Q: MY sister has a four-month-old baby girl who was two months premature. She only weighs about 4kg. What causes prematurity? Will she be normal when she grows up? She looks so funny and tiny now. el1 Dr Rose writes: Prematurity, or the birth of a baby before 37 weeks' gestation, occurs in about 10 per cent of all births. The most common maternal cause of premature labour is pre-eclampsia, a condition where the woman retains fluid during the second half of pregnancy. In addition, women with diabetes, hypertension and heart disease are more likely to go into labour prematurely. Multiple pregnancies account for about 15 per cent of premature births. Premature babies are smaller and look different from full-term infants. At birth, they lack subcutaneous fat, have thin, gelatinous skin and are covered with fine, downy hair called lanugo. Because the baby's internal organs, especially the lungs, are immature, they usually need to be supported and monitored in an incubator until they can function independently. They often have difficulty maintaining their body temperature, and sucking and feeding, and are at increased risk of brain haemorrhage, low bloodsugar and jaundice. The later the gestational age of the pregnancy, the greater the likelihood that the baby will survive. With modern medical techniques, infants as young as 23 weeks' gestation and less than 1kg are now surviving. The emotional and financial toll on the parents can be significant. In some cases, bonding can be disrupted. Most premature babies catch up with full-term babies by the end of their first year of life. As long as she has no persistent medical problems, your sister's baby should develop normally. Q: WHILE running during the cooler days we had in Hongkong a few months ago my chest felt really tight and I couldn't get enough air in. This happened during the first few minutes of my run. As I continued to run I felt a little better. I am a fit 29-year-old male and I thought that I was in excellent condition. I have no medical problems. Any ideas what this might be? Dr Rose writes: You may be suffering from exercise-induced asthma, a condition found in up to 85 per cent of allergenic asthmatic patients and a few non-allergenic patients. Symptoms include a rapid heart rate, wheezing, a high pitch sound heard at the end of expiration, coughing, shortness of breath and difficulty in breathing beginning five to 10 minutes after the start of the exercise activity. Factors which may exacerbate this phenomenon include cold air, low humidity, air pollution, and high air pollen concentrations. People who have a history of allergies and nasal blockages are most at risk since the inhaled air is not humidified and warmedin the nasal passages. Exercise activities most likely to cause asthma include running, bicycling, basketball and soccer and, in cold climates, ice hockey and skiing. The good news is that most patients with exercise-induced asthma can participate fully in their activity with proper pre-activity medication. Consult your physician for a diagnosis and to determine which medication is appropriate for you. Q: A FEW years ago my mother lost her ability to taste food. This was most distressing as she was an enthusiastic cook and loved to have friends over for fancy dinner parties. Since this has happened she is most reluctant to entertain guests. What is this caused by? Dr Rose writes: Stomatitis, a condition in which the mouth is inflamed, mouth cancer, radiation therapy, smoking and the side-effects of certain drugs can all lead to diminished or complete loss of taste. Nerve damage due to a head injury, or a tumour or surgery on the neck or head can also be contributing factors. Loss of taste most commonly occurs in combination with loss of the ability to smell. Anyone who has suffered from a cold or flu knows what it is like to temporarily lose the ability to taste and smell. In rare cases, individuals lose the ability to taste without losing their sense of smell. Under these circumstances, a chronically dry mouth is a contributing factor. A certain amount of saliva needs to be present in the mouth so that the taste buds can detect the substances responsible for flavours. You did not say how old your mother is, but the ability to taste does degenerate with age. Let's hope that with some reassurance, and a little help in the kitchen, your mother will once again begin to find pleasure from entertaining. Dr Rose Ong is a certified family physician licensed in the United States. She welcomes enquiries but cannot answer them individually. Specific questions should be addressed to your own physician. Additional enquiries: Peak Corporate Health Management, 525-6600, fax 525-8100.