Extending maternity leave?

Hi mommies. Has anyone decided to extend their maternity leave or plans to? My daughter is turning 3 month soon and I'm on the fence if I should return to work next month. My main concern returning to work is whether I can cope w pumping, the lack of sleep and work altogether. During ML, I sleep on average 4-5 hours in total and get out of bed around 12pm. With work, I really dun know. I plan to extend another 1-2 months. I read that companies will encourage employee to use their paid leave first before taking any unpaid ones. I am hoping to save my paid leave. Can anyone share if it's possible to take unpaid leave this way? Any restrictions or cap? Appreciate some insights, alternatives and advice on the pros and cons too. Thank you