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Updated: Aug 3, 2026

Evaluation of Mammary Gland Development and Function in Mouse Models
Published on: July 21, 2011
Prolactin level after prolonged lactation: contraceptive evaluation
A study was conducted to evaluate serum prolactin during lactation among 60 mothers with prolonged breastfeeding for 2 years. Patients were classified into 3 groups with 20 in each: lactating for less than 6 months, lactating for 6-12 months, and lactating for 12-24 months. There was hyperprolactinemia during lactation and serum prolactin levels decreased as lactation progressed. After long lactation (over a year), 10 of 20 women were amenorrheic and 10 were menstruating; 6 of the menstruating women were ovulating and 4 nonovulating. Prolonged lactation was found to be relatively successful for family spacing.
A study was conducted to evaluate serum prolactin during lactation among 60 mothers with prolonged breastfeeding for 2 years. Patients were classified into 3 groups with 20 in each: lactating for less than 6 months, lactating for 6-12 months, and lactating for 12-24 months. There was hyperprolactinemia during lactation and serum prolactin levels decreased as lactation progressed. After long lactation (over a year), 10 of 20 women were amenorrheic and 10 were menstruating; 6 of the menstruating women were ovulating and 4 nonovulating. Prolonged lactation was found to be relatively successful for family spacing.
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