Harris Birthright Research Centre of Fetal Medicine, King's College Hospital, Denmark Hill, London SE5 9RS, UK.
Hum Reprod. 2011 Jul;26(7):1659-64. doi: 10.1093/humrep/der117. Epub 2011 Apr 12.
Pregnancies conceived by IVF are at increased risk of pre-eclampsia (PE). This study examines the potential mechanism for such association by examining the effect of method of conception on placentation as assessed by uterine artery Doppler at 11-13 weeks' gestation.
This prospective screening study at 11(+0)-13(+6) weeks for PE in singleton pregnancies used a combination of maternal history and uterine artery pulsatility index (PI). Regression analysis was performed to examine the association between the method of conception and both uterine artery PI and development of PE, after adjustment for maternal characteristics and obstetric history.
In the study population of 27 461 pregnancies, conception was spontaneous in 26 538 (96.6%), by IVF in 426 (1.6%) and by use of ovulation induction (OI) drugs in 497 (1.8%) pregnancies. Conception by IVF was associated with an increase in risk for early-PE, requiring delivery before 34 weeks [odds ratio 3.94, 95% confidence interval (CI) 1.51-10.27] but not for late-PE. In the OI group, the risk of early- and late-PE was not increased. In addition to IVF, other significant contributors to the prediction of early-PE were maternal weight, height, African and South Asian racial origin, previous and family history of PE and history of chronic hypertension. Significant contributions in explaining log(10) uterine artery PI were provided from maternal characteristics but not from the method of conception. The median uterine artery PI multiple of the median (MoM) in the IVF group (1.02 MoM) and in the OI group (1.03 MoM) were not significantly different from that of the spontaneous conception group (1.01 MoM; P= 0.870 and P= 0.296, respectively).
Conception by IVF substantially increases the risk for early-PE, through a mechanism unrelated to clinically measurable impairment in placental perfusion.
体外受精（IVF）受孕的妊娠发生子痫前期（PE）的风险增加。本研究通过在 11-13 周妊娠时使用子宫动脉多普勒评估胎盘形成情况，检查受孕方式对胎盘形成的影响，以探讨这种关联的潜在机制。
这项在 11（+0）-13（+6）周的单胎妊娠子痫前期的前瞻性筛查研究，使用了母体病史和子宫动脉搏动指数（PI）的组合。进行回归分析，以检查受孕方式与子宫动脉 PI 以及 PE 发生之间的关系，调整母体特征和产科史后进行分析。
在 27461 例妊娠的研究人群中，26538 例（96.6%）为自然受孕，426 例（1.6%）为 IVF 受孕，497 例（1.8%）为使用促排卵药物受孕。IVF 受孕与早期 PE 风险增加相关，需要在 34 周前分娩[比值比 3.94，95%置信区间（CI）1.51-10.27]，但与晚期 PE 无关。在 OI 组中，早期和晚期 PE 的风险并未增加。除 IVF 外，预测早期 PE 的其他重要因素包括母亲体重、身高、非洲和南亚种族、PE 的既往和家族史以及慢性高血压病史。从母亲特征而不是受孕方式可以解释对数（10）子宫动脉 PI 的显著差异。IVF 组（1.02 MoM）和 OI 组（1.03 MoM）的中位数子宫动脉 PI 倍数中位数（MoM）与自然受孕组（1.01 MoM）无显著差异（P=0.870 和 P=0.296）。
IVF 受孕会显著增加早期 PE 的风险，其机制与临床上可测量的胎盘灌注受损无关。
