Table 3 Crude and adjusted odds ratios for anencephaly according to agricultural work and the application of pesticides by the parents.
| Variable | Cases | Controls | Crude | Adjusted* | ||||
|---|---|---|---|---|---|---|---|---|
| n | % | n | % | OR | 95% CI | OR | 95% CI | |
| Mothers | ||||||||
| Sometime in life | ||||||||
| Non‐agricultural workers | 110 | 72.85 | 125 | 82.78 | 1 | 1 | ||
| Agricultural workers | 41 | 27.15 | 26 | 17.22 | 2.15 | 1.12–4.16 | 1.47 | 0.79–4.93 |
| Acute risk period (ARP) | ||||||||
| Non‐agricultural workers | 110 | 89.43 | 125 | 93.98 | 1 | 1 | ||
| Agricultural workers | 13 | 10.57 | 8 | 6.02 | 3.67 | 1.02–13.14 | 4.57 | 1.05–19.96 |
| Non‐acute risk period (NARP) | ||||||||
| Non‐agricultural workers | 110 | 80.29 | 125 | 88.03 | 1 | 1 | ||
| Agricultural workers | 27 | 19.71 | 17 | 11.97 | 1.78 | 0.79–4.02 | 1.65 | 0.43–6.39 |
| Fathers | ||||||||
| Sometime in life | ||||||||
| Non‐agricultural workers | 62 | 48.06 | 67 | 60.91 | 1 | 1 | ||
| Agricultural workers | 34 | 26.36 | 29 | 26.36 | 1.27 | 0.69–2.32 | 0.66 | 0.30–1.48 |
| Applicators | 33 | 25.58 | 14 | 12.73 | 2.55 | 1.24–5.20 | 2.17 | 0.86–5.49 |
| Acute risk period (ARP) | ||||||||
| Non‐agricultural workers | 62 | 64.58 | 67 | 75.28 | 1 | 1 | ||
| Agricultural workers | 20 | 20.93 | 13 | 14.61 | 1.66 | 0.76–3.62 | 0.79 | 0.257‐2.36 |
| Applicators | 14 | 14.58 | 9 | 10.11 | 1.68 | 0.68–4.16 | 2.50 | 0.73–8.64 |
| Non‐acute risk period (NARP) | ||||||||
| Non‐agricultural workers | 62 | 65.26 | 67 | 76.14 | 1 | 1 | ||
| Agricultural workers | 14 | 14.74 | 16 | 18.18 | 0.95 | 0.43–2.10 | 0.61 | 0.21–1.74 |
| Applicators | 19 | 20.00 | 5 | 5.68 | 4.11 | 1.45–11.66 | 2.03 | 0.58–7.08 |
| Both parents | ||||||||
| Sometime in life | ||||||||
| Neither is an agricultural worker | 56 | 43.41 | 60 | 54.55 | 1 | 1 | ||
| One is an agricultural worker and/or applicator | 49 | 37.98 | 38 | 34.55 | 1.38 | 0.79–2.42 | 1.02 | 0.54–1.94 |
| Both are agricultural workers and/or applicators | 24 | 18.60 | 12 | 10.91 | 2.14 | 0.98–4.69 | 1.46 | 0.60–3.52 |
| Acute risk period (ARP)† | ||||||||
| Neither is an agricultural worker | 56 | 58.33 | 60 | 70.59 | 1 | |||
| One is an agricultural worker and/or applicator | 36 | 37.50 | 22 | 25.88 | 1.75 | 0.92–3.34 | – | |
| Both are agricultural workers | 4 | 4.17 | 3 | 3.53 | 1.43 | 0.31–6.67 | – | |
| Non‐acute risk period (NARP)† | ||||||||
| Neither is an agricultural worker | 56 | 62.92 | 60 | 70.59 | 1 | |||
| One is an agricultural worker and/or applicator | 24 | 26.97 | 23 | 27.06 | 1.12 | 0.57–2.20 | – | |
| Both are agricultural workers | 9 | 10.11 | 2 | 2.35 | 4.82 | 1.00–23.29 | – | |
*Multivariate model adjusted for:
Mothers: age of the mother, socioeconomic level (family income and education of the mother), adverse reproductive history with previous children, folate intake of the mother, and energy of the mother.
Fathers: age of the father, socioeconomic level (family income and education of the mother), adverse reproductive history with previous children, exposure of the mother to agricultural work during the ARP, work activity of both parents in industry, folate intake of the mother, and energy of the mother.
Both parents: age of the mother, socioeconomic level (family income and education of the mother), adverse reproductive history with previous children, work activity of both parents in industry, folate intake of the mother, and energy of the mother.
†The models were not adjusted due to the low values of the cells. The sum of the cases and controls does not necessarily equal the total due to missing values.
ARP (acute risk period): three months before and one month after the last menstruation; NARP (non‐acute risk period): exposure prior to the ARP.