It is very common that the baby burps because the diaphragm suddenly contracts hard. Generally, hiccups will stop after a short time, which is harmless to the baby. It will naturally ease when you grow up. But if the baby burps for a long time or has frequent attacks, it will make the "caregiver" a little uncomfortable. Babies burp because the diaphragm suddenly contracts strongly, accompanied by involuntary "burping". Compared with older children, most babies don't seem to feel any discomfort unless they burp for a long time, which will interfere with normal life such as diet.
Fetal burping is not a sign of good lung development. Generally, fetal hiccups have little to do with well-developed lungs, but only the performance of his diaphragm spasm. If you want to know whether the fetus has abnormal lung development, it is mainly through regular prenatal examination. As long as the prenatal examination results are normal, don't worry too much.
Some pregnant women may feel the baby burping in the second or third month of pregnancy, or see the baby burping in the mother's stomach during prenatal ultrasound examination. However, the age at which babies frequently burp is just a few months before birth, and usually it will improve after 1 year.