Maternal blood B-cell (CD19+) percentages and serum immunoglobulin concentrations correlate with breast-feeding behavior and serum prolactin concentration.
OBJECTIVE
Lactating women recover from pregnancy-induced immunosuppression while actively secreting immunologically active agents into milk. Few clinical studies have examined changes in postpartum maternal immune status or explored mechanisms.


METHODS
We measured blood B-cell (CD19+) percentages and serum concentrations of immunoglobulin (Ig) G, IgM, and IgA at 1 to 2 weeks, 1 month, and 2 months postpartum in a longitudinal study of seven healthy, lactating women.


RESULTS
More frequent or extended breast-feeding sessions were correlated with lower CD19+ percentages, reduced serum IgG, and higher serum IgA and IgM concentrations. CD19+ percentages were correlated negatively with serum prolactin concentrations. Blood samples drawn before and 30 min after breast-feeding did not differ in CD19+ percentages or serum Ig concentrations.


CONCLUSIONS
These findings confirm our previous cross-sectional study showing a negative correlation between CD19+ percentages and serum prolactin. Because lactation practices are modifiable, these findings suggest that women can influence the course of lactation-associated immunologic changes.
Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA.
J P
JP
Zimmer
C
C
Garza
N F
NF
Butte
A S
AS
Goldman
D000328:Adult; D018941:Antigens, CD19 / Q000097:blood*; D001402:B-Lymphocytes / Q000276:immunology*; D001942:Breast Feeding; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D007136:Immunoglobulins / Q000097:blood*; D007774:Lactation / Q000276:immunology*; D008137:Longitudinal Studies; D049590:Postpartum Period / Q000276:immunology*; D011388:Prolactin / Q000097:blood*
D018941:Antigens, CD19; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007136:Immunoglobulins; D011388:Prolactin