TABLE 1.
Description of study participants
| Characteristic | n | Mean ± sd (%) |
|---|---|---|
| Maternal age at study enrollment (yr) | 154 | 17.1 ± 1.1 |
| Gestational age when entering prenatal care (wk) | 133 | 10.9 ± 5.4 |
| Gynecologic age at conception (yr) | 151 | 4.8 ± 1.9 |
| Prepregnancy BMI (kg/m2) | 153 | 24.9 ± 5.7 |
| Dietary Fe intake (mg/d) | 148 | 17.4 ± 7.7 |
| SF at 26 ± 4 wk gestation (midgestation) (μg/L) | 104 | 21.6 ± 17.9 |
| sTfR at 26 ± 4 wk gestation (midgestation) (mg/L) | 104 | 5.3 ± 4.7 |
| Hemoglobin at delivery (g/dl) | 145 | 11.5 ± 1.3 |
| Erythropoietin at delivery (mIU/ml) | 143 | 34.6 ± 29.4 |
| Gestational age at delivery (wk) | 154 | 39.8 ± 1.3 |
| Race | ||
| African American | 101 | (66) |
| White | 52 | (34) |
| American Indian | 1 | (<1) |
| Ethnicity | ||
| Hispanic | 42 | (27) |
| Non-Hispanic | 112 | (73) |
| Parity at study enrollment | ||
| 0 | 123 | (80) |
| ≥1 | 31 | (20) |
| Inadequate intake of dietary Fea | 112 | (76) |
| Anemic at deliveryb | 27 | (19) |
The study was conducted with archived samples from 154 placentas that were collected from adolescents who participated in a larger longitudinal study of adolescent pregnancy. BMI, body mass index. aInadequate intake = total daily dietary iron intake <23 mg/d (the estimated average requirement for pregnant females age 14–18 yr) (45). bAnemia defined as hemoglobin < 10.2 g/dl in African American adolescents and <11.0 g/dl in all other patients.