No. It is a legal requirement and work pass condition for all employers to buy and maintain medical insurance for their:

• Work Permit holders (including migrant domestic workers)
• S Pass holders

The medical insurance protects employers against large medical bills incurred by their workers which employers have to be responsible for under the law. Therefore, you are encouraged to buy insurance with a higher coverage to better protect yourself from large medical bills.

This information is sourced from MOM.