It is important to urinate soon after the birth (within an hour or two), and keep the bladder empty in the early days following. A full bladder can inhibit the uterus from contracting and increase bleeding after the birth. Urine may sting or burn as it passes over injured tissues and can be painful if stitches were necessary. (Although in most cases. stitches will hold together injured tissues and usually reduce sensations of stinging).
The hospital staff may offer you sachets of urinary alkalinisers that can be taken for a day or two after the birth. These make the urine less acidic, and therefore less likely to sting as you pass urine. One to two sachets is added to a glass of water and taken every 6 to 8 hours. It will take a few hours for the first dose to take effect. If you have your baby at home, they can be bought over the counter at any chemist.
Most women will urinate large volumes in the first couple of days, as their body eliminates excess fluids that were accumulated to increase the blood volume required during the pregnancy. If you had fluid retention and swelling, this may temporarily become worse, then slowly improve over the next couple of weeks, as the body adjusts. For more information and strategies about urinating after birth you can read
difficulty in passing urine after the birth.
Thankfully, most women will not need to open their bowels until a few days after the birth. This is not regarded as constipation, rather an after effect of having diarrhoea during prelabour and/or early labour, possibly opening your bowels during the pushing phase of the birth, and the natural slowing of the bowel's movement during labour. However, some women may confuse a feeling of 'fullness' in their lower body (as a result of the swollen tissues around the vagina, perineum and anus) as a 'need' to open their bowels, even though this may not be forthcoming.