JAMA Netw Open

Low placental growth factor levels linked to increased risk of early preterm birth

November 20, 2024

A low placental growth factor (PlGF) level (<100 pg/mL) detected during routine gestational diabetes screening could effectively identify pregnant individuals at risk for early preterm birth, particularly in cases of iatrogenic delivery. Redirecting healthcare resources to this high-risk group may enhance maternal and perinatal outcomes.

This prospective cohort study was conducted at an urban tertiary care center from 2020 to 2023. It included unselected pregnant individuals with singleton pregnancies who received universal-access prenatal care from obstetricians, family physicians, or midwives. Participants underwent a PlGF test during routine gestational diabetes screening, typically conducted between 24 and 28 weeks of gestation.

Findings

• Among 9,037 pregnant individuals, 156 (1.7%) had early preterm births, with 52 being spontaneous and 104 iatrogenic. The area under the curve (AUC) for PlGF in predicting early preterm birth was 0.80 (95% CI, 0.75-0.85).
• Low PlGF levels were strongly linked to early preterm birth, showing a positive likelihood ratio of 79.4 and a specificity of 99.5%.
• Patients with PlGF levels below 100 pg/mL delivered significantly sooner, with over 50% giving birth within 50 days.
• Those with low PlGF accounted for more than 30% of stillbirths and over half of iatrogenic early preterm births. The AUC for iatrogenic early preterm birth was 0.90 (95% CI, 0.85-0.94).

Source:

Gladstone RA, et al. (2024, November 4). JAMA Network Open. Midpregnancy placental growth factor screening and early preterm birth. https://pubmed.ncbi.nlm.nih.gov/39541121/