Generally speaking, no. There is probably an implied licence from the owner of copyright in the sweater, afghan, or whatever the pattern is for, permitting you to make more than one. What you can do with the multiple copies once you\’ve made them, however, is another question.
Let\’s assume that there is copyright in the printed pattern and copyright in the sweater. These copyrights do not have to be owned by the same person, but for the sake of simplicity, we will further assume that it is the same person.
Copyright in the pattern may be invoked to prevent you from distributing copies of the pattern. However, the copyright owner cannot use copyright in the pattern stop you from using the pattern (to make the sweater).
Copyright in the sweater may be invoked to prevent you from making copies of the sweater. This is contrary to the fact that you are entitled to use the pattern, but it can be explained by an implied licence. When you obtained your legal copy of the pattern, you also received tacit permission to make the sweater. After all, what else is the pattern for? Also, it\’s likely that this tacit permission does not limit you to making only one–you could make a sweater for every member of your family.
The tacit permission you have to make several copies of the sweater (your implied licence) depends on the usual practice in the relevant industry, and the behaviour of the parties. If this were a matter for a court to decide, the parties to the lawsuit would present experts who would testify as to the common practice.