As soon as your stomach expands, your navel, the scar of your own umbilical cord, is stretched. Even if you have a deep navel (an "innie") when you are not pregnant, you will see that your navel first flattens and then even protrudes outwards. Some think this is not a problem, others find it irritating to have an extra bump on top of the already big belly. A plaster over the navel can ensure that it does not stand out through your clothes.
In most cases it is a temporary condition that resolves after pregnancy. If the skin springs back to pre-pregnant sizes, the belly button also goes back. In a small group of women, the weak connection in the navel can become detached, so that the outie remains.
There is no medical reason for removing a belly button ring during pregnancy. Most women get a different navel shape later in the pregnancy, so wearing the ring can be annoying. Also ask the doctor what his preference is, some midwives want you to remove the ring during birth.
|A mix of both|
Even if you've had an innie all your life, you will probably have an outtie during your pregnancy. Talk with your doctor if you have any doubts.
Pain in the navel can be caused by innocent things such as the stretching of the skin or pain in the muscles. A stretched navel can also result in a hernia umbilicalis. (umbilical hernia) If your navel is painful when coughing, it is best to have it checked by a doctor.
Due to the stretching, the skin can become irritated and itchy. Try to keep it moisturised.
From angelababy In Q&A