Whether you've been having sex with the same partner for years or it's a one-night-stand, there are few things in the world that set off PANIC alarm bells as loudly as itching in your vagina after sex.

1. Your pH is out of whack.

Having sex can often alter your vagina's delicate balance of pH levels, bringing on a feeling of itchiness, Dr. Bahlani explains. To avoid this, she recommends using a good, organic lubricant, like Uberlube or Good Clean Love. The best lube is water-based, which is compatible with any form of contraception, including condoms, explains Dr. Estafan. Both Uberlube and Good Clean Love are condom-friendly.

The pH level of your vagina should be between 3.8 and 4.2 —aka slightly acidic. "This acidic environment is maintained by lactobacilli, or 'good' bacteria, which keep the vagina protected," says Dr. Estafan. "They create a barrier system that prevents the growth of unhealthy bacteria, and keep yeast at bay."

(On a side note: Products with fragrance, perfume, sulfates, alcohol, parabens, and dyes can also change your vaginal pH. Dr. Estafan recommends BioFemme Lubielle, as its active ingredients of Irish Moss and polysaccharides not only lubricate, but can also have a smoothing and softening effect on the vaginal mucosa.)

2. You might have an infection

Changes in the pH levels of your vagina's microbiome signal there's been a decrease in "good" bacteria and an increase in bad, which can cause an infection, explains Dr. Bahlani. However, this doesn't automatically mean you have a sexually transmitted infection. More commonly, an infection is likely to be bacterial vaginosis or yeast, due to an overgrowth that affects your pH levels.

3. You might have an STI

Itching isn't an automatic sign of an STI, says Dr. Estefan, because according to the CDC, less than 5% of vaginal chlamydia infections and 50% of gonorrhea vaginal infections have symptoms. However, "any time there is a thought of exposure to an STI, [you] should be checked out," she says.

4. You could be experiencing dryness

Not only does natural or bottled lubrication make sex feel more pleasurable, but it also helps prevent itchiness caused by having dry sex. And no, not being wet enough during sex isn't just an older women's problem. In fact, there are several reasons why you could be experiencing lubrication probs, including stress, certain meds you're taking, and various other factors.

5. Your vagina might be inflamed

This one can be harder to diagnose, says Dr. Bahlani, but inflammation can affect your vagina. This can be due to rough sex, says Dr. Estafan, or due to dermatological changes like lichen sclerosis, lichen planus, or vestibulodynia—a condition where sex becomes very painful, says Dr. Bahlani.

        6. You could be having an allergic reaction

Known irritants like parabens and sulfates contained in condoms and lubes could be the reason you're itchy, says Dr. Bahlani.

Another culprit? Spermicide, like Nonoxynol-9, which can cause sensitivities that sometimes present as latex allergies. Testing out non-latex condoms, like SKYN, which is made from polyisoprene, is also worth a try, in case you do have a latex allergy you were unaware of.

7. You're going overboard with your cleaning

So you wanna clean yourself up before sex. That's great! But douching and using heavily-fragranced soaps and body washes on your sensitive vulva region is a big no-no. "It's understandable that women want to feel as clean as possible in that region, but sometimes, it can create more harm," explains Dr. Estafan. Even if you think you're using a super-gentle face cleanser that you paid $40 for (and therefore would never betray you), it's likely not doing you any favors if you're using it on your vagina. Facial products are likely to be pH balanced for your face, not your vulva—and as we've learned, changing the pH of your vagina puts you at an increased risk of yeast infections and bacterial vaginosis.