I'd liken worries about staying productive while raising children to worries about being able to run a marathon. You're probably safely certain you couldn't do

I'd liken worries about staying productive while raising children to worries about being able to run a marathon. You're probably safely certain you couldn't do it tomorrow, but that says little about your ability to do it 9 months from now and nothing about what the next person is capable off. Ask around and you'll find supremely productive people who do both.