It is known that many drugs cross the placenta and can harm a baby. You should remember that smoking, drinking alcohol and the use of non-prescription drugs would all harm a baby. A kidney that is already diseased might suffer some further damage during pregnancy. This is more likely if the kidney disease is severe at the start. People with kidney failure who expect to need dialysis in the future may find that pregnancy hastens their progression to dialysis, but rarely it is necessary to start dialysis during pregnancy.
Dialysis needs to be done more frequently, sometimes every day.
Having a kidney transplant does not rule out pregnancy. A transplant that is functioning very well gives the best chance of a perfectly normal pregnancy. If the transplant is not absolutely normal, then all the complications noted above will apply, including the chances of a deterioration in the function of the transplant itself. It is essential to take anti-rejection therapy throughout pregnancy, and careful attention to drug doses will be needed. Your GP and the team who normally look after your kidney disease will keep a close eye on you.