The women participants ranged from 18 to 44 years of age, and the men were over 18. None had a medical diagnosis of infertility.

Their findings suggested that some, but not all, UV filters may be associated with diminished fertility in men, independent of their partners' exposure.

The researchers observed effects among men with the highest exposure to UV filters BP-2 or 4OH-BP.

"In our study, male fecundity seems to be more susceptible to these chemicals than female fecundity. The women participants actually had greater exposure to the UV filters overall, but their exposure wasn't associated with any significant pregnancy delays," study author Germaine Louis of the National Institute of Child Health and Human Development, part of the NIH, said in a statement.

Louis said people are still encouraged to continue using sunscreen to avoid skin cancer but men who are concerned about fertility may try other ways to reduce their exposure to benzophenone UV filters, such as washing after returning indoors.

The researchers cautioned that the results are preliminary and that additional studies are needed to confirm their findings.