Table 1.
Factors associated with mother-to-child HIV transmission
| N | Value | Mothers with infant HIV PCR results available (N = 1,813) | Mothers with HIV-negative infants (N = 1,754) | Mothers with HIV-positive infants (N = 59) | Crude OR (95% CI) | Adjusted OR (95% CI) | |
|---|---|---|---|---|---|---|---|
| Age | 1,813 | 29 years (SD +/− 5) | |||||
| ≤ 24 years | 327 | 315 (18.0%) | 12 (20.3%) | 1.0 | 1.0 | ||
| 25 – 29 years | 622 | 601 (34.3%) | 21 (35.6%) | 0.9 (0.5 – 1.9) | 0.9 (0.4 – 2.0) | ||
| 30 – 34 years | 560 | 540 (30.8%) | 20 (33.9%) | 1.0 (0.5 – 2.0) | 1.1 (0.5 – 2.4) | ||
| ≥ 35 years | 304 | 298 (17.0%) | 6 (10.2%) | 0.5 (0.2 – 1.4) | 0.6 (0.2 – 1.6) | ||
| Education | 1,813 | ||||||
| Secondary or tertiary | 878 | 858 (48.9%) | 20 (33.9%) | 1.0 | |||
| None or primary | 715 | 687 (39.2%) | 28 (47.5%) | 1.8 (1.0 – 3.1) | 1.8 (1.0 – 3.2) | ||
| Unknown | 220 | 209 (11.9%) | 11 (18.6%) | 2.3 (1.1 – 4.8) | 2.3 (1.1 – 5.1) | ||
| Marital status | 1,753 | ||||||
| Married/cohabiting | 1,637 | 1,585 (93.4%) | 52 (92.9%) | 1.0 | |||
| Other | 116 | 112 (6.6%) | 4 (7.1%) | 1.1 (0.4 – 3.1) | |||
| GA at 1st ANC visit | 1,813 | 21 weeks (SD +/− 6) | |||||
| ≤ 20 weeks | 605 | 584 (33.3%) | 21 (35.6%) | 1.0 | |||
| 21 – 27 weeks | 980 | 948 (54.0%) | 32 (54.2%) | 0.9 (0.5 – 1.6) | |||
| ≥ 28 weeks | 228 | 222 (12.7%) | 6 (10.2%) | 0.8 (0.3 – 1.9) | |||
| BMI | 977 | ||||||
| < 25 kg/m2 | 562 | 539 (57.6%) | 23 (56.1%) | 1.0 | |||
| 25 – 29 kg/m2 | 360 | 343 (36.6%) | 17 (41.5%) | 0.9 (0.4 – 1.9) | |||
| ≥ 30 kg/m2 | 55 | 54 (5.8%) | 1 (2.4%) | 0.4 (0.1 – 3.0) | |||
| Hemoglobin | 1,813 | 11.0 g/dL (SD +/− 1.6) | |||||
| ≥ 10.0 g/dL | 977 | 957 (54.6%) | 20 (33.9%) | 1.0 | 1.0 | ||
| 8.0 – 9.9 g/dL | 267 | 254 (14.5%) | 13 (22.0%) | 2.5 (1.2 – 5.0) | 1.7 (0.8 – 3.6) | ||
| ≤ 7.9 g/dL | 29 | 28 (1.6%) | 1 (1.7%) | 1.7 (0.2 – 13.2) | 0.8 (0.1 – 6.9) | ||
| Not done | 540 | 515 (29.4%) | 25 (42.4%) | 2.3 (1.3 – 4.2) | 2.3 (1.2 – 4.5) | ||
| Syphilis screen | 1,813 | ||||||
| RPR non-reactive | 1,316 | 1,275 (72.7%) | 41 (69.5%) | 1.0 | 1.0 | ||
| RPR reactive | 40 | 35 (2.0%) | 5 (8.5%) | 4.4 (1.7 – 11.9) | 3.8 (1.3 – 10.7) | ||
| Not done | 457 | 444 (25.3%) | 13 (22.0%) | 0.9 (0.5 – 1.7) | 0.9 (0.5 – 1.7) | ||
| CD4+ count at entry | 1,813 | 231 cells/uL (IQR 164 – 329) | |||||
| ≥ 350 cells/uL | 250 | 246 (14.0%) | 4 (6.8%) | 1.0 | 1.0 | ||
| 200–349 cells/uL | 511 | 501 (28.6%) | 10 (16.9%) | 1.2 (0.4 – 4.0) | 0.8 (0.2 – 2.6) | ||
| < 200 cells/uL | 446 | 422 (24.1%) | 24 (40.7%) | 3.5 (1.2 – 10.2) | 2.0 (0.6 – 6.3) | ||
| Not done | 606 | 585 (33.4%) | 21 (35.6%) | 2.2 (0.8 – 6.5) | 1.9 (0.6 – 5.8) | ||
| GA at delivery | 1,813 | 38 weeks (SD +/− 4) | |||||
| 37 – 41 weeks | 1,069 | 1,033 (58.9%) | 36 (61.0%) | 1.0 | |||
| < 32 weeks | 65 | 63 (3.6%) | 2 (3.4%) | 0.9 (0.2 – 3.9) | |||
| 32 – 36 weeks | 445 | 428 (24.4%) | 17 (28.8%) | 1.1 (0.6 – 2.1) | |||
| ≥ 42 weeks | 234 | 230 (13.1%) | 4 (6.8%) | 0.5 (0.2 – 1.4) | |||
| Birth weight | 1,792 | 2,900 g (SD +/− 400) | |||||
| ≥ 2,500 g | 1,568 | 1,519 (87.7%) | 49 (83.1%) | 1.0 | 1.0 | ||
| < 2,500 g | 224 | 214 (12.3%) | 10 (16.9%) | 1.5 (0.7 – 2.9) | 1.2 (0.6 – 2.5) | ||
| Duration of antenatal HAART | 1,813 | 13 weeks (IQR 8 – 19) | |||||
| ≥ 13 weeks | 1,188 | 1,161 (66.2%) | 27 (45.8%) | 1.0 | 1.0 | ||
| 9 – 12 weeks | 196 | 189 (10.8%) | 7 (11.9%) | 1.6 (0.7 – 3.7) | 1.8 (0.7 – 4.8) | ||
| 5–8 weeks | 242 | 234 (13.3%) | 8 (13.6%) | 1.5 (0.7 – 3.3) | 2.0 (0.8 – 5.1) | ||
| ≤ 4 weeks | 187 | 170 (9.7%) | 17 (28.8%) | 4.3 (2.3 – 8.1) | 5.5 (2.6 – 11.7) |
GA: gestational age; ANC: antenatal care; BMI: body mass index; SD: standard deviation; IQR: interquartile range; OR: odds ratio; CI: confidence interval