Long-term separation from family members has become a top reason for migrant workers to consider quitting their jobs, a survey shows.

It says this represents a major challenge for companies to maintain an efficient and stable workforce.

The survey, released on Thursday, also blames enterprises for a lack of awareness about the problem and for insufficient support for their workers.

More than 40 percent of migrant workers said they had left their jobs at least once for family reasons.

The main reasons include taking care of their children, attending to senior family members and to be with their spouses.

The survey was conducted by the Center for Child Rights and Corporate Social Responsibility, a Beijing-based social enterprise, in cooperation with Facilitator, an NGO serving migrant workers.

About 1,500 workers and management staff members at nine factories in the Pearl River Delta and Chong-qing municipality were interviewed last year. The Swedish embassy in China sponsored the study.

More than 80 percent of migrant workers who left their children behind in the countryside said they felt they had failed to play their role as parents.

About 70 percent of respondents said they had a strong sense of guilt and anxiety as a result of family separations and also found it difficult to communicate with their children after long separations.

Hu Xuexiu, a 38-year-old migrant worker from Hunan province, said she felt lonely every day, missing the daughter she left behind in her hometown very much. Hu works at an electronics factory in Zhuhai, Guangdong province.

She said she had considered quitting her job to be with her daughter, who is at high school.

China has more than 61 million children left behind by their migrant worker parents, or one in five children under the age of 18 living separately from their parents, according to the All-China Women's Federation.