MRC Centre for Causal Analyses in Translational Epidemiology, School of Social and Community Medicine, University of Bristol, Bristol, UK.
J Hypertens. 2011 Sep;29(9):1703-11. doi: 10.1097/HJH.0b013e328349eec6.
Hypertension during pregnancy is one of the diagnostic criteria for preeclampsia. We investigated the pattern of blood pressure (BP) change across pregnancy and associations of risk factors for preeclampsia with BP changes in normal pregnancy.
We examined repeat antenatal BP measurements (median 14 per woman) of 11,789 women from the Avon Longitudinal Study of Parents and Children cohort with a live-term birth and no evidence of preeclampsia or previous hypertension. Linear spline random effects models with knots at 18, 30 and 36 weeks gestation described changes in BP with gestational age.
On average, SBP and DBP decreased slowly until 18 weeks and rose from 18 weeks onwards, with increasing rate at 30 weeks and then again at 36 weeks. In obese women, BP was higher at 8 weeks and rose more slowly between 18 and 30 weeks and more rapidly between 30 and 36 weeks than in normal-weight women. Nulliparous women had higher BP at 8 weeks and faster increases in DBP from 30 weeks and SBP from 36 weeks onwards than multiparas. Women who smoked throughout pregnancy had lower BP at 8 weeks and throughout pregnancy; women who only smoked in the first trimester soon attained the same pattern of change as never smokers. In twin pregnancies, BP rose more rapidly from 30 weeks onwards than in singleton pregnancies.
Established preeclampsia risk factors are associated with higher BP in early pregnancy and faster BP increases later in gestation in normal pregnancy, suggesting a continuum of risk.
孕期高血压是子痫前期的诊断标准之一。我们研究了妊娠期间血压（BP）变化的模式，以及子痫前期的危险因素与正常妊娠中 BP 变化的关系。
我们对来自阿冯纵向研究父母和儿童队列的 11789 名足月分娩且无子痫前期或既往高血压证据的妇女进行了重复产前 BP 测量（中位数为每名妇女 14 次）。线性样条随机效应模型在 18、30 和 36 孕周有结，描述了 BP 随孕龄的变化。
平均而言，SBP 和 DBP 在 18 周前缓慢下降，从 18 周开始上升，30 周时上升速度加快，36 周时再次加快。在肥胖妇女中，BP 在 8 周时更高，在 18 至 30 周之间上升缓慢，在 30 至 36 周之间上升更快。初产妇在 8 周时 BP 更高，从 30 周开始 DBP 增加更快，从 36 周开始 SBP 增加更快。整个孕期吸烟的妇女在 8 周时 BP 较低，整个孕期的 BP 也较低；仅在孕早期吸烟的妇女很快就会出现与从不吸烟者相同的变化模式。在双胎妊娠中，BP 从 30 周开始上升得更快。
已确定的子痫前期危险因素与正常妊娠中早期妊娠的较高 BP 和妊娠后期较快的 BP 升高有关，这表明存在风险连续体。
