However, for those who want to take the rise but are having trouble conceiving, a Louisana doctor reports that surgery with a laser beam on women with diseased fallopian tubes is greatly increasing their chances of becoming pregnant. Diseased or blocked fallopian tubes can prevent movement of a woman's eggs from ovary to uterus, making her infertile. The new microsurgical procedure, pioneered by Dr. Joseph H. Bellina of the Louisiana State University School of Medicine, uses a laser "knife" that vaporizes tissue. The hot laser beam is used to cut out the diseased end of the fallipian tube as in conventional surgery using a scalped. But then, unlike standard techniques, the laser is used to drill a hole through the wall of the uterus. The surgeon then inplants the disease-free section of the tube into the uterus without disturbing the lining of the channel through which the egg and sperm unite. Dr. Bellina estimates that 400,000 American women between the age of 18 and 30 have disease in these tubes running from the ovaries to the uterus. One of five such cases is caused by gonorrhea. Bellina said 85 percent of 83 women treated last year were given by their referring doctors only a 5 percent chance of becoming fertile following conventional surgery. Of 44 women ready to attempt conception after undergoing laser surgery, half become pregnant within three months.