Table 1

Selected Characteristics of 23,420 Mother Placenta Pairs in the Collaborative Perinatal Project.

Maternal Socio-Demographic Characteristics

Age (years)
24.5 ± 5.9
Education (years)

     ≥ 12
11,087 (47.4)
     < 12
12,333 (52.7)
Race

     White
12,198 (52.1)
     Black
11,222 (47.9)
Annual Family Income

     ≥ $5,000
6,907 (29.5)
     < $5,000
16,513 (70.5)
Smoking Intensity
22.8 ± 4.3
     Non-Smoker
12, 350 (52.7)
     Light Smoker (< 1 pack/day)
7, 084 (30.3)
     Heavy Smoker (≥ 1 pack/day)
3, 986 (17.0)
Pre-pregnancy BMI (kg/m2)
22.8 ± 4.3
Pregnancy weight gain (kg)
9.7 ± 5.0


Maternal Obstetric Characteristics

     Anemia
5,024 (21.5)
     Gestational Diabetes
360 (1.6)
     Hypertensive disease
543 (2.3)
     Parity

          Nulliparous
6,687 (28.6)
          Parous
16,733 (71.5)


Placental Characteristics

Placental Weight (grams)
438 ± 92
Placental thickness (mm)
21.9 ± 4.8
Chorionic plate area (cm2)
247.5 ± 51.3

All results presented as n (%) or mean ± SD

Equivalent to approximately $30,000 in 2005.

Baptiste-Roberts et al. BMC Pregnancy and Childbirth 2008 8:44   doi:10.1186/1471-2393-8-44