TABLE 4.
Change in human milk MN concentrations according to decrease in human milk volume between 2 and 5 mo postpartum (n = 193)1
| Median (25th, 75th percentiles) human milk concentration | Mean change (95% CI) in human milk concentration between 2 and 5 mo postpartum | Mean difference in change (95% CI) in human milk concentration between those who decreased their volume by >100 mL between 2 and 5 mo and those who did not2 | |||
|---|---|---|---|---|---|
| 2 mo postpartum (n = 193) | 5 mo postpartum (n = 193) | Participants who decreased their human milk volume by >100 mL (n = 62) | Participants who did not decrease their human milk volume by at least 100 mL (n = 131) | ||
| Sodium, mg/L | 123 (101, 173) | 101 (83, 122) | −21 (−83, 41) | −14 (−54, 26) | 7 (−65, 78) |
| Magnesium, mg/L | 29 (25, 32) | 28 (24, 32) | −0.2 (−1.9, 1.5) | −0.9 (−1.7, −0.2) | −0.7 (−2.3, 0.9) |
| Phosphorous, mg/L | 138 (125, 155) | 127 (115, 142) | −7 (−14, −1) | −13 (−18, −9) | −6 (−14, 2) |
| Potassium, mg/L | 450 (417, 485) | 420 (384, 462) | −9 (−25, 7) | −34 (−44, −24) | −25 (−43, −7) |
| Calcium, mg/L | 267 (247, 288) | 239 (220, 267) | −21 (−29, −13) | −29 (−33, −24) | −8 (−16, 1) |
| Iron, mg/L | 0.26 (0.20, 0.33) | 0.17 (0.13, 0.24) | −0.10 (−0.21, 0) | −0.13 (−0.17, −0.09) | −0.03 (0.12, 0.06) |
| Copper, mg/L | 0.30 (0.25, 0.35) | 0.23 (0.18, 0.27) | −0.06 (−0.08, −0.03) | −0.08 (−0.09, −0.06) | −0.02 (−0.05, 0.005) |
| Zinc, mg/L | 1.3 (0.9, 1.8) | 0.8 (0.6, 1.1) | −0.50 (−0.62, −0.39) | −0.51 (−0.59, −0.42) | −0.01 (−0.15, 0.14) |
| Selenium, μg/L | 13.9 (12.3, 16.6) | 12.2 (10.6, 14.7) | −0.75 (−4.1, 2.6) | −2.0 (−2.8, −1.1) | −1.2 (−3.8, 1.4) |
| Retinol, μg/L | 644 (472, 857) | 386 (279, 516) | −249 (−353, −145) | −333 (−404, −261) | −84 (−209, 42) |
| Retinol,3 μg/g milk fat | 12.1 (9.5, 16.9) | 9.3 (6.8, 12.6) | −3.6 (−5.6, −1.3) | −3.6 (−4.7, −2.4) | −0.1 (−2.3, 2.1) |
| β-Carotene, μg/L | 30.1 (19.5, 44.4) | 12.2 (7.6, 19.1) | −19 (−31, −8) | −24 (−28, −19) | −4 (−14, 5) |
| α-Carotene, μg/L | 12.6 (8.2, 16.9) | 6.2 (4.2, 8.4) | −8.4 (−14.1, −2.5) | −8.5 (−9.9, −7.0) | −0.2 (−4.7, 4.3) |
| β-Cryptoxanthin, μg/L | 38 (23, 59) | 12 (7, 22) | −28.8 (−39.6, −18.1) | −38.3 (−46.3, −30.3) | −9.5 (−23.2, 4.2) |
| α-Tocopherol,3 mg/L | 5.9 (4.4, 7.6) | 4.0 (2.9, 5.6) | −1.5 (−2.3, −0.6) | −2.2 (−2.8, −1.6) | −0.7 (−1.7, 0.3) |
| α-Tocopherol,3 mg/g milk fat | 0.11 (0.09, 0.14) | 0.10 (0.07, 0.13) | −0.02 (−0.03, 0) | −0.01 (−0.02, −0.01) | 0.00 (−0.02, 0.02) |
| γ-Tocopherol, mg/L | 0.51 (0.34, 0.74) | 0.34 (0.24, 0.51) | −0.08 (−0.19, 0.04) | −0.19 (−0.26, −0.13) | −0.11 (−0.24, 0.01) |
| γ-Tocopherol,3 mg/g milk fat | 0.01 (0.01, 0.01) | 0.01 (0.01, 0.01) | 0 (0, 0) | 0 (0, 0) | −0.001 (−0.004, 0.001) |
| Vitamin E (as TE),4 mg/L | 6.1 (4.5, 7.8) | 4.1 (3.0, 5.7) | −1.5 (−2.3, −0.6) | −2.2 (−2.8, −1.6) | −0.7 (−1.8, 0.3) |
| Vitamin E (as TE),3,4 mg/g milk fat | 0.12 (0.09, 0.15) | 0.10 (0.07, 0.14) | −0.02 (−0.03, 0) | −0.02 (−0.02, −0.01) | 0.00 (−0.02, 0.02) |
