Sometimes, before a baby is born, fluid can build up in the space around the lungs inside the chest. This is called a fetal pleural effusion. In most cases, this is spotted during a routine pregnancy scan. The fluid can press on the developing lungs, which may stop them from growing as well as they should.
Some babies need treatment before birth to drain the fluid, and many need extra support with breathing after they are born.
Sometimes this condition can occur as part of a condition affecting other areas of the body, and sometimes it happens without affecting other body systems. We do not understand enough about how well the lungs grow and work in children who had this problem before birth, which is why we are investigating this as part of our research.