If you and your partner are trying to conceive, you may want him to check the label on his sunscreen.
man applying sunscreen
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If you and your partner are trying to have a baby, you may want to check the label on your sunblock. Because according to a new Danish study, the UV-filtering chemicals commonly used in sunscreen may be screwing with your man's fertility.

While the purpose of chemical UV filters is to reduce the amount of the sun's rays getting through your skin by absorbing UV, some of the filters are absorbed through the skin when you rub on the lotion. In fact, UV filter chemicals have reportedly been found in 95 percent of urine samples in the U.S.

Researchers tested 29 of the 31 UV filters allowed in sunscreens in the U.S. and Europe on healthy human sperm cells from fresh semen samples obtained from several healthy donors. They found that 13, or almost half, of the filters tested induced calcium ion influxes in the sperm cells, which can stop them from effectively fertilizing an egg.

And of those 13 UV filters, nine of them mimicked the effect of progesterone, which stops sperm cells functioning normally. "This effect began at very low doses of the chemicals, below the levels of some UV filters found in people after whole-body application of sunscreens," said the study's senior investigator Niels Skakkebaek, M.D. "These results are of concern and might explain in part why unexplained infertility is so prevalent."

Dr. Skakkebaek is now calling for clinical studies to investigate whether chemical UV filters affect human fertility. "Our study suggests that regulatory agencies should have a closer look at the effects of UV filters on fertility before approval," he said.

In the meantime, you may want to steer clear of these eight UV filters approved for use in the U.S in sunscreen and in sunscreen-containing products like makeup, moisturizers, and lip balms:

  • avobenzone
  • homosalate
  • meradimate
  • octisalate (also known as octyl salicylate)
  • octinoxate (or octyl methoxycinnamate)
  • octocrylene
  • oxybenzone (also called benzophenone-3 or BP-3)
  • padimate O

Hollee Actman Becker is a freelance writer, blogger, and a mom. Check out her website holleeactmanbecker.com for more, and follow her on Twitter at @holleewoodworld.