Table 1. Baseline demographic and clinical characteristics of mothers in the pregnancy cohort—Salvador, Brazil, January 2015 to December 2016.
| Characteristics | ZIKV exposed* No. (%) or median (IQR) (N = 13) | ZIKV unexposed† No. (%) or median (IQR) (N = 33) | p-value |
|---|---|---|---|
| Median mother age, median (IQR), years | 25 (21–31) | 25 (20–30) | 0.98 |
| Black ethnicity‡ | 7 (53.8%) | 22 (66.7%) | 0.63 |
| Lower educational level‡ | 5 (38.5%) | 10 (30.3%) | 0.84 |
| Previous pregnancies | |||
| 0 | 3 (23.1%) | 10 (30.3%) | 0.79 |
| 1–3 | 6 (46.2%) | 16 (48.5%) | 0.87 |
| ≥ 4 | 4 (30.8%) | 7 (21.2%) | |
| Medical history | |||
| Arterial hypertension | 0 (0.0%) | 3 (9.1%) | 0.72 |
| Osteoarthritis | 0 (0.0%) | 1 (3.0%) | 0.99 |
| Prior sexually transmitted infection | 1 (7.7%) | 1 (3.0%) | 0.99 |
| Health problems during pregnancy | |||
| Urinary infection | 5 (38.5%) | 9 (27.3%) | 0.68 |
| Vaginal fungus infection | 2 (15.4%) | 4 (12.1%) | 0.99 |
| TORCH infections | 0 (0.0%) | 0 (0.0%) | NA |
| HIV infection | 0 (0.0%) | 0 (0.0%) | NA |
| Symptoms during pregnancy | |||
| Fever | 4 (30.8%) | 6 (18.2%) | 0.57 |
| Rash | 1 (7.7%) | 3 (9.1%) | 0.99 |
| Conjunctival injection | 0 (0.0%) | 0 (0.0%) | NA |
| Myalgia and arthralgia | 1 (7.7%) | 0 (0.0%) | 0.99 |
| Headache | 3 (23.1%) | 3 (9.1%) | 0.42 |
| Median of prenatal care, median (IQR) | 4 (2–8) | 6 (4–8) | 0.28 |
| Median of prenatal ultrasonography, median (IQR) | 3 (2–4) | 3 (2–4) | 0.82 |
| Prenatal ultrasonography with malformations | 0 (0.0%) | 0 (0.0%) | NA |
| Nutritional supplement use | |||
| Ferrous sulphate | 10 (76.9%) | 28 (84.8%) | 0.80 |
| Folic acid | 8 (61.5%) | 24 (72.7%) | 0.48 |
| Other vitamins | 2 (15.4%) | 6 (18.2%) | 0.99 |
| Caesarean delivery | 9 (69.2%) | 24 (72.7%) | 0.99 |
| Birth characteristics | |||
| Gestational age at birth, median (IQR) weeks | 40 (39–40) | 40 (39–40) | 0.82 |
| Preterm birth | 1 (7.7%) | 0 (0.0%) | 0.26 |
| Full term | 11 (84.6%) | 33 (100.0%) | |
| Postterm birth | 1 (7.7%) | 0 (0.0%) | 0.26 |
| Mothers’ ZIKV NS1 BOB ELISA result | |||
| Positive | 13 (100.0%) | 26 (78.8%) | NA |
| During pregnancy | 13 (100.0%) | 0 (0.0%) | NA |
| Before pregnancy | 0 (0.0%) | 25 (75.8%) | NA |
| After pregnancy | 0 (0.0%) | 1 (3.0%) | NA |
| Negative | 0 (0.0%) | 7 (21.2%) | NA |
* ZIKV-exposed mothers with seroconversion to ZIKV during pregnancy.
† Unexposed: mothers who were not infected during pregnancy (without seroconversion or seroconversion before or after pregnancy).
‡ Black ethnicity was compared with White (n = 3) and Mixed ethnicities (n = 14). Lower educational level was defined as no education or only up to first or second grade completed.
TORCH, Toxoplasmosis, Rubella, Cytomegalovirus, Herpes infections and Others.
NA, not applicable.
ZIKV NS1 BOB, ZIKV nonstructural protein 1 blockade-of-binding ELISA.