Table 1.
Characteristics, biomarkers, and human milk concentrations of participants followed in the cohort in Rio de Janeiro, Brazil.
| Characteristic | Valuesa |
|---|---|
| Maternal age (n = 101) | 26 (22; 31) |
| Education (years) (n = 100) | 12 (9; 12) |
| Parity (n = 94) | |
| Primiparous | 51 (54.3) |
| Multiparous | 43 (45.7) |
| Marital status (n = 101) | |
| With a partner | 84 (83.2) |
| Without a partner | 17 (16.8) |
| Pre-pregnancy BMI (kg/m2) (n = 94) | |
| Underweight (<18.5) | 3 (3.2) |
| Normal weight (18.5–24.9) | 49 (52.1) |
| Overweight (25.0–29.9) | 30 (31.9) |
| Obesity (≥30.0) | 12 (12.8) |
| B-vitamin supplement intake during pregnancy (n = 101)b | |
| Yes | 89 (88.1) |
| No | 12 (11.9) |
| Multivitamin supplement intake during postpartum (n = 101) | |
| Yes | 3 (3.0) |
| No | 98 (97.0) |
| Maternal mental health at 3rd trimester of pregnancy | |
| Edinburgh Postnatal Depression Scale scores (n = 101) | 9 (6;12) |
| Edinburgh Postnatal Depression Scale categories (n = 101) | |
| ≥11 | 36 (35.6) |
| <11 | 65 (64.4) |
| State-Trait Anxiety Inventory scores (n = 101) | 37 (33; 42) |
| State-Trait Anxiety Inventory categories (n = 101) | |
| ≥40 | 40 (39.6) |
| <40 | 61 (60.4) |
| Serum biomarkers at 3rd trimester of pregnancy | |
| B-12 (pmol/L) (=92) | 172 (142; 220) |
| Homocysteine (μmol/L) (n = 91) | 5 (4; 5) |
| Folate (ng/Ml) (n = 92) | 10 (8; 14) |
| Serum biomarkers at 2–8 d postpartum | |
| B-12 (pmol/L) (n = 33) | 211 (147; 287) |
| B-12 deficient status (<148 pmol/L) (n = 33) | 9 (27.3) |
| Homocysteine (μmol/L) (n = 33) | 7 (6; 9) |
| Hyperhomocysteinemia (>15 μmol/L) (n = 33) | 0 (0) |
| Serum biomarkers at 28–50 d postpartum | |
| B-12 (pmol/L) (n = 78) | 310 (249; 391) |
| B-12 deficient status (<148 pmol/L) (n = 78) | 3 (3.9) |
| Homocysteine (μmol/L) (n = 78) | 7 (6; 8) |
| Hyperhomocysteinemia (>15 μmol/L) (n = 78) | 0 (0) |
| Serum biomarkers at 88–119 d postpartum | |
| B-12 (pmol/L) (n = 51) | 283 (217; 374) |
| B-12 deficient status (<148 pmol/L) (n = 51) | 0 (0) |
| Homocysteine (μmol/L) (n = 51) | 6 (6; 8) |
| Hyperhomocysteinemia (>15 μmol/L) (n = 51) | 0 (0) |
| B-12 human milk concentrations at various time points | |
| At 2–8 d postpartum (n = 47) | 270 (199; 407) |
| Low concentration (<310 pmol/L) at 2–8 d postpartum (n = 47) | 25 (53.2) |
| At 28-50 d postpartum (n = 70) | 239 (184; 345) |
| Low concentration (<310 pmol/L) at 28–50 d postpartum (n = 70) |
50 (71.4) |
| At 88-119 d postpartum (n = 38) | 245 (155; 317) |
| Low concentration (<310 pmol/L) at 88-119 d postpartum (n = 38) |
27 (71.1) |
| Breastfeeding status c | |
| Exclusive at 2–8 d postpartum (n = 47) | 42 (89.4) |
| Exclusive or predominant at 28–50 d postpartum (n = 70) | 53 (75.7) |
| Exclusive or predominant at 88–119 d postpartum (n = 38) | 26 (68.4) |
a
Values are medians (interquartile range) or the number of participants (%).
b
Including folic acid supplement intake.
c
Exclusive breastfeeding is defined as no other food or drink except human milk. Predominant breastfeeding is defined as human milk as an infant's primary source of nourishment; however, the infant may also have received liquids (including water or water-based drinks and fruit juice), ritual fluids, and medicines (42).