The Impact of Maternal Metabolic Syndrome on Gross Placental Structure in Term Pregnancies: A Comparative Study

Background and objective The placenta is a key indicator of the intrauterine environment and directly affects fetal growth. Maternal metabolic syndrome (MetS), which is increasingly common during pregnancy, can impair placental development through chronic inflammation, insulin resistance, and vascular dysfunction. This study aimed to compare the gross morphology of the placenta and umbilical cord in pregnancies complicated by MetS with those in pregnancies without the condition, and to assess associated neonatal birthweight outcomes. Methods This cross-sectional comparative study included 60 term placentae, comprising 30 from MetS pregnancies and 30 from control pregnancies. Gross placental parameters assessed included placental weight, length, breadth, thickness, cotyledon number, and umbilical cord length and diameter. Neonatal outcomes assessed included birth weight and the placental to birth weight ratio. Statistical analysis was performed using the Student's t-test, with a p-value < 0.05 considered significant. Results Placentae from MetS pregnancies were significantly smaller and lighter than those from the control group (440 ± 52 g vs. 515 ± 48 g; p < 0.001), with significant reductions in placental length, breadth, and cotyledon number (p < 0.001). Umbilical cord length was also significantly shorter in the MetS group (38.5 ± 5.8 cm vs. 46.4 ± 6.1 cm; p < 0.001). Neonates born to MetS mothers had a lower birth weight (2.65 ± 0.34 kg vs. 3.05 ± 0.28 kg; p < 0.001) and a lower placenta-birth weight ratio (0.162 ± 0.02 vs. 0.171 ± 0.03; p = 0.045), indicating reduced placental efficiency. Conclusions Maternal MetS is associated with restricted placental development, reduced placental efficiency, and significant impairment of fetal growth. Routine gross placental morphometry, when paired with neonatal anthropometry, offers a simple, effective tool for identifying fetoplacental insufficiency in MetS pregnancies and underscores the importance of early metabolic risk assessment and improved fetal surveillance.