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Breast Milk Supply Assessment Test Panel

$299.00

+ $6.00 Physician Service Fee

HSA/FSA Accepted

Designed for lactating women experiencing milk supply concerns, this panel tests 12 key biomarkers — including prolactin, thyroid function, and key hormone and nutritional indicators — to help identify underlying factors that may impact supply. Read more

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In the United States, millions of women plan pregnancies, become pregnant, and give birth each year. Each woman’s postpartum journey is deeply personal and unique to her own body and health history. Because no two journeys are the same, feeding experiences can vary widely. Mothers who nurse, pump, or use some combination (including supplementation) are often faced with challenges increasing or maintaining their supply. Low milk supply is one of the most common reasons women stop breastfeeding or pumping earlier than planned. Studies suggest around 35% of lactating women wean before they intend to due to concerns about their supply, often without ever having it formally evaluated.

This panel tests 12 biomarkers to identify hormonal and physical health factors that may be impacting your ability to produce or maintain sufficient milk supply – including thyroid testing (TSH, free T3, and free T4), sex hormones (prolactin, testosterone, and hCG quantitative), an iron panel (iron, TIBC, and ferritin), and insulin & blood sugar markers (insulin, glucose, and HbA1c). A healthy breast milk supply relies heavily on supply and demand (driven by feeding habits), but many other factors can impact a mother’s supply. These factors can include nutritional deficiencies, breast anatomy, hormonal imbalances, and health conditions like polyendocrine metabolic ovarian syndrome (PMOS) (formerly known as polycystic ovary syndrome [PCOS]), diabetes, and insulin resistance. Inadequate breast stimulation and milk removal are the most common causes of low milk supply. Results are intended to be used alongside clinical evaluation by a lactation consultant or other healthcare provider.

No doctor’s visit needed. Buy this breast milk supply test online and visit a nearby Quest location.

Sample type: Blood
Test type: In Person
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This test may be right for you if any of the following are true:

You are postpartum and interested in checking health markers and hormone levels that may affect your breast milk supply
You are experiencing signs of low milk supply and want to understand whether underlying hormonal or physical health factors may be contributing
You have a history of iron deficiency or known hormonal condition such as thyroid dysfunction or PMOS (formerly PCOS) and want to monitor levels alongside other markers to understand if it may be affecting your supply
You have struggled with low supply in a previous pregnancy and want to establish a baseline early
You are considering weaning due to supply concerns and want to rule out underlying physical causes before doing so
You are worried about having an adequate supply and want to see if you have any underlying conditions that may be contributing to a low supply
You are experiencing signs and symptoms of low breast milk supply (see Signs & symptoms section below)

This test is NOT right for you if you are trying to evaluate the composition of your breastmilk, if you have already weaned, or if you are exclusively formula feeding.

Please note: This panel is most appropriate for those who are within 0-6 months postpartum because after that time, the hormone components may no longer be as reliable and next steps may be unclear. It is recommended to use the results of this test in conjunction with clinical evaluation (including a physical exam) by a lactation consultant or other healthcare provider.

This breast milk supply test measures levels of thyroid-stimulating hormone (TSH), free T4, free T3, prolactin, testosterone, hCG, iron, TIBC, ferritin, insulin, glucose, and hemoglobin A1c in your blood. Each of these markers has been known to contribute to conditions that may lower breast milk supply.

Thyroid-stimulating hormone (TSH) levels in the blood are measured to evaluate thyroid function, which is critical for regulating weight, energy, body temperature, mood, and overall health. If your TSH levels are abnormally high or low, this may indicate that your thyroid is either underactive (hypothyroidism) or overactive (hyperthyroidism).

T4 (thyroxine) is a thyroid hormone produced by the thyroid gland and is the main form of thyroid hormone in the blood. Free T4 is not bound to proteins and can enter bodily tissue. Measuring free T4 helps to diagnose hypo- and hyperthyroidism and monitor treatment.

T3 (triiodothyronine) is a thyroid hormone produced by the thyroid gland. Free T3 is not bound to proteins and can enter bodily tissue. Measuring free T3 helps to diagnose and monitor treatment for hyperthyroidism.

Prolactin is a hormone produced by the pituitary gland that is responsible for the development of certain breast tissues, as well as lactation after giving birth. Levels are high in women who are pregnant or have recently given birth and are normally low all other times. High levels can also indicate the presence of a prolactinoma, a benign (noncancerous) tumor in the pituitary gland that can cause irregular periods and hot flashes. Therefore, testing these levels can help your healthcare provider determine if you may have other health issues or are in menopause.

Testosterone is an androgen steroid hormone and the principal male sex hormone, but it is also produced in and important for females. In women, testosterone is secreted in the ovaries and adrenal glands and helps create estrogen and may help regulate how eggs develop in the ovaries.

