Human reproductive fluids and vaginal pH

A human sperm fertilizing an egg

The Photo: A scanning microscope image of a human sperm fertilizing an egg. No form of birth control (except abstinence) is 100% effective so a girl’s worst fear can be realized when a pregnancy is unplanned regardless of why it occurred; from an unprotected casual encounter or from a contraceptive failure. It’s what responsible sexually active women try our best to avoid and what correct use of effective contraceptive methods is all about. Fortunately women facing an unplanned pregnancy now have several options.

pH (potential of hydrogen): The term pH refers to a numerical measure of the acidity or alkalinity of any solution. pH values typically vary across a scale from 0 to 14, with the pH of neutral solutions equal to 7, increasing values have increasing alkalinity and decreasing values have increasing acidity. The pH of the vagina corresponds to the secretions continually produced in conjunction with the vaginal flora.

Normal vaginal pH: pH refers to the vagina’s acidity level. A vaginal pH of 3.8 - 4.5 (slightly acidic) indicates that there is a perfect amount of good bacteria (lactobacilli), and no overgrowth of the bad bacteria that can cause odor, irritation and sometimes infection.  A home vaginal pH test kit measures pH on a scale of 1 to 14. Abnormal vaginal pH may be higher or lower than normal vaginal pH. High vaginal pH numbers indicate less acidity, while lower than normal vaginal pH levels indicate high acidity. Abnormal vaginal pH frequently indicates the presence of a vaginal infection. However, not all vaginal infections cause changes to vaginal pH. This means that having a normal vaginal pH test does not mean that you do not have a vaginal infection.

If the vaginal pH is above normal, the most likely reason is that the woman has bacterial vaginosis (BV) and not a yeast infection. In this case, don't use OTC medications for vaginal yeast infections because the medication does not treat BV. You’ll need to see your doctor for diagnosis and treatment.

On the other hand, if the vaginal pH is normal or below normal and she has had previous vaginal yeast infection diagnosed by a doctor, she could try one of the OTC medications for vaginal yeast infections. If the OTC medication for vaginal yeast infection does not cure the vaginal symptoms or infection, see your doctor for diagnosis and treatment.

 So, what makes pH rise higher than 4.5? There are a surprising number of triggers that can upset the vaginal ecosystem:

• Menstruation: Blood has a pH of 7.4, so during your period, vaginal pH becomes elevated.
• Tampons: Since they retain the fluids that cause pH to increase, tampons can contribute to the problem, especially if you “forget” a tampon and leave it in too long.  
• Intercourse: The pH of semen is 7.1 to 8, slightly alkaline.
• Douching and cleansers: Any vaginal infusion of water or other fluids can affect vaginal pH. The pH of water is 7, and fragrances and perfumes can also irritate the vagina.
• Menopause or pregnancy: These are times where hormones fluctuate, which is associated with elevated pH.
• FCM; Fertile cervical mucus: In normal conditions, fertile cervical mucus has a pH level of 6.5 to 8.5 and should be able to stretch 10cm in either direction. FCM will temporarily decrease the acidity of the vagina to help sperm survive the acidity of the vagina during a woman’s fertile interval.

Semen: A viscous whitish secretion of the male reproductive organs, containing spermatozoa and consisting of secretions of the testes, seminal vesicles, prostate, and bulbourethral glands. It’s also called seminal fluid. The pH of semen is 7.1 to 8, slightly alkaline. 

The average sperm count today is between 20 and 40 million per milliliter in the Western world, having decreased by 1-2% per year, from a substantially higher number, decades ago.

Total sperm count, or total sperm number, is the total number of spermatozoa in the entire ejaculate. By WHO, lower reference limit (2.5th percentile) is 39 million per ejaculate. The median ejaculation (50th percentile) contained 255 million sperm.

Sperm motility: A more specified measure is motility grade, where the motility of sperm is divided into four different grades:

• Grade a: Sperm with progressive motility. These are the strongest and swim fast in a straight line. Sometimes it is also denoted motility IV.
• Grade b: (non-linear motility): These also move forward but tend to travel in a curved or crooked motion. Sometimes also denoted motility III.
• Grade c: These have non-progressive motility because they do not move forward despite the fact that they move their tails. Sometimes also denoted motility II.
• Grade d: These are immotile and fail to move at all. Sometimes also denoted motility I.

Volume: WebMD advises that semen volumes between 1.0 mL and 6.5 mL are normal; WHO regards 1.5 ml as the lower reference limit. Low volume may indicate partial or complete blockage of the seminal vesicles, or that the man was born without seminal vesicles. In clinical practice, a volume of less than 2 mL in the setting of infertility and absent sperm should prompt an evaluation for obstructive azoospermia. A caveat to this is to be sure it has been at least 48 hours since the last ejaculation to time of sample collection.

Semen pH: WebMD lists a normal semen pH range of 7.1-8.0; WHO criteria specify normal as 7.2-7.8 Acidic ejaculate (lower pH value) may indicate one or both of the seminal vesicles are blocked. A basic ejaculate (higher pH value) may indicate an infection. A pH value outside of the normal range is harmful to sperm.

Liquefaction: Liquefaction is the process when the gel formed by proteins from the seminal vesicles is broken up and the semen becomes more liquid. It normally takes less than 20 minutes for the sample to change from a thick gel into a liquid. A liquefaction time within 60 minutes is regarded as within normal ranges.

Spermicides: In order to make barrier contraceptives more effective there are formulations of chemical, Nonoxynol-9 (N-9) and lactic or citric acid mixed with a gel carrier that provides an acidic pH to immobilize sperm should a condom break or a diaphragm leak or become displaced. ContraGel (advertised by its maker not as a spermicide, but as a barrier method when used with a cervical barrier) uses a base of lactic acid with a pH of 3.8 which is hostile to the sperm.

For dive-sex we use a private label product called DiveGel+ (in 10 ml prefilled disposable applicators) which is a specially formulated silicone gel that won’t degrade silicone cervical barriers fortified with a pH balanced biocide and FloraFix a type of Lactobacillus with a pH of 3.8 that helps maintain the acidity of the vagina regardless of how many unprotected men a girl is penetrated by per day. For non-diving encounters the formulation is being rebranded as ‘FloraFix’ and packaged in 5ml disposable applicators and is being used very successfully by our escorts.

My cervical barriers: I dislike using condoms unless the man has an unknown sexual history. I love the skin-on-skin contact which Oves permits me and the feel of a man’s liquefied fluids draining out of me after he has done his biological best to impregnate me. While the rest of my circle is all fitted with copper IUDs I still prefer to use an Oves cervical cap or a diaphragm.  I stocked up on Oves before they went out of business and use them each for multiple cycles, so if I don’t get preggers or have a change to the surface of my cervix I should have enough to last me until menopause. At 42 my fertility is declining, but I still have regular cycles and love how well both Oves and my diaphragm (depending where I am in my cycle) are protecting me.