| Free thiamin, μg/L | 17.4 (12.2, 23.4) | 18.5 (13.9, 27.1) | 3 (0.4, 5) | 3 (1, 6) | 1 (−3, 4) |
| TMP, μg/L | 96 (80, 113) | 96 (72, 110) | −4 (−12, 4) | −2 (−7, 3) | 2 (−7, 12) |
| TPP, μg/L | 4.1 (2.9, 5.7) | 4.0 (2.9, 5.8) | 0.4 (−0.6, 1.4) | −0.3 (−0.9, 0.3) | −0.7 (−1.8, 0.4) |
| Total thiamin (B-1),5 μg/L | 104 (91, 120) | 105 (89, 124) | −1 (−8, 6) | 2 (−3, 6) | 2 (−6, 10) |
| Free riboflavin, μg/L | 11.9 (8.4, 16.1) | 9.3 (5.8, 15.7) | −4 (−6, −1) | 2 (−3, 7) | 6 (−2, 13) |
| FAD, μg/L | 163 (123, 208) | 168 (124, 244) | 45 (−7, 96) | 19 (−2, 39) | −26 (−72, 20) |
| FMN, μg/L | 12.9 (7.6, 24.0) | 14.9 (8.8, 23.6) | 2 (−1, 6) | 0 (−2, 3) | −2 (−5, 2) |
| Total riboflavin (B-2),6 μg/L | 106 (84, 127) | 110 (82, 153) | 19 (−5, 44) | 11 (−0.3. 23) | −8 (−32, 15) |
| Nicotinamide, μg/L | 329 (229, 493) | 197 (127, 290) | −173 (−283, −63) | −175 (−222, −128) | −2 (−103, 99) |
| NAD, μg/L | 3041 (1678, 4909) | 1548 (1114, 2392) | −1670 (−2897, −443) | −1967 (−2633, −1302) | −298 (−1572, 976) |
| Total niacin (B-3),7 μg/L | 901 (620, 1537) | 497 (377, 689) | −480 (−731, −229) | −537 (−680, −399) | −57 (−325, 212) |
| Pantothenic acid (B-5), μg/L | 1425 (1152, 1774) | 1149 (922, 1427) | −215 (−351, −79) | −322 (−410, −233) | −107 (−265, 51) |
| Pyridoxal, μg/L | 88 (64, 116) | 101 (71, 128) | 6 (−7, 18) | 13 (−5, 31) | 8 (−20, 35) |
| Pyridoxine,8 μg/L | 0.32 (0.06, 0.37) | 0.11 (0.05, 0.14) | −0.1 (−0.2, −0.1) | −0.1 (−0.3, 0.1) | 0.0 (−0.2, 0.3) |
| Vitamin B-6,9 μg/L | 88 (65, 116) | 101 (71, 128) | 5 (−8, 18) | 13 (−5, 31) | 8 (−20, 35) |
| Biotin (B-7), μg/L | 7.9 (6.0, 9.5) | 4.7 (2.9, 6.9) | −2.8 (−3.6, −1.9) | −2.2 (−2.9, −1.6) | 0.5 (−0.6, 1.6) |
| Vitamin B-12, μg/L | 0.29 (0.24, 0.36) | 0.28 (0.24, 0.35) | 0.02 (−0.07, 0.11) | −0.02 (−0.06, 0.01) | −0.05 (−0.13, 0.03) |
MN, micronutrient; TE, tocopherol equivalent; TMP, thiamin monophosphate; TPP, thiamin pyrophosphate.
Mean difference (95% CI) determined using change values between 2 and 5 mo postpartum.
n = 1 missing milk fat associated MN value at 2 mo; n = 1 missing α-tocopherol, n = 1 missing milk fat associated MN value at 5 mo.
Vitamin E calculated as the sum of each vitamer expressed as TEs, where 1 mg α-tocopherol = 1 TE, 0.25 mg γ-tocopherol = 1 TE (10).
Vitamin B-1 was calculated based on the measured concentrations for each vitamer and expressed as free thiamin [thiamin + (TPP × 0.707) + (TMP × 0.871)].
Vitamin B-2 was calculated based on the measured concentrations for each vitamer and expressed as riboflavin [riboflavin + (FAD × 0.479) + (FMN × 0.825)].
Vitamin B-3 was calculated as nicotinamide [nicotinamide + (NAD × 0.184)].
Pyridoxine was dichotomized [due to 36.3% (n = 70) & 94.3% (n = 182) of milk concentrations at 0 μg/L at 2 and 5 mo postpartum, respectively] and reported values are based on those with pyridoxine concentrations > 0 µg/L (n = 124 and n = 11).
Vitamin B-6 was calculated as (pyridoxal + pyridoxine).