The relationship of placental weight with birth weight

To assess the relationship between placental weight and birth weight, two hundred forty six pregnant mothers, who were otherwise healthy, were prospectively followed in a city hospital during antenatal period until delivery and immediate post-partum period. Height of mothers was measured initially and weight measured at each visit during the antenatal check-up. Placental weight and birth weight of babies were measured by one of the authors immediately after delivery by a weighing scale. Eighty one percent of the mothers were between the age group of 20-29 years. The BMI of 92% mothers was 18.5 and above. Most of the mothers came both with primigravida (42%) or second gravida (33%) and in 25% cases 3rd or onwards. In 49% cases the placental weight was between 401-500 gm, in 30% cases >500 gm and in 21% cases 400 gm or less. There was delivery of appropriate-birth-weight babies in 85% cases and low-birth-weight babies in 15% cases. It was observed that a very strong correlation existed between placental weight and birth weight (r = 0.391, p<0.001). Even this correlation was stronger in small for gestational age babies. However, there was no correlation between placental weight and APGAR score at one minute. It is concluded that increment of birth weight occurs with increase of placental weight. If placental weight can be measured by ultrasonography in second or early third trimester of pregnancy birth weight is possible to be assessed and appropriate measure can be taken to increase the birth weight.