Not exactly. The central banks acting as a lender of last resort encourage the commercial banks to create money in this way, but be assured that the actual creation occurs whether the bank needs to borrow money or not. The definition of money supply looks to the balances in checking accounts, and creating and disbursing a loan increases the balance in a checking account (while simultaneously increasing the negative balance in a loan account, but loan balances don't shrink the money supply), and as that money is spent it increases balances in someone else's checking account.