Background It is estimated that at least 200 million children, mostly from developing countries, suffer from developmental delays. Poor hygiene and sanitation conditions are known to influence growth faltering and increased risk of morbidity and mortality, yet little is know about role of these conditions on child growth and development. The study aims to contribute to an understanding of the relationship between family hygiene, sanitary conditions and psychomotor development in the first 3 years of life.

Method A cross sectional household survey was conducted in urban and rural Sindh, Pakistan, by trained personnel. Children aged <3 (n=1244) were assessed at home visits using (1) Bayley's Infant Developmental Scale for psychomotor development; (2) anthropometric status, and (3) socio-economic, hygiene and sanitation conditions via maternal interview. Socioeconomic, hygiene and sanitation indices are created using principal component analyses

Results Rural areas are highly correlated with hygiene index (HI) and sanitation index (SI), as compared to their urban counterparts. Age and sex adjusted SI is highly correlated with socioeconomic index (SEI). Multilevel modelling analysis showed that SI is significantly associated with child's delayed development, stunting and being underweight; while HI is associated with underweight and stunting status of children, independent of SEI and rural-urban neighbourhood.

Conclusion Due to a strong association between hygiene and sanitation conditions and development, recognition should be given to the growth and developmental needs of children living in such conditions.