Adjusted associations* between birth defects and maternal occupation as a nail technician or hairdresser in comparison with non-cosmetologist during pregnancy, National Birth Defects Prevention Study, 1997–2011
| Birth defect | Hairdressers† | Nail technicians | ||||
| n | OR | 95% CI | n | OR | 95% CI | |
| Congenital heart defects | ||||||
| Any heart defect | 26 | 0.8 | 0.5 to 1.2 | 19 | 2.7 | 1.3 to 5.9 |
| Conotruncal defects | 5 | 0.7 | 0.3 to 1.6 | 5 | 3.0 | 1.0 to 8.8 |
| Tetralogy of Fallot | 3 | 0.7 | 0.2 to 2.2 | 3 | 3.5 | 1.0 to 12.9 |
| LVOTO | 5 | 0.8 | 0.3 to 2.0 | NR | ||
| RVOTO | 6 | 1.0 | 0.4 to 2.3 | 4 | 3.2 | 1.0 to 10.4 |
| Pulmonary valve stenosis | 6 | 1.2 | 0.5 to 2.9 | 3 | 3.5 | 0.9 to 12.9 |
| Septal defects | 9 | 0.8 | 0.4 to 1.5 | 7 | 3.1 | 1.2 to 8.1 |
| Atrial septal defect | 7 | 1.0 | 0.4 to 2.2 | 4 | 3.0 | 0.9 to 9.6 |
| Non-heart defects | ||||||
| Neural tube defects | 7 | 0.9 | 0.4 to 2.0 | 4 | 2.6 | 0.8 to 8.4 |
| Anencephaly and craniorachischisis | 3 | 1.4 | 0.4 to 4.5 | NR | ||
| Spina bifida | 4 | 0.8 | 0.3 to 2.4 | NR | ||
| Anotia/microtia | 3 | 2.1 | 0.6 to 6.9 | NR | ||
| Oral clefts | 21 | 1.2 | 0.7 to 2.1 | NR | ||
| Cleft palate | 3 | 0.5 | 0.2 to 1.7 | NR | ||
| Cleft lip w/wo cleft palate | 18 | 1.7 | 1.0 to 2.9 | NR | ||
| Cleft lip with cleft palate | 13 | 2.0 | 1.1 to 3.7 | NR | ||
| Cleft lip without cleft palate | 5 | 1.2 | 0.5 to 3.1 | NR | ||
| Hypospadias | 15 | 1.4 | 0.7 to 2.6 | NR | ||
| Limb deficiency | 4 | 1.0 | 0.4 to 2.9 | NR | ||
| Craniosynostosis | 7 | 1.2 | 0.5 to 2.7 | NR | ||
| Diaphragmatic hernia | 3 | 1.1 | 0.4 to 3.7 | NR | ||
| Gastroschisis | 7 | 1.7 | 0.7 to 3.9 | NR | ||
*Controlling for mother’s smoking status, age at delivery (in continuous years), education level and race/ethnicity.
†Excluding hairdressers with indirect nail product exposure.
LVOTO, left ventricular outflow tract obstruction; NR, not reportable based on n<3; RVOTO, right ventricular outflow tract obstruction; w/wo, with or without.