Lubricants and Fertility
Lubricants and fertility: Are some detrimental to sperm? by Dr. Bradley Miller of RMA of Michigan
For many couples throughout the United States, trying to conceive a baby can be extremely challenging. We know this comprises at least 15% of the reproductive-aged population, translating into millions of couples throughout the United States. Typically, couples will try to increase their chances of conception by undergoing timed intercourse. Timed intercourse itself can lead to many unintended complications. For example, there could be performance anxiety on the part of the male partner such as erectile dysfunction. On the other hand, female partners can also be affected by having vaginal dryness. It is reported that vaginal dryness is a very common problem and is faced by as many as 75% of the couples trying to conceive. It has also been shown that approximately 25% of these couples use over-the-counter lubricants to assist in having timed intercourse.
Unfortunately, many lubricants may in turn act as spermicides even if they are “safe for human use.” In order for sperm to survive, they have to transition from the seminal fluid into the cervical mucus where they are in a protected environment. This environment is typically an alkaline one, meaning that the pH level is between is 7.0 and 8.5. The normal vaginal fluid, as well as lubricants, can be highly acidic, therefore, having low pH values and being detrimental to sperm function. All lubricants, even water-based ones contain chemicals that can change the osmolarity of the environment thus causing the sperm cells to either swell or shrink, either killing them or impairing their motility. Even saliva can contain digestive enzymes that affect sperm viability. Finally, plain tap water can be just as spermicidal to those couples trying to conceive.
Back in 1994, we published one of the first in vivo, meaning within the body, studies looking at the effect of vaginal lubricants on sperm motility. Our study showed that there was severe impairment to sperm penetration of cervical mucus by a standard over-the-counter lubricant, although the concentrations of the intravaginal lubrication were not measured and did vary from woman to woman. Our postcoital (after intercourse) examination in the cycles where the couples did use the lubricant revealed that there were significantly fewer motile and immotile sperm seen within the cervical mucus.
A study performed in 1998 by Anderson showed that lubricants also had a detrimental effect on sperm motility. They compared KY Jelly ®, baby oil, olive oil, and saliva on sperm motility in 16 samples from couples undergoing infertility treatment. They found that all lubricants, except for the baby oil, significantly decrease the percentage of motile sperm and even at lower concentrations of only 6%, both olive oil and saliva still significantly reduced motile sperm while KY Jelly diminished head movement of the sperm. Therefore, they concluded that even at very low concentrations, lubricants impair sperm motility and thus may negatively affect fertility.
A more recent study, published in 2008 by Agarwal, is a perspective study comparing 13 patients using normal sperm donors. They investigated over-the-counter vaginal lubricants: Pre-Seed®, FemGlide®, Astroglide®, and Replens®, effects on sperm motility. They noted that the percent of motile sperm was not negatively affected by Pre-Seed whereas FemGlide, Replens, and Astroglide lubricants demonstrated a dramatic decrease in sperm motility. Therefore, they concluded that Pre-Seed did not cause a significant decrease in progressive motile sperm in comparison to the other lubricants. Pre-Seed is a hydroxyethylcellulose-based lubricant and has had no demonstrable adverse effect on the sperm parameters in previous studies.
The American Society of Reproductive Medicine (ASRM), our professional society, recommends commercially available water-based lubricants such as Astroglide, KY Jelly, and Touch® be avoided as they showed that they inhibited sperm motility in laboratory studies by 60% to 100% within 16 minutes of incubation. Canola oil had no detrimental effect on sperm motility. They also report that KY Jelly, olive oil, and saliva, even in diluted concentrations as low as 6.25%, had a negative impact on sperm motility and velocity whereas mineral oil had no impact. Therefore, they recommend using mineral oil, canola oil, or hydroxyethylcellulose-based lubricant if vaginal lubrication is required.
Interestingly, an abstract that was presented at the ASRM meeting in October of 2009 studied the impact of vaginal lubricants on couples actually trying to conceive. They looked at women between the ages of 30 and 45 with no history of infertility or having tried to conceive for less than three months. They looked at 125 participants with a total of 423 menstrual cycles. While trying to conceive, 25.6% of the women reported using lubricants. Of those, 50% used KY brand while 21% used Astroglide, 12.5% used Pre-Seed, 6% used Silk®,, and 12.5% used some other brand. The pregnancy rate per month in those couples using lubricants was 17.5% while those not using lubricants had a pregnancy rate of only 15.6%. This is not statistically significant, but it certainly showed that there was no impaired effect from using lubricant. The average time to pregnancy for lubricant users was just 3.3 cycles compared to 4.2 cycles in the non-users. So, they concluded that lubricant did not appear to significant impact the pregnancy rate in those couples trying natural conception.
In summary, my recommendations are to avoid most over-the-counter vaginal lubricants with the exception of Pre-Seed or those containing hydroxyethylcellulose-based lubricants. Other options would be mineral oil or canola oil as opposed to purchasing a name brand vaginal lubricant. Good luck and I hope that this information was useful to you!
Bradley Miller, M.D.
Reproductive Medicine Associates of Michigan