General information about this test:
The NADAL® pH-Test is for measuring the pH value of vaginal fluid. The vaginal pH value is a useful screening parameter for disturbances of the vaginal microflora. Abnormal pH values are frequently an indicator for clinical or sub-clinical vaginal infections.
Application of the NADAL® pH-Test is intended for the following uses:

• For diagnosis of vaginal infections or the identification of conditions that are supportive for the manifestation of vaginal infections in premenopausal women (pregnant and non-pregnant)

• For reduction of the risk of premature birth and early diagnosis and treatment of vaginal infections by regular screening of the vaginal pH in pregnant women.

Reagents and material supplied:

• 50 hygienically packaged NADAL® pH-Test applicators for the measurement of vaginal pH

• 1 package insert

• 1 pH color scale for reading the result

Performance characteristics:
The measurement range of the NADAL® pH test is between 4.0 and 7.0. Best resolution is found for the clinically important range between pH 4.4 and 5.5. Values below pH 4.0 will be display as 4.0 and values higher than 7.0 will be displayed as 7.0.

Sensitivity and specificity of the NADAL® pH test were determined by testing of solutions with known pH values. Specimens up to pH 4.4 are regarded as positive (physiological pH, normal vaginal environment), and values above pH 4.4 were classified as negative (atypical vaginal environment).

Sensitivity: > 99.9%Specificity: 86.4%
Positive predictive value (PPV): 73%
Negative predictive value (NPV): > 99.9 %
Accuracy: 90 %

Among the following substances: Acetaminophen, Ascorbic Acid, Salicylic Acid, Atropine, Caffeine, Glucose, Hemoglobin, Ampicillin, EDTA, Ephedrine, Ibuprofen, Ethanol, Phenylpropylamine, Tetracycline, Human Albumine, Bilirubin, Creatinine, Estradiol, Estriol, 3-Hydroxybutyric Acid, Pregnanediol, Progesterone, Riboflavin, Uric Acid, Urea, Lactic acid, Glycerol, Acetic acid only Haemoglobin interferes with the test results accuracy (in hemоglobin containing solutions the color of hemoglobin prevented a correct reading at visible concentrations).

Test principles:
The NADAL® pH-Test is for determination of the pH value of vaginal fluid. It consists of a vaginal applicator of approx. 8 cm in length with an integrated pH measurement strip which contains a pH indicator with an optimal range of resolution in the spectrum of interest (MERCK pH indicator rods, pH 4.0-7.0, not bleeding, 1.09542.0001). The applicator consists of a round handle area and a cone-shaped insertion stick of approx. 5 cm in length. On one side of the tip of the insertion stick there is a window like opening, where the pH measurement strip is located (pH measurement area). The round handle allows safe handling of the applicator. The test is inserted approx. 1-3 cm into the vagina and the pH measurement area is gently pressed against the back of the vaginal wall. As soon as the pH measurement area gets moistened with vaginal fluid the color change occurs. The vaginal applicator is removed from the vagina and the pH value is read by assigning the color to a value on the provided color scale.

Clinical significance:
Physiological acidity of the vagina (pH values from 3.8 to 4.4) reduce the incidence of pathogen bacteria colonization. Lactobacilli, as a part of the normal vaginal microflora, contribute to keeping the vaginal pH by metabolizing of glycogen released by cells of the upper vaginal wall to lactic acid under the anaerobic conditions present in the mucosa of the vagina.

An increase of the vaginal pH value can be a sign not only of bacterial vaginosis, vaginal infections or STDs but also other conditions like PROM (Premature rupture of membranes) events, estrogen deficiency, postoperative infected wounds, excessive intimate care or antibiotic therapy might affect the pH value.
The pH test can be used as an aid in diagnosing vaginal infections in women showing typical symptoms of infection like inflammation, itching, increased discharge etc. Regular testing of vaginal pH value even in non-symptomatic women will help to identify conditions that support the proliferation of bacteria that might lead to gynecological complaints and complications including sterility.
For pregnant women a major benefit of regular vaginal pH testing is in the reduction of the risk of premature birth. It is known that some pathogens contribute to early contractions or might migrate upwards the vagina causing severe infections that might lead to complications in pregnancy and birth. Regular pH screening will contribute to the identification of these conditions allowing an early treatment of the patients.