This test measures total testosterone, which represents all biological pools of testosterone, including the free forms, as well as those bound to proteins in the blood. This test will determine whether your total testosterone level is normal, high, or low, based on your sex.

After delivery, hCG (human chorionic gonadotropin) levels typically decline as the placenta is expelled and pregnancy hormone production stops. In most cases, hCG returns to non-pregnant levels within approximately 2–4 weeks postpartum, although timing can vary from person to person.

Infrequently, hCG may remain elevated for longer than expected. This can occur for a variety of reasons, including residual pregnancy hormone levels during the early postpartum period, retained placental tissue, or a new pregnancy. Retained placental tissue may continue to produce small amounts of hCG and can be associated with changes in postpartum recovery.

hCG can influence postpartum hormonal balance and affect breast milk production. Normal lactation depends on a coordinated shift in hormones after delivery, including a decline in pregnancy-related hormones such as hCG and progesterone.

The following markers are tested to assess different aspects of iron metabolism in your body:

Iron: Measures the amount of iron in your blood. Iron is an essential mineral needed for proper growth and development in the body. Iron is needed by red blood cells to transport oxygen throughout the body. A low iron level can point to anemia, which may be caused by diet, injury or blood loss, pregnancy, heavy exercise, and certain conditions
Total iron binding capacity (TIBC): Measures how well your blood attaches itself to iron to move it around your body
Ferritin: Measures the amount of ferritin in the blood, a protein in the blood that contains iron and helps you understand how much iron your body is storing

Insulin is a hormone produced in the pancreas that helps control blood sugar levels by transporting glucose and fatty acids to muscle, fat, and liver cells. If the cells do not respond to the insulin, then the glucose stays in the blood and blood sugar levels remain high. This is referred to as insulin resistance, which can lead to prediabetes, type 2 diabetes, obesity, CVD, metabolic syndrome, or other conditions.

Glucose is the main sugar found in your bloodstream. The sugar mainly comes from the food you eat and supplies energy to all cells in the body. Blood glucose levels are tightly controlled by hormones like insulin, which is produced in the pancreas. Consistently high blood glucose is typically seen in individuals with uncontrolled or undiagnosed diabetes. In people with diabetes, insulin is either less effective or not produced in sufficient quantity, making it harder to manage the amount of sugar passing through the blood. In type 2 diabetes, the cells become resistant to insulin and ignore its message to absorb glucose, a condition known as insulin resistance. Insulin resistance, a precursor to type 2 diabetes, is strongly associated with atherosclerosis (hardening of the arteries caused by plaque accumulation in the inner lining of an artery).

The HbA1c test is used to measure your average blood sugar levels over the past 3 months. Healthcare professionals use this test to determine disease states such as prediabetes or type 2 diabetes or to help you monitor your levels if you have diabetes. An elevated HbA1c level means that your blood sugar levels have been high over the past 3 months. The HbA1c test reports your blood sugar levels as a percentage.

Hemoglobin is a protein found in red blood cells that carries oxygen from your lungs to the body's tissues and returns carbon dioxide from the tissues back to the lungs. When sugar enters the bloodstream, it attaches and sticks to hemoglobin molecules to form hemoglobin A1c. The HbA1c test is an important tool used for the screening, diagnosis, and management of diabetes.

Signs and symptoms of a low breast milk supply may look different for each woman. If using breast milk to feed their babies, women have options to nurse, pump, supplement, or use a combination of any or all these methods. The most reliable signs of low breast milk supply in exclusively breastfed or combo fed babies are typically related to the baby’s output and weight (poor weight gain, low diaper output, fatigue, showing signs of dehydration, etc.).

Pumping output is sometimes used to estimate breast milk production, but it is not always a reliable indicator of true supply due to the following factors:

Pumping routine and technique (frequency, duration, time of day, use of hand stimulation)
Equipment fit and function (flange size, pump quality, age of pump parts)
Biological factors (medical conditions, storage capacity due to breast anatomy, baby’s age)
Lifestyle and emotional state (hydration, nutrition, drinking alcohol or smoking, taking certain medications, stress vs. relaxation)

If you are concerned about your pumping output or breast milk supply, please speak with your lactation consultant or other healthcare provider.

Purchaser: You must be 18 years of age or older to purchase a test on questhealth.com.

Patient: This test can be performed on patients between 18 and 55 years old.

Sample collection: This test requires sample collection at a Quest Diagnostics location or through Quest Mobile® where available, a convenient location for in-home sample collection*. Collection is not available in AZ, HI, or PR.

*Check your zip code here for service availability, testing may not be available in all locations. Quest Mobile is currently only available for individuals ages 18+.

