High lactation index is associated with insulin sensitivity

Area of Science:

• Reproductive Endocrinology
• Metabolic Health
• Maternal Health

Background:

• Postpartum metabolic changes significantly impact maternal health.
• Insulin sensitivity is crucial for preventing metabolic disorders.
• The role of lactation in long-term metabolic adaptation requires further investigation.

Purpose of the Study:

• To assess the contribution of lactation duration and intensity to insulin sensitivity in women 12-18 months postpartum.
• To explore the relationship between lactation and key metabolic markers, including insulin resistance.

Main Methods:

• Utilized an oral glucose tolerance test (OGTT) to measure glucose and insulin levels.
• Employed the lactation index (LI) scoring system to quantify breastfeeding duration and maintenance.
• Calculated insulin sensitivity using the inverse of the homeostasis model assessment (HOMA(Sens)) and the Cederholm index.
• Performed multiple regression analysis, adjusting for parity, body fat percentage, and breastfeeding status.

Main Results:

• Insulin sensitivity (Cederholm index) showed a positive association with a higher lactation index (P=.01).
• Higher percentage body fat was negatively associated with both HOMA(Sens) and Cederholm index (P<.01).
• Women with the highest lactation index (LI=72) exhibited significantly lower mean 120-minute insulin levels during OGTT.

Conclusions:

• Sustained and prolonged lactation is positively associated with enhanced insulin sensitivity in postpartum women.
• Lactation-associated metabolic adaptations appear protective for maternal metabolic health.
• Body fat percentage is a significant negative predictor of insulin sensitivity, independent of lactation.