Characteristics of the study population by infant HIV exposure status, South Africa, 2010
| HIV-unexposed infant n=7071 Nw=875 220 (weighted) | HIV-exposed infant n=3107 Nw=412 634 (weighted) | |||
|---|---|---|---|---|
| Maternal characteristics | Weighted% | 95% CI | Weighted% | 95% CI |
| Mother | 96.8 | 96.2 to 97.2 | 96.9 | 96.3 to 97.5 |
| Other caregiver | 3.2 | 2.8 to 3.8 | 3.1 | 2.5 to 3.7 |
| Maternal age mean (range) | 25.9 (13 to 49) | 27.7 (15 to 46) | ||
| Married status* | ||||
| Single | 72.6 | 70.8 to 74.4 | 78.4 | 76.4 to 80.5 |
| Married/cohabiting | 27.1 | 25.3 to 28.8 | 20.2 | 18.2 to 22.2 |
| Widow/divorced | 0.2 | 0.1 to 0.3 | 0.8 | 0.5 to 12 |
| No information | 0.1 | 0.03 to 0.2 | 0.6 | 0.3 to 0.8 |
| Education level* | ||||
| None | 2.0 | 1.3 to 2.0 | 2.6 | 2.0 to 3.2 |
| Grade 1–7 | 13.4 | 12.4 to 14.4 | 18.2 | 16.7 to 19.8 |
| Grade 8–12 | 77.8 | 76.7 to 79.3 | 75.6 | 73.8 to 77.5 |
| Grade 12+ | 6.5 | 5.7 to 7.3 | 2.7 | 2.1 to 3.4 |
| Missing | 0.4 | 0.3 to 0.6 | 0.8 | 0.5 to 1.1 |
| SES* | ||||
| Average† | 70.5 | 68.5 to 72.6 | 64.3 | 61.6 to 67.0 |
| Lower | 14.5 | 12.7 to 16.2 | 23.1 | 20.5 to 25.7 |
| Lowest | 15.0 | 13.7 to 16.4 | 12.6 | 11.1 to 14.1 |
| Parity* | ||||
| 1 | 41.9 | 40.6 to 43.2 | 21.5 | 19.8 to 23.2 |
| 2 | 28.6 | 27.5 to 29.8 | 36.6 | 34.7 to 38.5 |
| ≥3 | 26.8 | 25.6 to 28.0 | 39.5 | 37.7 to 41.3 |
| Missing | 2.6 | 2.2 to 3.0 | 2.4 | 1.9 to 2.8 |
| Number of live children* | ||||
| 1 | 45.1 | 43.7 to 46.4 | 27.2 | 25.4 to 28.9 |
| 2 | 28.4 | 27.9 to 29.4 | 37.5 | 35.7 to 39.3 |
| ≥3 | 23.9 | 22.8 to 25.1 | 33.0 | 31.2 to 34.7 |
| Missing | 2.6 | 2.2 to 3.0 | 2.4 | 1.9 to 2.8 |
| Planned pregnancy* | ||||
| Yes | 39.7 | 38.1 to 41.3 | 35.5 | 33.3 to 37.8 |
| No | 57.2 | 55.6 to 56.9 | 61.4 | 59.1 to 63.6 |
| Missing | 3.1 | 2.6 to 3.5 | 3.1 | 2.5 to 3.7 |
| Number of ANC visits | ||||
| Had 1 ANC | 96.5 | 96.0 to 97.0 | 96.4 | 95.8 to 96.9 |
| Had <1 ANC | 3.5 | 3.2 to 4.0 | 3.6 | 3.1 to 4.2 |
| Gestational age of first ANC visit (weeks) | ||||
| ≤12 | 23.2 | 22.0 to 24.4 | 20.0 | 18.3 to 21.7 |
| 13–16 | 13.5 | 12.5 to 14.6 | 13.6 | 12.3 to 14.9 |
| 17–20 | 19.1 | 18.0 to 20.2 | 18.9 | 17.1 to 20.7 |
| 21–24 | 14.9 | 13.8 to 15.9 | 17.6 | 16.0 to 19.4 |
| 25–28 | 9.3 | 8.3 to 10.2 | 9.3 | 8.1 to 10.5 |
| 29–32 | 2.2 | 1.8 to 2.5 | 2.0 | 1.5 to 2.4 |
| 33–36 | 0.6 | 0.4 to 0.8 | 0.7 | 0.4 to 1.0 |
| 37+ | 0.7 | 0.5 to 0.9 | 0.9 | 0.5 to 1.2 |
| Missing | 16.5 | 14.7 to 18.4 | 17.0 | 14.7 to 19.3 |
| Infant characteristics | ||||
| Infant sex (male) | 51.2 | 50.0 to 52.4 | 49.1 | 47.1 to 51.1 |
| Infant's birth weight* | ||||
| <2.5 kg | 11.4 | 10.4 to 12.4 | 13.4 | 12.1 to 14.7 |
| ≥2.5 kg | 88.6 | 87.6 to 89.6 | 86.6 | 85.3 to 87.9 |
*p<0.05 (Rao-Scott χ2 test) Nw=weighted population number.
†‘Average’ SES in this population would be low compared with SES of groups using private healthcare or living in ‘developed’ countries.
ANC, antenatal care; SES, socioeconomic status.