For most accurate prolactin results, plan to breastfeed or pump 30-45 minutes prior to your specimen collection. Fasting (not eating or drinking anything except water) for 8-12 hours is recommended. Certain supplements and medications can interfere with your test results. If you are concerned about any of your supplements or medications impacting your results, talk to your healthcare provider before your sample is collected to see if you should stop taking them and for how long.

Results are typically available within 4-6 business days of providing your sample - this includes sample processing, testing, and a clinical review before release.

You will receive a secure link to your email when your results are ready. They will be available in a clear, easy-to-read report. If you have, or create, a MyQuest® account, your results may also be available there - and for larger panel tests, you may be able to see individual results as each becomes available.

You may receive an alert call from an independent healthcare coordinator if some of your test results are outside of the expected ranges. Included with your purchase, you have the ability to talk to an independent healthcare provider who can walk you through your results, address any questions or concerns you have, help you think through next steps, and may be able to prescribe treatment for hypothyroidism, if appropriate.

Included with your purchase, you have the ability to discuss your results with an independent healthcare provider who may be able to prescribe hypothyroidism specific treatment depending on your results.

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Please note: Quest Mobile is currently only available for individuals ages 18+.

FAQs

Can I take this test if I am not nursing my baby directly?

Yes. This test can be taken by anyone who is lactating, even if you are pumping instead of nursing the baby directly.

Will this test tell me if my breast milk supply is adequate?

Not directly. This panel tests hormonal and physical health factors that may be contributing to low supply — it does not measure milk volume or output. If results identify an underlying condition, addressing it may help support supply, but this test should always be used alongside evaluation by a lactation consultant or other healthcare provider.

Does a low amount of milk when I pump mean I have a low supply?

Not necessarily. Pumping output is not always an accurate reflection of your actual supply — a breast pump is generally less efficient at removing milk than a nursing baby. If your baby is gaining weight appropriately and producing adequate wet and soiled diapers, your supply is likely sufficient even if pumping yields seem low.

If my results are abnormal, what happens next?

If your results fall outside expected ranges, you may receive a call from an independent healthcare coordinator. An independent healthcare provider will be available to discuss your results and recommend appropriate next steps. For thyroid-related findings, treatment options may be available.

If this test identifies a physical contributor, will it resolve my supply issues?

Not necessarily. If an underlying condition such as a thyroid disorder or nutritional deficiency is identified and treated, supply may improve. However, milk supply is affected by multiple factors and most women benefit from working with a lactation consultant alongside any medical treatment. This test is intended to inform that process, not replace it.

What is perceived insufficient milk (PIM)?

Many women stop breastfeeding early because they believe they are not producing enough milk — a phenomenon known as perceived insufficient milk (PIM). PIM is the primary reason around 35% of lactating women wean earlier than intended, often without ever having their supply formally evaluated. If you are concerned about your supply, this panel can help determine whether an underlying physical or hormonal factor may be contributing.

What are some common causes of low breast milk supply?

The most common causes are missed feedings or pumping sessions, improper latch, or inadequate breast stimulation and emptying. Hormonal imbalances, nutritional deficiencies, and underlying health conditions can also play a role, which is what this panel is designed to help identify.

How can I increase my breast milk supply?

If you are concerned about your supply, working with a lactation consultant is recommended. The most effective approach is increasing the frequency of nursing or pumping — ideally 8 to 12 times in a 24-hour period — as milk production operates primarily on a supply and demand basis. Ensuring your baby has a proper latch, staying well hydrated, and maintaining adequate caloric intake also support supply.

How long does it take to establish my breast milk supply?

Milk typically comes in between 2-3 days postpartum. Most women find their supply becomes fully established and regulated between 6 and 12 weeks postpartum, as production shifts from being hormonally driven to being demand-driven based on feeding frequency. Variation in this timeline is normal.

Are there supplements that can help my breast milk supply?

Potentially. While some women report benefits from certain herbal supplements, most supplements marketed for this have limited clinical evidence supporting their effectiveness. The USDA states that the most reliable way to support supply remains frequent and effective milk removal.¹ Speak with your healthcare provider or lactation consultant before starting any supplement while breastfeeding.

Will medication or diet affect my supply?

Potentially, both can. Certain medications — including some cold and allergy medications containing pseudoephedrine, and some forms of hormonal birth control — can reduce supply. A balanced diet with adequate caloric intake and hydration supports milk production. If you have concerns about a specific medication, speak with your healthcare provider before stopping or changing it.

Will returning to work affect my supply?

