Threats and diseases
Prostitution was even legal in the 15th century, although visiting a prostitute officially was not. That changed at the end of the 16th century when Amsterdam became Protestant. The new city council decided to forbid any prostitution. The politicians threatened men visiting whores with severe measures and the ladies themselves with expulsion. But, as often the case in Amsterdam policies, the threats proved to be mainly verbal.
In daily life, a blind eye was turned to what was going on in the Red Light District, and the next, prosperous 17th Golden Century, even saw a rampant growth in whoredom. An estimated thousand women were selling physical delights for a living in these years. Especially at the end of summer, when the vessels returned from the East Indies, they were incredibly busy entertaining the crew that came back from a long, boring and lonesome journey. While they were making good money, there was also a big problem on the rise. The raging sexually transmitted diseases, like gonorrhea and syphilis, were often fatal.