ESPE Abstracts

Background: Epidemiological studies have shown associations between placental weight (PW) and perinatal and postnatal linear growth and weight gain.

Objectives: To report trimmed placental weight (PWT) and evaluate their association with birth weight (BWT), and gestational age (GA) in a large cohort of mother/ baby pairs in Qatar. (n= 80722).

Methods: Retrospective data analysis of 80722 births, in Hamad Medical Corporation Hospitals for 4 years (2016 - 2019) in Qatar. The data was retrieved from routinely collected hospital data. The inclusion criterion for this analysis was term singleton live births, 37+0 to 42+6 weeks gestation. We classified newborn sizes based on gestational age and birthweight, into SGA (<10th percentile), AGA (between 10th and 90th percentiles) and LGA (> 90th percentile) using intergrowth-21st standards. In addition, we also explored placenta to birth weight ratios and estimated newborn proportions (%) for each gestational age group (sex not included).

Results: Overall, the mean birth and placenta weights were 3282 ± 439 and 661 ± 104 grams respectively. For each newborn size, these were AGA (3223 ± 313), SGA (2512 ± 247), and LGA (3938 ± 273) while placental weights were AGA (651 ± 88), SGA (550 ± 103) and LGA (766 ± 106) grams. Birth weights and placenta weights were directly proportional to the size of the baby. This relationship was converse in the placenta weight to birth weight ratio where the SGA babies had higher mean PW/BWT ratios; AGA (0.203), SGA (0.219) and LGA (0.195) (table 1). The proportion of SGA babies who had PWT/BWT ratios above 90th percentile for each respective GA group ranged from 28% to 43%.

Conclusion: Placental measurements are powerful independent predictors of birth weight. An increased PWT/BWT ratio in SGA babies indicates that nutrient transfer, per gram placenta, is reduced, supporting rodents’ studies.