The Ritchie Centre, Department of Obstetrics and Gynaecology, Monash University, Melbourne, Victoria, Australia.
Safer Care Victoria, Department of Health and Human Services, Victorian Government, Melbourne, Victoria, Australia.
BJOG. 2021 Jul;128(8):1304-1312. doi: 10.1111/1471-0528.16665. Epub 2021 Mar 1.
To quantify how the changing stillbirth risk profile of women is affecting the interpretation of the stillbirth rate.
A retrospective, population-based cohort study from 1983 to 2018.
Victoria, Australia.
A total of 2 419 923 births at ≥28 weeks of gestation.
Changes in maternal characteristics over time were assessed. A multivariable logistic regression model was developed for stillbirth, based on maternal characteristics in 1983-1987, and used to calculate individual predictive probabilities of stillbirth from the regression equation. The number of expected stillbirths per year as a result of the change in maternal demographics was then calculated, assuming no changes in care and in the associations between maternal characteristics and stillbirth over time.
Stillbirth.
Compared with 1983-1987, there were more women in older age groups giving birth, more nulliparous women, more indigenous women and women born in Oceania, Asia and Africa, more multiple pregnancies and more women with pre-existing diabetes in 2014-2018. Despite this, the rate of stillbirth fell from 5.42 per 1000 births in 1983 to 1.72 per 1000 births in 2018 (P < 0.001). Applying the multivariable logistic regression equation, derived from the 1983-87 data, to each year, had there been no changes in care or in the associations between maternal characteristics and stillbirth, the rate of stillbirth would have increased by 12%, from 4.94 per 1000 in 1983 to 5.54 per 1000 in 2018, as a result of the change in maternal characteristics.
Population rates of stillbirth are falling faster than is generally appreciated.
Population reductions in stillbirth have been underestimated as a result of changing maternal characteristics.
量化女性不断变化的死产风险状况如何影响死产率的解读。
1983 年至 2018 年的回顾性、基于人群的队列研究。
澳大利亚维多利亚州。
共有 2419923 名≥28 周妊娠的分娩。
评估随时间推移的产妇特征变化。根据 1983-1987 年的产妇特征，建立了死产的多变量逻辑回归模型，并使用回归方程计算了每年因产妇特征变化而导致的预期死产数量。假设护理和随时间推移产妇特征与死产之间的关联没有变化，则计算出每年由于产妇人口统计学变化而导致的预期死产数量。
死产。
与 1983-1987 年相比，2014-2018 年，分娩的产妇年龄更大，初产妇更多，土著产妇更多，出生于大洋洲、亚洲和非洲的产妇更多，多胎妊娠更多，患有既往糖尿病的产妇更多。尽管如此，死产率从 1983 年的每 1000 例活产 5.42 例下降到 2018 年的每 1000 例活产 1.72 例（P<0.001）。如果没有护理方面的变化，也没有产妇特征与死产之间关联的变化，应用从 1983-87 年数据中得出的多变量逻辑回归方程，每年的死产率将增加 12%，从 1983 年的每 1000 例活产 4.94 例增加到 2018 年的每 1000 例活产 5.54 例，这是由于产妇特征的变化。
人口死产率的下降速度超过了普遍的认识。
由于产妇特征的变化，死产的人口减少被低估了。
