Department of Obstetrics and Gynaecology, St George's University of London, St George's Hospital, London SW17 0RE, UK.
Hum Reprod. 2010 Aug;25(8):1895-9. doi: 10.1093/humrep/deq132. Epub 2010 Jun 2.
Our objective was to determine what effect maternal BMI has on fetal growth rate in the early first trimester.
This was a prospective observational study of singleton pregnancies with certain dates, initially presenting for a transvaginal scan (TVS) before 12 weeks of gestation. Maternal characteristics (BMI, ethnicity, maternal age, obstetric history, abdominal pain and vaginal bleeding) were recorded. Fetal crown-rump length (CRL) was measured at the initial scan, and at subsequent ultrasound assessments. In order to assess the fetal growth rates, women with at least two CRL measurements were included in the analysis. A mixed-linear effects model analysis was performed to determine whether BMI influences the rate of change in CRL.
A total of 264 pregnancies were analysed. The median BMI was 23.55 (range 16-45), median age was 32 (17-44) and the proportion of white, black and Asian women was 61.0, 15.5 and 5.3%, respectively. Mean gestational age (GA) at first TVS was 56 (range 33-84) days. Studying CRL as a function of GA with a mixed-linear effects model showed that this relationship was neither significantly influenced by BMI when modelling BMI as a continuous variable (P = 0.7529), nor when modelling it as a categorical variable using the WHO criteria (P = 0.8904).
Dating by CRL influences subsequent growth assessment and previous studies have suggested that first trimester fetal growth rates may be influenced by ethnicity and age. Our data however suggest that maternal BMI does not significantly influence early fetal growth.
我们的目的是确定母体 BMI 对早孕早期胎儿生长速度的影响。
这是一项对单胎妊娠的前瞻性观察性研究，这些妊娠具有特定的日期，最初在妊娠 12 周之前进行阴道超声（TVS）检查。记录了母体特征（BMI、种族、母亲年龄、产科史、腹痛和阴道出血）。在初始扫描时测量胎儿头臀长（CRL），并在随后的超声评估中测量。为了评估胎儿生长速度，将至少有两次 CRL 测量值的女性纳入分析。采用混合线性效应模型分析来确定 BMI 是否影响 CRL 的变化率。
共分析了 264 例妊娠。BMI 的中位数为 23.55（范围 16-45），中位数年龄为 32（17-44），白人、黑人、亚洲女性的比例分别为 61.0%、15.5%和 5.3%。首次 TVS 的平均孕龄（GA）为 56（范围 33-84）天。使用混合线性效应模型研究 CRL 与 GA 的关系表明，当将 BMI 建模为连续变量时（P=0.7529），或者当使用世界卫生组织（WHO）标准将其建模为分类变量时（P=0.8904），这种关系都不受 BMI 的显著影响。
CRL 确定的孕龄会影响后续的生长评估，先前的研究表明，早孕胎儿生长速度可能受种族和年龄的影响。然而，我们的数据表明，母体 BMI 并不显著影响早期胎儿生长。
