Green vaginal discharge is not normal and almost always signals an infection that needs treatment. The most common cause is trichomoniasis, a sexually transmitted infection that affected more than two million people in the United States in 2018 alone. Other possibilities include bacterial vaginosis, gonorrhea, chlamydia, or even a retained foreign object like a tampon.
Trichomoniasis: The Most Common Cause
Trichomoniasis, often called “trich,” is the infection most closely associated with green discharge. It’s caused by a tiny parasite spread through sexual contact. The discharge it produces can range from clear to white, yellowish, or greenish, and it often looks thin, frothy, or bubbly. A fishy smell is another hallmark. Some people also experience itching, burning during urination, or irritation around the vulva.
What makes trich tricky is that many people have no symptoms at all, which means it can be passed back and forth between partners without either person realizing it. When symptoms do appear, they can show up anywhere from 5 to 28 days after exposure, though some people carry the infection for months before noticing anything.
Trich is treated with a prescription antibiotic taken by mouth, typically for seven days. It’s not something you can clear on your own, and sexual partners need treatment at the same time to prevent reinfection. In some cases, your provider can send medication home for your partner directly, without requiring them to come in for a separate visit.
Bacterial Vaginosis
Bacterial vaginosis (BV) happens when the normal balance of bacteria in the vagina shifts, allowing certain types to overgrow. Most people associate BV with grayish or off-white discharge, but it can also appear greenish. The discharge tends to be thin and watery rather than frothy, and it typically has a strong fishy odor that becomes more noticeable after sex.
BV is not a sexually transmitted infection, though sexual activity can trigger it. It’s the most common vaginal infection in women of reproductive age. Like trich, it requires prescription treatment. Over-the-counter yeast infection products won’t help, and using them when you actually have BV can delay proper care.
Gonorrhea and Chlamydia
Both gonorrhea and chlamydia can produce cloudy, yellowish, or green vaginal discharge. These are bacterial STIs that often occur together, and both can be completely silent in many people, especially in the early stages. When discharge does appear, it may be accompanied by pain during urination, bleeding between periods, or pelvic discomfort.
Left untreated, gonorrhea and chlamydia can spread to the uterus and fallopian tubes, causing pelvic inflammatory disease, which can lead to chronic pain and fertility problems. Both infections are curable with antibiotics, though gonorrhea treatment typically requires an injection rather than oral medication alone. If you’re diagnosed with either, your recent sexual partners also need treatment.
Retained Foreign Objects
A forgotten tampon, a piece of a condom, or another object left in the vagina can cause discharge that turns yellow, green, pink, gray, or brown. The giveaway is usually an intensely foul smell that gets worse over time. Other signs include vaginal swelling, redness, pelvic pain, fever, or discomfort when urinating.
This is more common than people realize, and there’s no reason to feel embarrassed about it. If you suspect something is retained, a healthcare provider can remove it quickly. Once the object is out, the discharge and odor typically resolve within a day or two, though antibiotics may be needed if an infection has developed.
Why OTC Treatments Won’t Work
Over-the-counter yeast infection creams and suppositories treat only one thing: yeast overgrowth. Yeast infections produce thick, white, cottage cheese-like discharge, not green discharge. If your discharge is green, using a yeast treatment will do nothing for the underlying cause and can waste valuable time. Every infection that causes green discharge, whether it’s trich, BV, gonorrhea, or chlamydia, requires a prescription.
Self-treating also makes it harder for your provider to get an accurate diagnosis later. Some treatments can temporarily mask symptoms or interfere with test results, which means you might need to wait before being tested.
How the Cause Gets Diagnosed
Your provider will likely take a swab of the discharge and send it for testing. Modern lab tests that detect the genetic material of the infection are far more accurate than older methods like examining a sample under a microscope. Testing can usually check for trich, BV, gonorrhea, and chlamydia from a single swab, and results come back within a few days.
If you’re sexually active, your provider may recommend a full STI panel, since infections like chlamydia and gonorrhea frequently occur without obvious symptoms and can coexist with other infections.
Risks During Pregnancy
Green discharge during pregnancy deserves prompt attention. Untreated trichomoniasis is linked to low birth weight, preterm delivery, and premature rupture of membranes. Gonorrhea and chlamydia carry their own pregnancy risks, including the possibility of passing the infection to the baby during delivery. Treatment is safe during pregnancy and far less risky than leaving the infection untreated.
What to Expect After Treatment
Most infections that cause green discharge clear up within one to two weeks of starting the right antibiotic. During treatment for trich, you should avoid alcohol entirely, as the medication causes severe nausea when combined with it. You should also avoid sex until both you and your partner have finished treatment and symptoms have fully resolved.
If your discharge doesn’t improve within a week of finishing treatment, or if it comes back shortly after, contact your provider. Reinfection from an untreated partner is the most common reason symptoms return, but in rare cases, the infection may be resistant to the first-line medication and a different approach is needed.