Table 5.
Zidovudine (AZT) and AZT-glucuronide meconium detection and concentrations by type of AZT exposure in 596 samples
| 7 AZT exposure categories |
N (% of total 596) |
AZT positive meconium n (%) |
Median (range) positiveb meconium AZT concentrations, ng/g |
Median (range, n) positivec meconium AZT-glucuronide concentrations, ng/g |
Median (range) positive meconium AZT-glucuronide/AZT ratio |
|---|---|---|---|---|---|
| Maternal 3rd trimester, L&Da, and neonatal prophylaxis | 323 (54.2%) | 312 (96.6%) | 3292 (102 – 81468) | 7337 (501 – 783582, n=235) | 1.9 (0.06 – 29.3) |
| Maternal 3rd trimester and L&D (no neonatal prophylaxis) | 3 (0.5%) | 2 (66.7%) | 1327 (996 – 1657) | 1575 (1248 – 1903, n=2) | 1.3 (0.8 – 1.9) |
| L&D and neonatal prophylaxis (no 3rd trimester AZT) | 238 (39.8%) | 222 (93.3%) | 1464 (103 – 136595) | 6225 (531 – 105280, n=127) | 1.6 (0.2 – 41.4) |
| Maternal 3rd trimester and neonatal prophylaxis (no L&D) | 2 (0.3%) | 2 (100%) | 1755 (385 – 3125) | 1548 (n=1) | 0.5 |
| L&D only | 3 (0.5%) | 3 (100%) | 2888 (563 – 20165) | 18005 (2263 – 33746, n=2) | 1.2 (0.8 – 1.7) |
| Neonatal prophylaxis only | 27 (4.5%) | 22 (81.5%) | 1413 (189 – 22620) | 4338 (500 – 57823, n=14) | 1.1 (0.4 – 5.3) |
| Maternal 3rd trimester only | 0 |
a
Labor and delivery (L&D) administration
b
AZT LOQ 100 ng/g; median AZT meconium concentrations were significantly different between exposure groups (Kruskal-Wallis chi-square statistic 18.9, P=0.004).
c
AZT-glucuronide LOQ 500 ng/g; median AZT-glucuronide meconium concentrations were not significantly different between exposure groups (Kruskal-Wallis chi-square 5.7, P=0.46).