Sex During Pregnancy In most cases, sex during pregnancy is safe. In fact, with your doctor's approval, sexual relations can continue until delivery. Chronic Lung Disease If your baby was born premature and needed to be on a respirator, her lungs may have been damaged. This can cause a condition called chronic lung disease (CLD). But CLD can be treated, and as lungs mature the condition can improve. Learn about the symptoms and treatments for CLD. Respiratory Distress Syndrome This disease is one of the most common problems of premature babies. It can cause babies to need extra oxygen and help in breathing. Meconium Aspiration Meconium aspiration occurs when a baby breathes in amniotic fluid containing meconium (the baby's first stools). Pneumothorax Pneumothorax is a lung disorder in which air in the lungs leaks out through holes in the lung tissue into the spaces outside the lung airways. Persistent Pulmonary Hypertension In this condition, a newborn's circulation changes back to the circulation of a fetus, where much of the blood flow bypasses the lungs. The Respiratory System in Babies By about 35 weeks gestation, most babies have developed adequate amounts of surfactant, a substance normally released into the lung tissues to lower surface tension in the airways. This helps keep the air sacs in the lung open. Transient Tachypnea of the Newborn Transient tachypnea of the newborn is a term for a mild respiratory problem of babies that begins after birth and lasts about three days. Apnea of Prematurity It’s a cliché that many new parents need to reassure themselves that the baby is still breathing. But what if your baby really is having breathing problems? A breathing condition called apnea of prematurity affects some babies, especially if they’re born early. But you can learn what symptoms to look for.