table of contents
- In a nutshell
- What’s “fertility-friendly” lube, anyway?
- The lube ingredients and characteristics to look out for
- Let’s dive into the science!
- Okay, so how do different lubes affect actual real-world pregnancy outcomes?
- Why do lab-based studies on lube and sperm differ from real-world outcomes on pregnancy rates?
- Is “fertility-friendly” the way to go?
- Annnnnd just for fun: When in Rome… don’t lube as the Romans did
If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.
In the US, about 66% of people with ovaries say they’ve used lube at some point. Beyond being a great way to spice things up in the bedroom, lube can help ease vaginal discomfort experienced during sex (something experienced by 42% of pre-menopausal people in general, and twice as many people who are actively trying to conceive).
Over the past few years, the lube world has gotten a bit of a shake-up after the FDA created a specific category for “fertility-friendly” or “sperm-friendly” lube. Technically, the category is called “gamete, fertilization, and embryo compatible personal lubricants,” (kiiiind of a mouthful, we know).
In this post, we’ll cover the science behind what it means to be classified as a “fertility-friendly lube,” how that compares to other types of lube, what ingredients and properties you should know about, and which claims are worth some healthy skepticism.
Mega spoiler alert: No lubes currently on the market will increase your chances of getting pregnant, but some lubes create a more conducive environment for sperm to swim around in.
In a nutshell
The main takeaway from all of our research? Based on FDA categorizations and lab data, we do recommend using a “fertility-friendly” lube if you’re trying to get pregnant — ideally one with a pH of 7.0 that’s also paraben-free, glycerin-free, and iso-osmotic.
Here are the main points we’ll cover in the article:
- The FDA has three groups of lubricants, and only one is considered “fertility-friendly.” Products get this label if extensive testing shows no negative impact to sperm, eggs, and fertilization.
- “Fertility-friendly” lubes often market themselves as “sperm-friendly” because they’re demonstrably less toxic to sperm. That said, “fertility-friendly” lubes don’t seem to increase your chances of getting pregnant relative to no lube use, or relative to using lubes that don’t have the “fertility-friendly” designation.
- If you’re trying to get pregnant, pay close attention to your lube’s pH and osmolality levels and stay away from parabens and glycerin — these ingredients are not great for your reproductive health.
What’s “fertility-friendly” lube, anyway?
The FDA considers lube a medical device and created two specific categories of personal-use lubricants, each requiring different standards of scientific testing and monitoring.
“Fertility-friendly” lubricants, also known as “gamete, fertilization, and embryo compatible” personal lubricants
The FDA introduced this category of lube in 2017, setting industry standards for which products can call themselves “fertility-friendly.” Since this is a relatively new category, it only recently started becoming more popular.
Products with this seal of approval have been extensively tested and demonstrated no detrimental effects on sperm, eggs, and fertilization. Testing is done both in-vitro (e.g., sperm are taken and exposed to lube in the lab, with effects on sperm survival and motility measured) and in-vivo (e.g., the lube is tested in animals like rabbits and mice, and effects on fertility and embryo development are measured). Testing for endotoxins (i.e., harmful substances that are released when cells die) is also done, as even low levels of these may have negative effects on sperm and embryos.
As of February 2021, there are five lubes you can buy in the US that have been approved as “fertility-friendly” by the FDA (excluding discontinued options):
- Conceive Plus
- BioGenesis by Good Clean Love
- JO Actively Trying
The difference between “fertility-friendly” lube and personal lube
All lubricants are made to be used during sexual activity and with potentially sensitive areas. Because of this, there’s some monitoring of safety and side effects, both before and after they get approved. For example, some (but not all) brands run tests for condom compatibility.
An important distinction between personal lubricants and “fertility-friendly” lubricants, though, is that personal lubricants have not explicitly provided the FDA with data on their effects on sperm, eggs, and fertilization, while “fertility-friendly” lubes have. It’s possible that personal lubricants have no effects on sperm, eggs, and fertilization, or it’s possible they have a large effect; we just don’t know because this data isn’t required for lubes in this FDA category.
Some of these lubes do contain ingredients that have been linked to negative health and fertility outcomes (parabens, we’re looking at you) — but note that the studies here have focused on ingredients alone and not the lubricants as a whole. More on this in the next section.
The lube ingredients and characteristics to look out for
Even though all “fertility-friendly” lubes are unified in their lack of impact to sperm, eggs, and fertilization, there isn’t any one magic ingredient that makes a lube “fertility-friendly,” and there is a good bit of variability in ingredients and characteristics of lubes in this category.
