Skip to content

Measurement of Largest Follicle Diameter in Ovarian Fluid (Ultrasound-Based)

Published: August 9, 2026Updated: August 16, 2026

This test uses ultrasound to measure the largest follicle in your ovaries, which helps evaluate ovarian health and potential fertility.

Quick summary

["Ultrasound checks follicle size to guide reproductive health decisions."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
11846-3
Short code
Ovary.largest follicle Diam.max US.meas
Synonyms
Ovary.largest follicle Diam.max US.meas
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
us-measured
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Is Done

Your healthcare provider may order this test to assess ovarian reserve, monitor ovarian function, or evaluate conditions like polycystic ovary syndrome (PCOS) or unexplained infertility. It’s often part of a broader evaluation for fertility or hormonal health.

What to Expect During the Procedure

You’ll lie on your back with your feet in stirrups. A gel is applied to your abdomen, and a transducer (probe) is moved gently over your pelvis to capture images of your ovaries. The procedure is quick, painless, and doesn’t require preparation beyond wearing loose clothing.

Preparation and Restrictions

No special preparation is needed. Avoid heavy meals before the test, and inform your provider if you have a history of bleeding disorders or pelvic infections.

Results and Follow-Up

Results are typically reviewed by your provider within days. They’ll compare the follicle size to your age, menstrual cycle, and overall health to determine if further testing or treatment is needed. Follow-up may include additional ultrasounds or discussions about fertility options.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Larger follicles can indicate normal ovulation or early-stage ovarian development. Smaller or absent follicles may signal reduced ovarian reserve, which can impact fertility. This measurement helps guide decisions about hormone treatments, egg freezing, or other reproductive interventions.

Short name

Follicle Size Assessment

Frequently asked questions

How long does it take to get my results?
Results are usually available within a few days to a week, depending on your healthcare provider’s workflow. Your provider will discuss them with you during a follow-up visit.
Can I eat or drink before this test?
No special diet is required, but it’s best to avoid heavy meals right before the procedure to ensure comfort. You can drink water as usual.
Is this test painful?
No, this ultrasound is generally painless. You may feel a slight pressure or discomfort from the probe, but it shouldn’t cause significant pain.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy