This could explain sterility in some couples

May 9, 2008 18:06 GMT  ·  By

Do you want a kid? If your answer to this is in the positive, it's time you forgot about lubricants, at least about some of the commercially available ones. As signaled by a new research presented at the American College of Obstetricians and Gynecologists annual meeting, in New Orleans, some lubricants appear to paralyze sperm cells.

"Most commercial lubricants are toxic to sperm, and couples who want fertility should think about carefully choosing the lubricant they want," said co-author Dr William H. Kutteh, a reproductive endocrinologist at the University of Tennessee, in Memphis. The research team tested sperm exposed to four commercially available lubricants: K-Y Jelly, Replens, Touch and Astroglide, and ConceivEase, a new 'fertility-friendly' lubricant developed by the researchers themselves.

"The test results could be good news for couples having difficulty conceiving. People are afraid of going to a fertility doctor because they think they will have to spend so much on IVF [in vitro fertilization]. Sometimes all you need is an oil change. If sperm aren't moving properly, fertility is affected. The sperm have to move through the vagina, through the cervical mucus and out to the fallopian tube. Anything that decreases the motility of the sperm will make the pregnancy rate decline. Sperm can live for 48 to 72 hours," Kutteh explained.

Sperm cells coming from five subjects, who had initial sperm counts higher than 65% motility, were exposed to the 5 types of lubricants, and sperm motility was assessed at intervals of one minute, 15 minutes, 30 minutes and 60 minutes. The ConceivEase preserved sperm motility at 65%, but one hour later Touch decreased it to 10%, while the other three lubricants annulled sperm motility completely. The same team had observed the harmful effect the lubricants have on sperm over 10 years ago.

"Lubricant use during intercourse is common among couples undergoing fertility treatment partly because ovulation-inducing agents can cause vaginal dryness," said Kutteh.

ConceivEase comprises light mineral oil, Vitamin E, and glycerol; its growth medium pH (acidity) changes and other environmental variations impact negatively the sperm. However, the study "holds promise because it doesn't alter sperm motility at one hour. But, I'd like to see results beyond the one hour, up to 72 hours," said Dr Jennifer Wu, an obstetrician-gynecologist at Lenox Hill Hospital in New York City.

Even with these results, the researchers reinforce their warninf that lubricants cannot be used as contraceptives.