In the first days or weeks after birth you may notice that you sweat much more, especially at night. Some women even wake up with their pyjamas or sheets soaked. It can be uncomfortable and even surprising, but it is very common at this stage.
During pregnancy, your body retained more fluids and increased its blood volume to meet the needs of the pregnancy. After birth, it no longer needs this extra volume and begins to eliminate it, mainly through urine and sweat. The major hormonal shift that happens after birth also contributes to these episodes of sweating.