During an initial examination in the labor room, the nurse notes a large amount of yellow-green or gray frothy and bubbly discharge around the vaginal walls with a foul smell.
The nurse suspects the woman has which type of sexually transmitted infection?

Choice A rationale

Rapid plasma regain is not a standard laboratory test associated with hyperemesis gravidarum. Hyperemesis gravidarum involves significant fluid and electrolyte losses, but rapid plasma regain is not a specific indicator of this condition.

Choice B rationale

A urine culture is used to detect the presence of bacteria in the urine, typically to diagnose a urinary tract infection. While dehydration from hyperemesis gravidarum can increase the risk of a UTI, a urine culture is not a primary anticipated laboratory test for hyperemesis itself.

Choice C rationale

Prothrombin time (PT) is a blood test that measures how long it takes blood to clot. It is used to assess coagulation and is not directly related to the metabolic and electrolyte imbalances caused by hyperemesis gravidarum.

Choice D rationale

Urine ketones are a byproduct of fat breakdown for energy, which occurs when the body is not getting enough glucose. In hyperemesis gravidarum, persistent vomiting can lead to dehydration and starvation, forcing the body to break down fat for energy, resulting in ketonuria (ketones in the urine).

Choice A rationale

Gonorrhea typically presents with a purulent, often thick, yellow discharge. While it can have a foul odor, the description of frothy and bubbly is less characteristic of gonorrhea. Diagnosis usually involves a cervical culture or nucleic acid amplification testing (NAAT).

Choice B rationale

Trichomoniasis, caused by the protozoan *Trichomonas vaginalis*, is characteristically associated with a large amount of yellow-green or gray, frothy, and bubbly vaginal discharge with a distinct, often foul or fishy odor. Microscopic examination of the discharge reveals the motile trichomonads for definitive diagnosis.

Choice C rationale

Chlamydia often presents with a thin or mucopurulent discharge, which may be yellowish, but it is not typically described as frothy or bubbly. Many women with chlamydia are asymptomatic. Diagnosis is usually made through NAAT of cervical or urine samples.

Choice D rationale

Syphilis in its primary stage presents with a painless chancre. Secondary syphilis can involve a generalized rash and flu-like symptoms. Vaginal discharge is not a primary characteristic of either the primary or secondary stages of syphilis. Diagnosis involves serological testing.