中，臀位的发生率为 11%，而 TSH ＜2.50 mIU/l 的孕妇中发生率为 4.8%（P = 0.006）。TSH 在第 5 百分位以下的孕妇无臀位。36 周时，高母体 TSH 浓度（＞2.5 mIU/l）与臀位显著相关（优势比：2.23，95%可信区间：1.14-4.39），但在 12 周和 24 周时与臀位无相关性。
妊娠末期 TSH 水平＞2.5 mIU/l 的孕妇有臀位的风险，从而有产科并发症的风险。
