The most common nationwide subsidy is 3,600 RMB per child per year, which is basically ineffective. For a woman on maternity leave, the government will subsidize her based on her salary, which can be substantial—in places like Shanghai it could reach 200,000–300,000 RMB—but still not enough to stimulate population growth.
To put it in a darker perspective: the only way to truly boost birth rates would be to reduce women’s rights or compensation, which is unlikely in any civilized country. A historical example is Romania.
So in my understanding, China has only two viable paths: solve the cost of raising children through household robots or by means of coercion, the government could require state-owned enterprise employees and Communist Party members to have children. China has 100 million Party members and roughly tens of millions of SOE employees. SOE employees usually have stable benefits and income, so childbirth could be tied to salary, benefits, or promotion opportunities. To some extent, this could be argued as reasonable—after all, they are supported by taxpayers and arguably should contribute to society. But it still counts as a rather dark idea, and I imagine it would be a last-resort option.