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Updated: Aug 10, 2026

Milk Collection in the Rat Using Capillary Tubes and Estimation of Milk Fat Content by Creamatocrit
Published on: December 16, 2015
Milk composition changes--a simple and non-invasive method of detecting ovulation in lactating women
Objective:
To assess the possibility of detecting ovulation through observing changes in composition of milk and using this as a simple and non-invasive method.
Method:
Twenty five normal lactating women (menstruating and non-menstruating), varying in age from 18-35 years and taking no hormonal contraceptives were included in this study. Hormonal estimation was done by radioimmunoassay and changes in milk composition were observed by measuring the concentration of Na+, Cl-, K+ and lactose.
Results:
Changes were observed in milk composition of four menstruating women (ovulatory), characterized by significant increase in concentration of Na+ and Cl- and decrease in concentration of lactose and K+. However, in one non-menstruating woman who was found to have ovulation, these findings could not be observed.
Conclusion:
Results show that the determination of Na+, K+, Cl- and lactose in milk of lactating women have a high value for detection of ovulation.

