1 month old baby with phlegm in the throat, the following conditions are common: 1, congenital laryngeal wheezing, because the baby in the fetal period the mother lack of calcium, or in the postnatal period was not given timely supplementation of vitamin D or premature babies, so that the laryngeal cartilage is poorly developed, in breathing, eating milk easily appear wheezing sound, similar to the presence of phlegm. After giving vitamin D and calcium supplements, it will improve significantly with age and even disappear and heal after the age of 1 year. 2. Pneumonia in small infants, the baby is small and the lung signs are not typical, often without cough, fever, wheezing and other symptoms, just showing phlegm in the throat, increased respiration and poor milk eating, so go to the hospital in time and have an X-ray chest examination if necessary.