如何在MySQL查询中使用MONTHNAME来匹配月份

I'm building a query so I can get a list of new users by month:

public function getNewUsers($month) {

        $month = date('F', strtotime($month));

        $sql = "SELECT * FROM `{$this->table}` WHERE MONTHNAME(`account_creation_date`) = {$month} ORDER BY `id` DESC";
        $stmt = $this->pdo->prepare($sql);
        $stmt->execute([$month]);

        if ($stmt->rowCount() == 0) return null;

        $users = $stmt->fetchAll(PDO::FETCH_NAMED);

        foreach ($users as &$user) {

            $user = $this->applyRelations($user);

        }

        return $users;

    }

An example of "account_creation_date" value is "08/08/2019 4:55 pm"

Im trying to pass in a month name like "August" and have the query convert the account_creation_date values to their month names.

Although I'm getting no errors, nothing is returning when the query is executed.

How can I accomplish this? Is MONTHNAME what I want?

Thanks!