Perinatal Services BC, Vancouver, BC.
CMAJ. 2013 May 14;185(8):E345-51. doi: 10.1503/cmaj.121372. Epub 2013 Apr 8.
After decades of decline, stillbirth rates have increased in several industrialized countries in recent years. We examined data from the province of British Columbia, Canada, in an attempt to explain this unexpected phenomenon.
We carried out a retrospective population-based cohort study of all births in British Columbia from 2000 to 2010. Outcomes of interest included overall stillbirth rates, birth weight-and gestational age-specific stillbirth rates, rates of spontaneous stillbirths (excluding pregnancy terminations that satisfied the definition of stillbirth [fetal death with a birth weight ≥ 500 g or gestational age at delivery ≥ 20 wk], hereafter referred to as "pregnancy terminations") and rates of congenital anomalies among live-born infants. We used logistic regression to adjust for changes in maternal age, parity, weight before pregnancy and multiple births.
Overall, stillbirth rates increased by 31% (95% confidence interval [CI] 13% to 50%), from 8.08 per 1000 total births in 2000 to 10.55 per 1000 in 2010. The rate of stillbirths with a birth weight of less than 500 g increased significantly (p(trend) = 0.03), whereas the rate of stillbirths with a birth weight of 1000 g or more decreased significantly (p(trend) = 0.009). The rate of spontaneous stillbirths decreased nonsignificantly by 16%, from 5.7 per 1000 total births in 2000 to 4.8 per 1000 in 2010. There was a significant decline of 30% (95% CI 6% to 47%) in the rate of spontaneous stillbirth with a birth weight of 1000 g or more between 2000 and 2010; adjustment for maternal factors did not appreciably change this temporal effect. The prevalence of congenital anomalies among live-born infants decreased significantly, from 5.21 per 100 live births during the first 3 years (2000-02) to 4.77 per 100 during the final 3 years (2008-10).
Increases in pregnancy terminations were responsible for the increases observed in stillbirth rates and were associated with declines in the prevalence of congenital anomalies among live-born infants.
在经历几十年的下降后，近年来一些工业化国家的死产率又出现上升。我们对加拿大不列颠哥伦比亚省的数据进行了研究，试图解释这一意外现象。
我们对不列颠哥伦比亚省 2000 年至 2010 年所有出生的情况进行了回顾性基于人群的队列研究。感兴趣的结局包括总死产率、出生体重和胎龄特定的死产率、自发性死产率（不包括符合死产定义的妊娠终止[出生体重≥500 g 或分娩时胎龄≥20 周]，以下简称“妊娠终止”）和活产儿先天性异常发生率。我们使用逻辑回归来调整产妇年龄、产次、妊娠前体重和多胎的变化。
总体而言，死产率上升了 31%（95%置信区间[CI]为 13%至 50%），从 2000 年每 1000 例总分娩中的 8.08 例增加到 2010 年的 10.55 例。出生体重<500 g 的死产率显著增加（趋势检验 p 值=0.03），而出生体重≥1000 g 的死产率显著下降（趋势检验 p 值=0.009）。自发性死产率无显著下降 16%，从 2000 年每 1000 例总分娩中的 5.7 例降至 2010 年的每 1000 例 4.8 例。2000 年至 2010 年，出生体重≥1000 g 的自发性死产率下降了 30%（95%CI为 6%至 47%）；调整产妇因素后，这一时间效应并未明显改变。活产儿先天性异常的发生率显著下降，从第 1 个 3 年（2000-2002 年）的每 100 例活产儿 5.21 例降至最后 3 年（2008-2010 年）的每 100 例 4.77 例。
妊娠终止的增加导致了死产率的上升，并与活产儿先天性异常的发生率下降有关。
