When we have a squarefree, negative integer $d$, class number of $\mathbb{Q}\sqrt{d}$ is equal to the number of positive definite reduced binary quadratic forms of discriminant $d$ or $4d$ depending on whether $d \equiv_{4} 2,3$ or $d \equiv_4 1$.
Do we have a such relation when we have a positive $d$ and real quadratic number field $\mathbb{Q}\sqrt{d}$? Can we say something like 'the class number of the number field is equal to the negative definite quadratic forms of fixed discriminant' ?