Doctors with Africa CUAMM, Padua, Italy.
Doctors with Africa CUAMM, Dar es Salaam, Tanzania.
BMC Pregnancy Childbirth. 2022 Jul 22;22(1):585. doi: 10.1186/s12884-022-04914-6.
Accurate gestational age (GA) determination allows correct management of high-risk, complicated or post-date pregnancies and prevention or anticipation of prematurity related complications. Ultrasound measurement in the first trimester is the gold standard for GA determination. In low- and middle-income countries elevated costs, lack of skills and poor maternal access to health service limit the availability of prenatal ultrasonography, making it necessary to use alternative methods. This study compared three methods of GA determination: Last Normal Menstrual Period recall (LNMP), New Ballard Score (NBS) and New Ballard Score corrected for Birth Weight (NBS + BW) with the locally available standard (Ultrasound measurement in the third trimester) in a low-resource setting (Tosamaganga Council Designated Hospital, Iringa, Tanzania).
All data were retrospectively collected from hospital charts. Comparisons were performed using Bland Altman method.
The analysis included 70 mother-newborn pairs. Median gestational age was 38 weeks (IQR 37-39) according to US. The mean difference between LNMP vs. US was 2.1 weeks (95% agreement limits - 3.5 to 7.7 weeks); NBS vs. US was 0.2 weeks (95% agreement limits - 3.7 to 4.1 weeks); NBS + BW vs. US was 1.2 weeks (95% agreement limits - 1.8 to 4.2 weeks).
In our setting, NBS + BW was the least biased method for GA determination as compared with the locally available standard. However, wide agreement bands suggested low accuracy for all three alternative methods. New evidence in the use of second/third trimester ultrasound suggests concentrating efforts and resources in further validating and implementing the use of late pregnancy biometry for gestational age dating in low and middle-income countries.
准确的孕周（GA）确定可实现对高危、复杂或过期妊娠的正确管理，并预防或预测与早产相关的并发症。在第一孕期进行超声测量是 GA 确定的金标准。在低收入和中等收入国家，由于成本高昂、技能缺乏以及产妇获得卫生服务的机会有限，限制了产前超声的应用，因此需要使用替代方法。本研究比较了三种 GA 确定方法：末次正常月经周期回忆法（LNMP）、新 Ballard 评分（NBS）和校正出生体重的新 Ballard 评分（NBS+BW）与在资源匮乏环境中（坦桑尼亚伊林加 Tosamaganga 理事会指定医院）本地可用的标准（第三孕期超声测量）。
所有数据均从医院病历中回顾性收集。采用 Bland-Altman 方法进行比较。
本分析共纳入 70 对母婴。根据 US 结果，中位 GA 为 38 周（IQR 37-39）。LNMP 与 US 之间的平均差值为 2.1 周（95%一致性界限为-3.5 至 7.7 周）；NBS 与 US 之间的差值为 0.2 周（95%一致性界限为-3.7 至 4.1 周）；NBS+BW 与 US 之间的差值为 1.2 周（95%一致性界限为-1.8 至 4.2 周）。
在我们的环境中，与本地可用的标准相比，NBS+BW 是 GA 确定中偏差最小的方法。然而，所有三种替代方法的一致性范围较宽，提示其准确性较低。在第二/三期超声使用方面的新证据表明，应集中精力和资源，进一步验证和实施中低收入国家妊娠晚期生物测量用于 GA 日期的方法。
