Sodium in Mother’s Milk (Mass Concentration)
This test measures the amount of sodium present in breast milk, which can help assess electrolyte balance in infants receiving formula or other milk substitutes.
["Understanding sodium levels in breast milk supports infant nutrition and hydration monitoring."]
Key facts at a glance
- LOINC
- 60220-1
- Short code
- Sodium Mother Milk-sCnc
- Synonyms
- Sodium Mother Milk-sCnc
- Category
- electrolyte
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 136
- Ref high
- 145
- Critical range
- 120 N/A – 160 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84295
- SNOMED
- 110741000
- 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 Is This Test Done?
Your healthcare provider may order this test if your infant is receiving formula or other milk-based nutrition and you suspect electrolyte imbalances, or if you’re concerned about hydration or growth patterns. It can also be part of broader evaluations for conditions affecting fluid balance.
What Does the Result Mean?
Sodium levels in breast milk are typically measured to ensure they align with recommended ranges for infant development. While reference ranges vary by lab, abnormal results may indicate potential issues with hydration, kidney function, or metabolic health in the infant.
How Is the Test Performed?
A small sample of breast milk is collected (often via direct milk expression or a breast pump) and sent to a lab. The sample is analyzed using a specialized method to determine sodium concentration, which may involve techniques like ion-selective electrodes or mass spectrometry.
What Are Common Causes of Abnormal Results?
Low sodium levels in breast milk might suggest dehydration, excessive fluid loss, or certain metabolic disorders in the infant. High levels could indicate overhydration, kidney issues, or other metabolic disturbances. Always discuss results with your healthcare provider.
Reference range
Adult: 136-145 mmol/LN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical significance: Sodium is an essential electrolyte that helps maintain fluid balance and nerve function in infants. Abnormal sodium levels in breast milk may indirectly reflect broader health concerns, such as hydration status or metabolic health, and should be evaluated by a healthcare professional.
Frequently asked questions
Why might my healthcare provider ask for this test?
How often is this test done?
Can I prepare my infant or myself for this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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.
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