Every professional woman's life is a fine balancing act between career and family. It is basically not possible for others to guide a lady about this balancing. Every lady does this based upon her own circumstances.
Having said this, specific advice can be given only if detils of educational qualifications and professional background are knowm. In the present case, we do not know your qualification or nature of your present job. So only general advice can be given.
After child-birth, you can go back to your old organisation and seek permission from the authorities to work from home. Nowadays MNCs allow lady-employees (and in some special cases, male employees) to work from your residence. Of course, it may not be possible from some special types of work.
If you want to leave your present job after child-birth but want to have some regular income, you can go for tutoring from your residence. If you can adjust yourself to odd working hours, online tutoring is a very very lucrative option. However, tutoring is not everyboy's cup of tea.
If you have the ability to write, you can start technical writing or blog-writing. For professionals with technical background s and writing skills, technical writing is an attractive option. You can also give it a try.
Caution: Explosive. Handle with care.