Browsing by Author "Beck, Celeste"

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    High early pregnancy body mass index is associated with alterations in first- and second-trimester angiogenic biomarkers
    (Elsevier, 2022) Beck, Celeste; Allshouse, Amanda; Silver, Robert M.; Grobman, William A.; Simhan, Hyagriv; Haas, David; Reddy, Uma M.; Blue, Nathan R.; Obstetrics and Gynecology, School of Medicine
    Background: Obesity is associated with various placenta-mediated adverse pregnancy outcomes, including preeclampsia, preterm birth, and stillbirth. Mechanisms linking obesity with placental dysfunction are not completely understood. Objective: This study aimed to examine the relationship between early pregnancy body mass index and placental angiogenic biomarkers soluble fms-like tyrosine kinase-1, placental growth factor, and the soluble fms-like tyrosine kinase-1-to-placental growth factor ratio. Study design: We conducted secondary analyses of an existing substudy within a multisite, prospective observational cohort study of nulliparous pregnant women in the United States. First- and second-trimester maternal blood samples, first-trimester body mass index, and demographic, lifestyle, and pregnancy outcomes data were collected. Soluble fms-like tyrosine kinase-1 and placental growth factor concentrations were measured at 6 to 13 and 16 to 22 weeks of gestation for women (cases) who experienced one of several adverse pregnancy outcomes (delivery at <37 weeks of gestation, preeclampsia or eclampsia, birthweight for gestational age <5th percentile, or stillbirth) and for those who had none of those outcomes (controls). We used multivariable mixed-effects linear regression models to estimate the association of body mass index with angiogenic biomarkers at both time points. We evaluated mean change between first- and second-trimester biomarker concentrations using multivariable linear regression models. Lastly, we used logistic regression models to estimate the risk of a high second-trimester soluble fms-like tyrosine kinase-1-to-placental growth factor ratio, using clinically established cutoffs for risk prediction. Results: Angiogenic biomarker and early pregnancy body mass index data were available for 2363 women (1467 with adverse pregnancy outcomes and 896 controls). High early pregnancy body mass index was associated with consistently lower soluble fms-like tyrosine kinase-1 concentrations across the first and second trimesters of pregnancy. We found lower first-trimester placental growth factor concentrations in the group with class II or III obesity (P<.001) and lower second-trimester placental growth factor concentrations among groups who were overweight, with class I obesity, and class II or III obesity (P<.001). For every unit increase in early pregnancy body mass index, there was a -4.4 pg/mL (95% confidence interval, -3.6 to -5.2) smaller mean increase in placental growth factor concentrations between the first and second trimesters of pregnancy. These differences resulted in significantly lower mean first-trimester soluble fms-like tyrosine kinase-1-to-placental growth factor ratios among groups who were overweight, with class I obesity, and class II or III obesity (P<.05) and in a significantly higher second-trimester soluble fms-like tyrosine kinase-1-to-placental growth factor ratio among the group with class II or III obesity (P<.001), compared with the group with normal body mass index. Each unit of increase in body mass index was associated with a 0.5 (95% confidence interval, 0.3-0.7) greater mean increase in the soluble fms-like tyrosine kinase-1-to-placental growth factor ratio between the first and second trimesters of pregnancy. In stratified analyses, associations between body mass index and angiogenic biomarkers soluble fms-like tyrosine kinase-1 and placental growth factor were similar in nonadverse pregnancy outcome and adverse pregnancy outcome subgroups, whereas associations between body mass index and the soluble fms-like tyrosine kinase-1-to-placental growth factor ratio were attenuated in the subgroups. Participants in the group with class II or III obesity were 3.13 (95% confidence interval, 1.15-8.49) times more likely than participants with normal weight to have a second-trimester ratio of ≥38 in univariate analysis. Conclusion: High early pregnancy body mass index was associated with lower soluble fms-like tyrosine kinase-1 and placental growth factor concentrations across early pregnancy. Maternal body mass was inversely associated with first-trimester soluble fms-like tyrosine kinase-1-to-placental growth factor ratios and positively associated with second-trimester soluble fms-like tyrosine kinase-1-to-placental growth factor ratios, driven by a diminished rise in placental growth factor between the first and second trimesters of pregnancy. Women with class II or III obesity have an increased risk of a high second-trimester soluble fms-like tyrosine kinase-1-to-placental growth factor ratio associated with placental dysfunction.
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    Maternal vitamin D status, fetal growth patterns, and adverse pregnancy outcomes in a multisite prospective pregnancy cohort
    (Elsevier, 2025) Beck, Celeste; Blue, Nathan R.; Silver, Robert M.; Na, Muzi; Grobman, William A.; Steller, Jonathan; Parry, Samuel; Scifres, Christina; Gernand, Alison D.; Obstetrics and Gynecology, School of Medicine
    Background: Few studies have examined maternal vitamin D status and fetal growth patterns across gestation. Furthermore, time points in pregnancy at which maternal vitamin D status is most critical for optimal fetal growth and pregnancy outcomes are uncertain. Objectives: Our objective was to examine whether first and second trimester maternal vitamin D status are associated with fetal growth patterns and pregnancy outcomes. Methods: We conducted a secondary analysis using data and samples from a multisite prospective cohort study of nulliparous pregnant females in the United States. We measured serum 25-hydroxyvitamin D (25(OH)D) for 351 participants at 6-13 and 16-21 weeks of gestation. Fetal growth was measured by ultrasound at 16-21 and 22-29 weeks of gestation, and neonatal anthropometric measures at birth. We constructed fetal growth curves using length, weight, and head circumference z-scores, and calculated risk of preterm birth (<37 wk) and small for gestational age (SGA). We examined outcomes across 25(OH)D concentrations assessed continuously, using Institute of Medicine (IOM) cutoffs (<50 compared with ≥50 nmol/L), and using exploratory cutoffs (<40, 40-59.9, 60-79.9, ≥80 nmol/L). Results: Vitamin D insufficiency (25(OH)D <50 nmol/L) was prevalent in 20% of participants in the first trimester. Each 10 nmol/L increase in first trimester 25(OH)D was associated with a 0.05 [95% confidence interval (CI): 0.01, 0.10] increase in length-for-age z-score but was not associated with weight or head circumference. There were no differences in risk of preterm birth or SGA using IOM cutoffs; participants with first trimester 25(OH)D <40 compared with ≥80 nmol/L had 4.35 (95% CI: 1.14, 16.55) times risk of preterm birth. Second trimester 25(OH)D was not associated with fetal growth patterns or with pregnancy outcomes. Conclusions: First trimester 25(OH)D is positively associated with linear growth. Low first trimester 25(OH)D (<40 nmol/L) is associated with a higher risk of preterm birth. Second trimester 25(OH)D is not associated with fetal growth or pregnancy outcomes assessed.