回复：父母探亲签证延期问题。

1.Yes, but you need to prepare well presenting a detailed plan to CIS. Taking care of baby won't work and will make thing worse. But you can say that your parents want to be here to celebrate the birth of your baby, which is a good reason.
2. It is ture that your parents' next visa will be hard after extention.
3. Usually, they need to stay in China for another year before applying for another B1 visa.