Comorbidity and poor birth outcome for mild microcephaly versus normocephaly
| Mortality/morbidity | Mild microcephaly (n=2102) | Normocephaly (n=42 034) | OR | |||
| Infants (n) | Prevalence per 1000 | Infants (n) | Prevalence per 1000 | Unadjusted OR (95% CI) | Adjusted OR* (95% CI) | |
| In-hospital mortality | 5 | 2.0 | 85 | 2.0 | 1.18 (0.48 to 2.90) | 1.21 (0.49 to 3.00) |
| Preterm (33–36 weeks) | 80 | 38.4 | 3470 | 82.6 | 0.45 (0.36 to 0.55) | 0.45 (0.35 to 0.56) |
| 1 min Apgar score <8 | 45 | 21.4 | 939 | 22.3 | 0.96 (0.71 to 1.30) | 0.98 (0.72 to 1.33) |
| 5 min Apgar score <8 | 6 | 2.9 | 141 | 3.4 | 0.85 (0.38 to 1.93) | 0.83 (0.37 to 1.90) |
| Necrotising enterocolitis | 3 | 1.6 | 49 | 1.2 | 1.23 (0.38 to 3.93) | 1.26 (0.39 to 4.05) |
| Intracranial haemorrhage | 9 | 3.2 | 125 | 3.0 | 1.44 (0.73 to 2.84) | 1.58 (0.80 to 3.15) |
| Bronchopulmonary dysplasia | 1 | 0.4 | 21 | 0.5 | 0.95 (0.13 to 7.08) | 1.03 (0.14 to 8.04) |
| Birth hypoxia | 35 | 16.2 | 594 | 14.1 | 1.18 (0.84 to 1.67) | 1.21 (0.85 to 1.71) |
| Feeding difficulties | 103 | 55.0 | 2243 | 53.4 | 0.91 (0.75 to 1.12) | 0.89 (0.72 to 1.09) |
| Signs of seizure | 1 | 0.5 | 27 | 0.7 | 0.74 (0.33 to 5.63) | 0.76 (0.34 to 5.66) |
| Sepsis of newborn | 5 | 2.4 | 90 | 2.1 | 1.11 (0.45 to 2.74) | 1.09 (0.44 to 2.68) |
| Respiratory distress syndrome | 14 | 6.3 | 435 | 10.3 | 0.64 (0.38 to 1.09) | 0.71 (0.42 to 1.22) |
| Length of stay >7 days† | 197 | 93.7 | 3916 | 93.2 | 1.01 (0.87 to 1.17) | 1.07 (0.91 to 1.39) |
| Length of stay (mean±SD, day) | 3.84±3.66 | 3.97±3.21 | P=0.11 | |||
*Models contain mild microcephaly (vs normocephaly) as the exposure, and birth issues as outcomes, and are adjusted for infant gender, parity, maternal age, ethnicity, education, TORCH agents, exposure to teratogens, pre-eclampsia, diabetes mellitus and chronic illness.
†Infant in-hospital deaths were excluded for the calculation of length of stay.
TORCH, Toxoplasma gondii, rubella virus, cytomegalovirus, herpes simplex virus.