The dead infant was found on Monday wrapped in a towel at a waste management company facility, the Koblenz district state prosecutor's office said.
The woman told authorities she thought the child was already dead when she put it in a restaurant bio-waste skip. Initial evidence points to the woman, who worked in the restaurant kitchen, had concealed her pregnancy, then secretly gave birth to the living child in the ladies room and disposed of the child in the dumpster.
The state prosecutor's office said the woman is married and has three children aged six, seven and nine-years-old.
Germany has been plagued with a spate of gruesome infanticide cases in the last few years which have shocked the country. One woman who killed nine of her babies was sentenced to 15 years in prison in early April.
In May, a 44-year-old woman was arrested when her family found three dead babies in her freezer near Bonn.