Below, we’ll detail the ingredients and characteristics to look for and what you might want to avoid — some of which are important for sperm health and survival, and some important for general vaginal health. (If you want to go deeper, here’s a peer-reviewed article on ingredients that might have effects on eggs, the vagina, or sperm.)
1. pH level around 7: Though “normal” vaginal pH is in the 4.0-4.5 range, this changes slightly across the menstrual cycle and during sexual arousal. Vaginal pH during sexual arousal, semen, and cervical mucus around ovulation have pH levels close to 7.0. These are good things for lube users who are trying to get pregnant because sperm are happiest (aka most viable) when pH is around 7.0; lower pHs are associated with a reduction in sperm survival.
Our rec here? Stick to lubes that explicitly state they have a pH around 7.
2. Iso-osmotic: Osmolality (say that five times fast) refers to the number of particles per unit of water. The vagina has a natural osmolality, and if this differs too much from the lube you’re using, it may lead to vaginal cell death or a greater risk of vaginal infections. Look for products that are iso-osmotic (i.e., have an osmolality similar to a vagina). For context, “normal” vaginal osmolality is in the 270 mOsm/Kg range, and several widely used vaginal lubricants have osmolality values 4 to 30 times as high.
To see how your lube stacks up in terms of its osmolality, you can check out this helpful resource from the World Health Organization. Because osmolality can only be calculated for water-based lubes (after all, you can’t calculate the number of particles per unit of water if the lube doesn’t have water in it!), that list won’t include values for things like natural oils.
3. Paraben-free: Parabens are compounds that often go under the name butylparaben, methylparaben, or propylparaben — and they’re found in tons of beauty products, food products, and in some lubes. They’re part of a class of compounds called endocrine-disrupting chemicals (EDCs) because they bind to hormone receptors and affect your hormones.
4. Glycerin-free: Glycerin (also sometimes called glycerine and glycerol) is a natural, plant-based compound that often makes the osmolality of lubes too high. Based on research, experts believe that it can significantly decrease sperm motility. Plus, since it’s broken down into sugar, it can also feed harmful microbes and lead to things like yeast infections.
Let’s compare “fertility-friendly” lubes on the market
Even given all of the above information, some “fertility-friendly” lubes still have ingredients like parabens and glycerin — likely because the approved “fertility-friendly” lubes that do have these ingredients were not found to have significant impacts on sperm and egg health in the lab (confusing, we know!).
From what we were able to find, here are how the “fertility-friendly” lubes currently on the market stack up in terms of the above criteria. There are two that check all the boxes (yay for options!):
|pH around 7||Paraben-free||Glycerin-free||Iso-osmotic|
|BioGenesis by Good Clean Love||✅||✅||✅||✅|
|JO Actively Trying||✅||❌||❌||✅|
Let’s dive into the science! Here’s what lab studies say about how different types of lube impact sperm health
Manufacturers of different lubes as well as scientists in academic settings have been hard at work conducting experiments to determine exactly how different lubes on the market might impact sperm. Research has largely focused on their effects on sperm because lube likely doesn’t make it all the way to the egg, and testing hasn’t found significant effects of different types on eggs and embryos.
There are many studies of the effects of different lubes on sperm, though there is no single published study that head-to-head compares the five “fertility-friendly” lubes on the market right now (believe us, that study is high on our science wishlist).
Given that caveat, we’ll highlight one of our favorite studies on the effects of lube on sperm, conducted by a group of Australian researchers in 2014. They used sperm samples from 10 different people (some other studies use sperm from just one person!), tested eleven different commonly used lubes (though, only two of the “fertility-friendly” lubes currently on the market: Pre-Seed and Conceive Plus), and measured multiple important aspects of sperm function. Specifically, they looked at how different lubes affected:
- Sperm motility (how speedy those swimmers were). While sperm motility was considered “good” for 8 out of the 11 of the lubes examined, it was highest in a lube that has been FDA-approved as “fertility-friendly.”
- Sperm vitality (how many cells remained alive after lube exposure). The two lubes with the highest vitality measures (90% and 70%) were also FDA-approved as “fertility-friendly,” whereas the vitality rates in the other lubes ranged from 27% (yikes!) to 65%.
- DNA fragmentation (DNA damage). All lubes had similar effects on rates of DNA damage.
The authors of this study ended up giving three of the substances examined a rating of “sperm-friendly.” Those three? Pre-Seed, Conceive Plus, and a culture oil used in the context of assisted reproductive technologies (i.e., not a lube you can get your hands on in stores).
