It is the blood discharged from the womb during childbirth and after which might continue for a few days.
The duration: The maximum duration of Nifas is 10 days after giving birth.
The blood discharged during childbirth is Nifas but these hours are not counted within the ten Nifas days.
How to count the days?
This is done in the same way as counting the days for Haydh. If Nifas starts during the day, every 24 hours from that hour is one day. And if it starts during the night, she counts from the next day — from Fajr till Maghrib as one day, and then, until the next day Maghrib as another day, and so on and so forth.
Question: What about the blood discharged during miscarriage?
This is also considered Nifas. But some jurists say there is no Nifas if an embryo is miscarried.
Question: What is the ruling if the blood continues after 10 days?
If the blood stopped by the 10th day, it is all Nifas. But if it continues after the 10th day, there are two situations: If the lady has a habit of duration in her Haydh, the number of Nifas days will be equal to the duration of her Haydh days, and the rest will be Istihadha. So for example, if her duration of Haydh is 7 days, then her Nifas will also be 7 days. Any subsequent days will be considered as Istihadha.
And for others, the first 10 days will be Nifas and the rest is Istihadha.
Another question: is there Nifas by Caesarean section?
If there is discharge from the womb, it will be Nifas. But the blood coming from the cut wound or the surgical cut is not Nifas.
Finally, the restrictions for a lady in Nifas is the same as Haydh. So as an obligatory precaution, she has to refrain from all that a lady in Haydh has to refrain from.