Kate Johnson of the Montreal Bureau contributed to this report.
MONTREAL — Three out of four commonly used vaginal lubricants caused significant decreases in sperm motility in a prospective, controlled study—and it appears that these and other lubricants can impact chromatin integrity as well, Ashok Agarwal, Ph.D., reported.
“Despite warnings by researchers, there is still great confusion among physicians and subfertile couples who are trying to conceive. These lubricants may impact the fertilization process and cause a failure of fertilization,” he said at the joint annual meeting of the American Society for Reproductive Medicine and the Canadian Fertility and Andrology Society.
Of the approximately 11 million couples in the United States who are trying to conceive—6 million of whom have been trying for more than 1 year—an estimated 75% experience an increased incidence of vaginal dryness, Dr. Agarwal told this newspaper, referring in part to data from the National Center for Health Statistics and the Centers for Disease Control and Prevention.
The researchers collected sperm either incubated at 37° C in human tubal fluid (HTF) media (the controls) or in 10% lubricant treatments made with the lubricant samples from normal donors and diluted these samples to 20–40 × 106/mL using HTF with 10% human serum albumin.
In one part of the study, sperm samples from 13 donors were either incubated at 37° C in HTF (the controls) or in 10% lubricant treatm es of culture, the mean percentage of progressively motile sperm differed significantly between the controls and three of the four lubricant groups.
Sperm exposed to FemGlide, for instance, were 22% less motile than sperm incubated in HTF.
There were even greater decreases in motility—an 89% decrease and a 60% decrease—in sperm exposed to Replens and Astroglide, respectively, compared with sperm in the control group, reported Dr. Agarwal, director of the Clinical Andrology Laboratory and Reproductive Research Center at the Cleveland Clinic.
In the second part of the study, sperm from 12 donors were processed in the same way and placed in either HTF or 10% KY Jelly, FemGlide, or Pre-Seed. The sperm were cultured for 4 hours to evaluate sperm chromatic integrity after longer exposure to lubricants. After culture, the spermatozoa were flash frozen and analyzed for the percent damaged chromatin using the percent DNA fragmentation index (DFI).
There was no significant difference in the percent damaged chromatin between the HTF control group and the Pre-Seed group. There was a 15% and a 10% increase in DFI after exposure to FemGlide and KY, respectively, compared with control.
“Sperm motility changes occur in a rather quick fashion, and DNA damage takes a little more time,” Dr. Agarwal told this newspaper. “We thought 4 hours [to evaluate DNA damage] is reflective of the real physiologic process.”
Because the lubricant Pre-Seed caused little difference in either sperm motility or chromatin integrity, compared with controls, “we can say that, from our study, this particular compound does appear to fare much better,” he said. “But there should be more studies done in other centers that involve larger numbers of patients.”
At this time, “physicians should just be aware that not every jelly and lubricant is equal. The idea that almost all lubricants not containing spermicides will not damage the sperm is a common misperception,” Dr. Agarwal said.
In fact, the loss of motility observed with three of the four lubricants studied “is similar [in magnitude] to the loss of motility found with contraceptive gels,” he said.
The study was conducted with all lubricants provided at no cost by INGfertility Inc., the manufacturer of Pre-Seed, Dr. Agarwal said. He reported no conflicts of interest.