Potentially. Returning to work can affect supply if nursing or pumping frequency decreases. Maintaining a consistent pumping schedule at work — ideally matching your baby’s feeding frequency — can help preserve supply. Access to a private space and flexibility in your schedule are generally considered important factors. Planning ahead with a lactation consultant before your return can help minimize disruption.

What lifestyle, diet, or other factors can affect my supply?

Supply can be affected by stress, poor sleep, inadequate hydration, low caloric intake, and infrequent milk removal. Hormonal changes — such as the return of your menstrual cycle — can also cause temporary dips. Smoking and excessive alcohol consumption are known to negatively impact supply. Addressing underlying health conditions, including those this panel is designed to identify, may also play a role.

Does breast size affect my ability to produce enough milk?

No. Breast size is determined by fatty tissue, not by the amount of milk-producing glandular tissue. Women of all breast sizes are generally capable of producing adequate milk. What matters is the frequency and effectiveness of milk removal, not breast size.

Are soft breasts an indicator of low breast milk supply?

No. Breasts feeling softer is a normal sign of supply regulation, typically occurring between 6 and 12 weeks postpartum. It indicates that your body has shifted from overproducing milk to producing closer to what your baby actually needs — not that supply has decreased. Baby output and weight gain remain the most reliable indicators of adequate supply.

What is the difference between this panel and a breast milk lab test that tests milk composition?

These are 2 different types of testing that answer different questions. A breast milk lab test analyzes a sample of your expressed milk to evaluate its nutritional composition — typically measuring fat, protein, carbohydrates, and caloric content. This type of testing focuses on the quality and nutritional value of the milk itself.

This Quest Breast Milk Supply Assessment Test Panel is a blood-based test that looks at your body’s hormonal and physical health to understand factors that may be affecting your ability to produce or maintain sufficient milk supply. Rather than analyzing the milk itself, it examines underlying contributors — including thyroid function, prolactin, hormonal balance, and nutritional levels in your blood — that may be impacting how much milk you are able to make.

The two tests are complement each other. If you are concerned about both your supply and the nutritional quality of your milk, both types of testing may be relevant — but they serve distinct purposes. This panel is not a substitute for a breast milk lab test, and a breast milk lab test will not provide insight into the hormonal or physical factors affecting your supply.

Quest does not offer a breast milk composition lab test.

Can I use my FSA or HSA funds to purchase tests on questhealth.com?

You may be able to use your FSA or HSA funds to purchase lab tests at questhealth.com. Please review your FSA/HSA plan or check with a tax professional to confirm specific requirements for individual eligibility.

Are tests purchased from questhealth.com covered by my health insurance?

Tests purchased on questhealth.com are intended for individuals paying directly—we do not bill insurance, and purchases cannot be submitted for insurance reimbursement.

If your doctor ordered a lab test for you and you are looking to book an appointment for sample collection, you can schedule an appointment here https://appointment.questdiagnostics.com/as-home.

For other questions related to a lab test your doctor ordered for you, including billing and results, you can visit the main Quest Diagnostics site here https://www.questdiagnostics.com.

Our references

National Library of Medicine. Causes of Low Milk Supply: The Roles of Estrogens, Progesterone, and Related External Factors. Accessed June 17, 2026. https://pmc.ncbi.nlm.nih.gov/articles/PMC10831895/
National Library of Medicine. The physiological basis of breastfeeding. Accessed June 17, 2026. https://www.ncbi.nlm.nih.gov/books/NBK148970/
Science Direct. The hormonal physiology of immune components in breast milk and their impact on the infant immune response. Accessed June 17, 2026. https://www.sciencedirect.com/science/article/pii/S0303720723001077
Low Milk Supply Foundation. Chronic lactation insufficiency (CLI) or chronic low milk supply (CLMS). Accessed June 17, 2026. https://www.lowmilksupplyfoundation.org/providers
Advanced Lactation Care. Functional Laboratory Evaluation in Low Breast Milk Supply. Accessed June 17, 2026. https://www.advancedlactationcare.com/post/functional-labs-for-low-milk-supply-investigation-beyond-the-basics
National Library of Medicine. Maternal Perceptions of Insufficient Milk Supply in Breastfeeding. Accessed June 17, 2026. https://pmc.ncbi.nlm.nih.gov/articles/PMC4508856/
Lacta Learning. How Much Milk Should You Expect to Pump? Accessed June 17, 2026. https://lactalearning.com/how-much-milk-should-you-expect-to-pump/
WIC Breastfeeding Support. Low Milk Supply. Accessed June 17, 2026. https://wicbreastfeeding.fns.usda.gov/low-milk-supply

Tests purchased on questhealth.com are only for individuals who intend to pay directly for testing and do not want to submit a claim for reimbursement under their health insurance.

Breast Milk Supply Assessment Test Panel