Do Personal Lubricants Like KY Jelly and Replens Kill Sperm?

Why Some Personal Lubricants Are Not Fertility Friendly

Young couple being affectionate
If you need to use a personal lubricant when trying to conceive, be sure to avoid KJ Jelly and others that are not fertility friendly. ImagesBazaar / Getty Images

Can lubricants like KY Jelly kill sperm? Sort of. They certainly can't be considered sperm friendly.

While you can't use them to prevent pregnancy (you'd need spermicide for that), they are not a good choice when you're trying to get pregnant.

The effect lubricants may have on fertility is especially relevant to couples trying to conceive. Difficulty with vaginal dryness is twice as common in trying to conceive couples than in the general population.

Also, problems vaginal dryness tend to increase the longer a couple is seeking to get pregnant.

According to a 2003 study, one in four couples reported using personal lubricants (that were not fertility friendly) while trying to conceive. With the increase in fertility friendly lubricants on the market, it’s likely that more people are now aware that they should not be using non-sperm friendly lubes.

However, if you’re one of those who didn’t know, you’re far from alone.

What’s the problem with regular lubricants? And how might they impact sperm?

How Regular Personal Lubricants Impact Sperm

Several studies have looked at the effect various lubricants have on sperm.

Researchers have investigated…

  • how well the sperm swim (motility) after exposure to the lubricant
  • whether or not DNA damage occurred
  • whether sperm were still alive

One study compared sperm motility after exposure to Pre-Seed (a fertility friendly lubricant), Astroglide (the non-TTC version), KY Warming, KY Sensitive, KY Tingling, baby oil, canola oil, sesame oil, and mustard oil.

From previous research, we know that sperm make the transition from the semen and into cervical mucus about 1.5 minutes after intercourse. The majority of healthy sperm will make it into the cervical mucus within 15 to 20 minutes.

Therefore, researchers looked to see what percentage of sperm were moving after 0 minutes, 5 minutes, 30 minutes, and 60 minutes of exposure to a 10% solution of the various lubricants.

This is what they found:

  • Pre-Seed was the least harmful to sperm, with only a small (but still significant) decrease in sperm movement.
  • KY lubricants were the most harmful to sperm movement, with KY Tingling reducing sperm movement to almost nothing after 60 minutes.
  • Astroglide was also significantly harmful to sperm movement. After 60 minutes, under 60% were moving. (Compare that to Pre-Seed, where just under 80% were still moving after an hour.) 
  • Of the oils, mustard oil was the best for sperm motility. In fact, there was no decrease in sperm motility at all.
  • Baby oil was more sperm friendly than Astroglide, but not as sperm friendly as Pre-Seed.
  • Sesame oil was the worst of the oils, with results similar to Astroglide, but still better than KY. 

A separate study compared the lubricants Pre-Seed, FemGlide, Replens, and Astroglide to a control substance.

Compared to the control, they found that sperm motility decreased...

  • by 3% with Pre-Seed
  • by 22% with FemGlide
  • by 60% with Replens
  • and by 89% with Astroglide

[Note: It's important to recognize the Astroglide tested was not their fertility friendly version.]

While there are many lubricants that advertise they are sperm friendly, there is little independent research on how they perform.

One study looked compared various lubricants, including some marketed as fertility friendly. They found that…

  • Sperm exposed to Pre-Seed had the best vitality (live sperm) numbers, with 92% still alive after two hours of exposure.
  • ConceivePlus was close behind, with just over 70% still alive two hours after collection.
  • Both Pre-Seed and Conceive Plus left more sperm alive after two hours compared to the lab control.
  • MaybeBaby, a supposed fertility friendly lubricant, left only 50% of the sperm alive.
  • ForeLife, another “sperm friendly” lube, performed the worst, with only 27% vitality after two hours.

    Some studies have also found DNA damage after exposure to some lubricants, though other studies have not found damage.

    Sperm Friendly Lubricants

    There are lubricants that have been made to be fertility friendly. The most popular sperm friendly lubricants are PreSeed and ConceivePlus.

    It may be possible to use raw egg whites as a personal lubricant, and some people do it. The idea is that it would be closest to nature's fertility friendly lubricant, egg white cervical mucus.

    However, there is a risk of allergic reaction (if you have an allergy to eggs) and possible salmonella poisoning. Plus, it's kind of messy.

    Canola oil and plain baby oil are somewhat sperm friendly options. But they may lead to vaginal infection or irritation.

    Saliva is not a sperm friendly option. The acidity is harmful to sperm.

    The Bottom Line on Lubricants When Trying to Get Pregnant

    Unless a lubricant has been specifically made for trying to conceive, you should be wary.

    Both water- and oil-based lubricants have been found to interfere with sperm movement, and some kill or alter the DNA of sperm.

    It's also important to mention that a lack of arousal fluids or cervical mucus may indicate a fertility problem.

    If this is a common problem for you, and you have not mentioned it to your doctor, be sure to speak up. It may help your doctor treat your infertility.

    More on sex and fertility:


    Ellington, J. et al. “Prevalence of Vaginal Dryness in Trying-to-Conceive Couples.Fertility and Sterility, Volume 79 , 21 – 22.

    Mowat A1, Newton C, Boothroyd C, Demmers K, Fleming S. “The Effects of Vaginal Lubricants on Sperm Function: an In Vitro Analysis.J Assist Reprod Genet. 2014 Mar;31(3):333-9. doi: 10.1007/s10815-013-0168-x. Epub 2014 Jan 5.

    Sandhu RS1, Wong TH1, Kling CA1, Chohan KR2. “In Vitro Effects of Coital Lubricants and Synthetic and Natural Oils on Sperm Motility.Fertil Steril. 2014 Apr;101(4):941-4. doi: 10.1016/j.fertnstert.2013.12.024. Epub 2014 Jan 23.

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