I am a 24-year-old man. Over the last year, I have been more and more frequently waking up in the morning to discover myself sleeping on my stomach, arms crossed beneath my forehead and my hands completely numb as a result. Some mornings it takes five minutes or more for me to regain movement and feeling in my fingers. This is nothing like the position I went to sleep in the night before (I sleep on my side). Am I in danger of doing permanent damage to my hands, and what can I do to prevent it? D.S., Jerusalem Dr. Arie Oksenberg of the sleep disorders unit at Beit Loewenstein Rehabilitation Hospital in Ra'anana comments: The fact that your arms and fingers get numbed is most probably due to the fact that you apply pressure with your head on your arms and fingers for a relatively long period and, as a consequence, the blood supply to those areas is somewhat abnormal and the numbness is a direct result of this quite frequent phenomenon. However, do not worry! Nothing serious will happen to you. Two different things may help you in this case: The first one is to use a cloth belt that has a pocket in it. Put a tennis ball in the pocket and position it on your stomach side. Whenever you try to sleep in the prone posture, the tennis ball will make you uncomfortable and force you to roll over on your side or back without waking up. We have successfully tried this technique to avoid the supine posture during sleep. The other possibility is the use of a special pillow that won't allow you to put your arms beneath your head. You can find more information through a search of the Internet. I am a 54-year-old woman who has a lot of difficulty traveling in a plane or bus for long periods of time. My legs feel restless and extremely uncomfortable. I don't know what the condition is called, but I have been told that it might be patella femoral syndrome. Aside from some feet or leg exercises while seated or periodic walks on a plane, what will give me relief? B.Z., Jerusalem Dr. Naama Constantini, director of the sports medicine center in the orthopedic surgery department of Hadassah University Medical Center in Jerusalem's Ein Kerem and head of sports medicine at Hadassah Optimal, replies: Patella femoral pain syndrome is characterized by pain around the kneecap. It might be that you suffer from that, but the problem could also be vascular (involving blood vessels in your legs) or involve another condition. I recommend that you consult a specialist (orthopedist and/or vascular expert) to diagnose it. If you do have patella femoral pain syndrome, then sitting for hours in a bus or plane certainly is uncomfortable. Physiotherapy can help, and getting up and walking around during a flight will certainly ease the discomfort. But first, the condition must be diagnosed. I am a 30-year-old man married for two years who works in hi-tech. My wife has not yet gotten pregnant. I use a laptop frequently for work when I am out of the office. Often, I have no easily available table and have to put the computer on my lap. I have heard that it could produce male fertility problems. Is it true? D.V., Hod Hasharon Judy Siegel-Itzkovich comments: Loyola University's Stritch School of Medicine has issued advice about this matter. Reproductive endocrinologist Dr. Suzanne Kavic notes that while fatherhood might be far from the minds of many young men, behavior patterns they establish early on may impact their ability to become a father later. Excessive laptop use tops this list of liabilities, she says, as the heat generated from laptops can impact sperm production and development, making it difficult to conceive. She recommends putting laptops on a table whenever possible, or even a cardboard file or other hard surface on your lap if there is no table, to prevent damaging sperm and decreasing counts and motility. Other tips to protect male fertility include avoiding hot tubs; wearing boxer-type underwear instead of tight briefs; engaging in sexual intercourse no more than every other day around the woman's ovulation; exercising moderately (one hour, three to five times per week); avoiding exercise such as bike riding that can generate heat or trauma to the genital area; eating well; getting eight nightly hours of sleep; drinking a lot of water and limiting caffeine to no more than two cups per day; not smoking; avoiding drugs and excessive alcohol use; minimizing exposure to toxins; avoiding excessive weight gain or weight loss; and practicing stress reduction techniques. Kavic adds that 40 percent of fertility problems are attributed to males. It is best for both of you consult a fertility specialist if you are concerned about it. Rx for Readers welcomes queries from readers about medical problems. Experts will answer those we find most interesting. Write Rx for Readers, The Jerusalem Post, POB 81, Jerusalem 91000, fax your question to Judy Siegel-Itzkovich at (02) 538-9527, or e-mail it to firstname.lastname@example.org, giving your initials, age and residence.