Comparison of Nutrient Content Between Preterm and Term Human Milk: a Systematic Review and Meta-analysis
August 19, 2026 updated by: Li Cai, PhD, Sun Yat-sen University
The purpose of this study is to thoroughly evaluate nutrient disparities between preterm and term human milk.
Study Overview
Status
Completed
Intervention / Treatment
Detailed Description
Preterm birth (gestational age of less than 37 weeks) is a major global health issue, associated with a high burden of mortality and long-term morbidity.
Achieving optimal nutrition is critical for improving outcomes in this vulnerable population.
However, the specific nutritional requirements for supporting postnatal growth akin to intrauterine rates are exceptionally high.
While human milk is the recommended foundation of nutrition, its unfortified use may not meet these demands, and common alternatives like preterm formula present a balance of potential benefits and risks.
Crucially, formulating effective nutritional strategies hinges on a precise understanding of the composition of preterm human milk itself.
Existing evidence on this composition, especially regarding micronutrients and their influencing factors, is inconsistent and incomplete.
Prior reviews have largely focused on macronutrients, leaving a gap in the synthesized evidence regarding micronutrient levels and their key determinants.
Therefore, we performed this systematic review and meta-analysis to quantitatively compare the nutrient profile of preterm and term human milk and to evaluate the influence of factors such as lactation stage on these differences.
Study Type
Observational
Enrollment (Actual)
102
Contacts and Locations
This section provides the contact details for those conducting the study, and information on where this study is being conducted.
Study Locations
-
-
Guangdong
-
Guangzhou, Guangdong, China
- Sun Yat-sen University
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-
Participation Criteria
Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.
Eligibility Criteria
Ages Eligible for Study
- Child
- Adult
- Older Adult
Accepts Healthy Volunteers
Yes
Sampling Method
Probability Sample
Study Population
Among these studies, most of them were performed in Europe.
The sample size ranged from 10 to 2,633, with a median sample size of 49.
All studies provided comparative data from mothers who delivered preterm and term infants, with gestational age consistently categorized as preterm (<37 weeks) and term (≥37 weeks).
The stage of lactation at sample collection (including colostrum, transitional, and mature milk) was reported in most studies.
Description
Inclusion Criteria:
- Studies needed to be population-based observational designs and report nutrient composition data for both preterm and term human milk. They must clearly define gestational age (preterm: 25-36 weeks; term: 37-42 weeks) and examine at least one comparable nutrient in both groups, such as energy, macronutrients (such as protein, fat, lactose), and/or micronutrients (including minerals like calcium and phosphorus, and vitamins such as vitamin D). We included articles published in Chinese or English only.
Exclusion Criteria:
- Studies were excluded if they focused solely on mothers with specific medical conditions (such as malnutrition, mastitis, or diabetes), if they involved nutrient supplementation as an intervention, or if they were published in languages other than Chinese or English.
Study Plan
This section provides details of the study plan, including how the study is designed and what the study is measuring.
How is the study designed?
Design Details
Cohorts and Interventions
Group / Cohort |
Intervention / Treatment |
|---|---|
|
lactating mothers or mothers providing human milk
|
This study is a systematic review and meta-analysis.
No intervention is administered to participants.
Data regarding human milk composition are extracted and synthesized from previously published observational studies.
|
What is the study measuring?
Primary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
Energy content in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The energy content in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Protein in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of protein in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Fat in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of fat in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Lactose in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of lactose in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
Secondary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
Concentration of IgA in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of IgA in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Total nitrogen in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of total nitrogen in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Lysozyme in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of lysozyme in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Lactoferrin in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of lactoferrin in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Lactalbumin in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of lactalbumin in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Albumin in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of albumin in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Sodium in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of sodium in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Potassium in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of potassium in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Calcium in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of calcium in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Magnesium in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of magnesium in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Phosphorus in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of phosphorus in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Zinc in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of zinc in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Copper in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of copper in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Iron in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of iron in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Iodine in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of iodine in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Selenium in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of selenium in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Manganese in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of manganese in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Molybdenum in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of molybdenum in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Vitamin E in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of vitamin E in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Vitamin A in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of vitamin A in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
|
Concentration of Vitamin B6 in human milk
Time Frame: Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
The concentration of vitamin B6 in human milk.
Data will be extracted from included observational studies and expressed as mean ± standard deviation for comparison between preterm and term groups.
|
Human milk samples are collected during the defined lactation periods. Specifically, colostrum is defined as samples collected within 3-5 days postpartum, transitional milk within 7-14 days postpartum, and mature milk at ≥15 days postpartum.
|
Collaborators and Investigators
This is where you will find people and organizations involved with this study.
Sponsor
Study record dates
These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.
Study Major Dates
Study Start (Actual)
July 6, 2022
Primary Completion (Actual)
July 8, 2024
Study Completion (Actual)
September 12, 2025
Study Registration Dates
First Submitted
February 3, 2026
First Submitted That Met QC Criteria
February 3, 2026
First Posted (Actual)
February 10, 2026
Study Record Updates
Last Update Posted (Actual)
August 20, 2026
Last Update Submitted That Met QC Criteria
August 19, 2026
Last Verified
February 1, 2026
More Information
Terms related to this study
Additional Relevant MeSH Terms
Other Study ID Numbers
- HMP
Plan for Individual participant data (IPD)
Plan to Share Individual Participant Data (IPD)?
NO
Drug and device information, study documents
Studies a U.S. FDA-regulated drug product
No
Studies a U.S. FDA-regulated device product
No
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