Importantly, several lubes that made explicit marketing claims about being “sperm-friendly” didn’t make this list. Because BabyDance, Biogenesis by Good Clean Love, and JO Actively Trying lubes were not included in the study, we can’t say how they would have stacked up in terms of their effects on sperm health.
Okay, so how do different lubes affect actual real-world pregnancy outcomes?
Because of the different effects of lubes on sperm movement and survival, you’d think that using certain lubes should be associated with better or worse outcomes in terms of getting pregnant. Oh, how we wish science would be that predictable.
In one study, 6,400+ women in North America and Denmark who were trying to conceive were asked if they used lube and whether their lube was water/oil/silicone-based or pH-balanced (not if it was on the FDA-approved list), and followed them for up to 12 months. There was no difference in people’s likelihood of getting pregnant based on their lube use (or lack thereof). Women who used what the researchers defined as “fertility-friendly” lube didn’t get pregnant more quickly or at higher rates than women who didn’t use lube at all, nor did women who used purportedly “sperm-unfriendly” lube get pregnant at lower rates than any other group.
A second study of roughly 300 women came to similar conclusions, when comparing pregnancy rates in women who used any sort of lube during the fertile window to women who did not. Here, too, there was no evidence to suggest differences in pregnancy rates between women who did and didn’t use lube.
Our takeaways here: The data suggests that lube use doesn’t impact real-world pregnancy outcomes, but we’re hesitant to get behind that claim 100% based on just those two studies. Neither study was controlled for all the things that can impact conception (e.g., timing of sex, nutrition, health conditions, and environmental exposures), nor did researchers assign couples to different lube use groups or look at whether lube might have different effects for different groups based on fertility-related variables. We’ll be keeping our eyes peeled for newer, methodologically stronger studies linking lube and conception and we’ll update you when we find them.
Why do lab-based studies on lube and sperm differ from real-world outcomes on pregnancy rates?
It’s confusing that lab-based studies show damaging effects of some lubes on sperm, but the use of these lubes in the real world don’t seem to affect your chances of conception.
Experts have come up with three main explanations that may be at the root of these differences:
- It’s possible that when used, lube stays on the external genitals and lower vagina, but doesn’t make its way far up enough to where sperm are released — meaning the sperm wouldn’t actually come into contact with any potentially damaging substances.
- Sperm are pretty darn speedy. By some estimates, they get from the upper vaginal tract and past the cervix in about a minute. This means the exposure time to damaging substances IRL is really short in comparison to exposure time in lab-based studies, most of which expose sperm to those substances for up to five minutes (some will even do a 24-hour exposure time!).
- Some lubes may have a negative effect on sperm, but perhaps using those lubes encourages couples to have sex more often. The result? A “breaking even” of sorts when it comes to your chances of conceiving.
Is “fertility-friendly” the way to go?
Because the perfect study on real-world lube use and pregnancy outcomes hasn’t been done yet, we can’t say for sure that using “fertility-friendly” lubes boosts your odds of getting pregnant. We also can’t say that using other lubes without the “fertility-friendly” designation decreases those odds.
What we can say is that there are demonstrable negative effects of some lubricants to sperm in lab-based studies, and that these effects were notable enough for the FDA to create a whole category for conception-friendly lubes. These two things, plus the fact that the perfect clinical study of lube use and conception rates hasn’t been conducted yet, lead us to favor “fertility-friendly” lubes as there’s no real downside to being vigilant about what goes in your body.
Bottom line? We recommend using a “fertility-friendly” lube — ideally one with a pH of 7.0 that’s also paraben-free, glycerin-free, and iso-osmotic.
If you’ve made it this far in the article and you still aren’t convinced that “fertility-friendly” makes enough of a difference to be worth it, that’s okay, too. The most important thing is that you have the information you need to make the decision that’s right for you.
Annnnnd just for fun: When in Rome… don’t lube as the Romans did
We dug up some pretty interesting facts while researching lube. The documented history of lube use goes waaaay back to around 350 BCE, where the Greeks allude to using olive oil as a contraceptive (disclaimer: Do not use olive oil as a contraceptive), perhaps first in a book written by the Greek philosopher Aristotle. More explicit (no pun intended) mentions of olive oil being used during sexual activity as a lubricant appear slightly later on in Roman novels from the 1st century, wherein authors describe it being used as a lubricant for leather dildos (you read that right — dildos have been around forever, too!).