Effect of lactation on postpartum uterine involution in rat

ABSTRACT

To see the effect of lactation on uterine involution. Setting: Postgraduate Medical Institute, Lahore. Design: Study of uterine weight and extracellular matrix in rat uterine wall. Subjects: Sixty six mature virgin albino rats. Average age 8 weeks. Average weight 156gms. Group A [non pregnant] 06 animals. Group B [postpartum lactating] 30 animals. Group C [postpartum non lactating] 30 animals. Six animals from group B and C each sacrificed daily from day 1-5 after parturition. Uterine weight increased 10-11 folds on first day after parturition [P <0.01]. The uterine wall was thickened. The collagen fibres were increased through out the uterine wall. They were surrounding groups of muscle fibres and individual myocytes also. Collagen degradation and removal resulted in uterine involution which was accelerated by lactation. Lactation accelerates the process of uterine involution