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Abstract
Objective: To evaluate the association between PW, F/P ratio, and gestational age with neonatal birthweight and perinatal outcomes in a mixed-risk obstetric population.
Methods: This analytical cross-sectional study was conducted over six months at KRL Hospital, Kahuta. A total of 120 pregnant women attending for antenatal care and/or delivery were enrolled after informed consent. Maternal demographics, parity, and gestational age were recorded. At delivery, neonatal birthweight and placental weight (after standard trimming) were measured, and the F/P ratio was calculated as birthweight (g)/PW (g). Placental weight was categorized as <10th, 10th–90th and >90th percentile, and F/P ratio as <5 or ≥5. Descriptive statistics were generated, group differences were assessed using the χ² test, and correlations between PW and birthweight were examined using Pearson’s correlation coefficient (SPSS v26).
Results: Placental weight showed a strong association with birthweight category: low PW (<10th percentile) was present in 45.3% of low-birthweight infants versus 10.2% of normal-birthweight infants (p < 0.001), whereas normal PW (10th–90th percentile) was more frequent in the normal-birthweight group (80.5% vs 52.7%, p = 0.002). High PW (>90th percentile) also differed between groups (2.0% vs 9.3%, p = 0.03). An F/P ratio <5 was observed in 48.5% of low-birthweight neonates compared with 12.3% of normal-birthweight neonates (p < 0.001); conversely, an F/P ratio ≥5 predominated among normal-birthweight infants (87.7% vs 51.5%, p = 0.001). PW correlated positively with birthweight (r = 0.68, p < 0.001), underscoring the contribution of placental size to fetal growth. Shorter gestation is clustered with low birthweight and adverse perinatal outcomes.
Conclusion: In this cohort, lower placental weight and an F/P ratio <5 were strongly associated with low birthweight and adverse neonatal outcomes, while shorter gestational age further amplified risk. Routine measurement of PW, calculation of the F/P ratio, and careful monitoring of gestational duration may provide simple, low-cost tools to identify fetuses at risk for growth restriction and unfavourable perinatal outcomes in similar resource-limited settings.
Keywords: Placental weight; Fetal-to-placental weight ratio; Birthweight; Fetal growth restriction; Small for gestational age; Perinatal outcomes; Gestational age; Pakistan
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