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INTRODUCUONLindsay and Medes showed in 1926 that a diet deficient in ascorbic acid (AA) for one month caused a massive degeneration of the germinal epithelium with desquamation into the lumina of the tubules in the testes of guinea pigs.' In 1941, it was reported that the seminal plasma of normal man contains 12.8 2 1.6 mg/dl of AA, which is actively concentrated and secreted by the seminal vesicles during ejaculation.24 This level is many times the 0.2-1.40 mg/dl level normally found in serum, and suggests a vital metabolic role for AA in the seminal plasma. In 1960, Lindahl and Kihlstrom described a proteinaceous substance in seminal plasma, which appears in two forms (oxidized or reduced), and which is reversibly transformed from one form to the other.5 The reduced form has antiagglutinic activity-that is, it prevents clumping and immotility of sperm in seminal plasma. This form is attached to the surface of the sperm and loses its ability to be fixed to the cell surface when oxidized. Ascorbic acid, a biological reducing agent, has been shown to reduce the oxidized protein in several in vitro studies6 In 1986, the studies of Lindsay and Medes were duplicated when male guinea pigs with proven fertility were placed on an avitaminotic C diet for 3 weeks and sacrificed. The most severe histological damage was observed in the testicular tissue. The most pronounced damage was in the cauda epididymus, wherein sperm undergo maturation, with thickened peritubular muscle layer and connective tissue, decreased tubular diameter and epithelial cell height, and nuclear pycnosis. Similarly affected was the vas deferens and accessory sex glands, although to a lesser degree. Sperm analysis of semen samples collected from testis, cauda epididymus, and vas deferens showed decline in total sperm count and sperm motility, as well as an increase in the number of abnormal sperm.'Over a decade ago, the obstetricians of our clinical service commenced prescribing AA to husbands when it was apparent from fertility testing of both husband and wife that infertility was possibly due to sperm agglutination in excess of 25%. The practice is to prescribe 1 g per day for 10 days and then 500 mg per day through two menstrual cycles (60 days). This practice has proved successful. Subsequently, we reported a comparison of the differences in sperm qualities between a group of 20 men with sperm agglutination over 25% who followed the AA supplementation protocol and 312

Daily supplementation with 1000 mg of ascorbic acid results in a significant decrease of blood-lead levels associated with the general population. Ascorbic acid supplementation may provide an economical and convenient method of reducing blood-lead levels, possibly by reducing the intestinal absorption of lead.

Studies of maternal amniotic fluid and serum at delivery have revealed the presence of toxic metals or deficiencies of essential metals associated with high-risk pregnancy. Essential and toxic metal levels were studied in 29 preeclamptic and 101 normal pregnancies. The authors grouped the samples according to the following gestation ages: 33-36 wk (48 normal and 10 preeclamptic) and 37-40 wk (53 normal and 19 preeclamptic). The metals studied were calcium, magnesium, zinc, selenium, copper, cadmium, and lead. Comparisons of the 33-36-wk gestation group showed significant differences between normal and preeclamptic amniotic fluid in levels of lead, calcium, magnesium, zinc, and selenium. There were also significant differences in levels of magnesium, copper, zinc, cadmium, and lead during the gestation period of 37-40 wk. The changes observed in calcium and lead levels were consistent with the results of animal studies in which investigators have found depressed calcium transport associated with subacute or chronic lead poisoning, resulting in a physical syndrome similar to preeclampsia.

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