Endometrial apoptosis in patients with dysfunctional uterine bleeding

To assess glandular apoptosis in the zona functionalis of proliferative phase endometrium in normal individuals and in patients with dysfunctional uterine bleeding (DUB).

Routinely processed, haematoxylin and eosin-stained endometrial biopsies were assessed in 26 patients with symptomatic menstrual abnormality, mainly menorrhagia, and in 24 controls. All biopsies were in the proliferative phase and had been reported as within normal limits and consistent with the menstrual cycle dates provided. Apoptotic and mitotic figures were counted in a minimum of 100 transversely sectioned endometrial glands in all cases. In 16 biopsies (12 DUB and four controls) apoptosis was further assessed using the in situ terminal deoxynucleotidyl-transferase-mediated 2'-deoxyuridine-5'-triphosphate (dUTP) nick-end labelling (TUNEL) method. Apoptotic figures were identified in most control biopsies averaging 5.6/100 glands, and were significantly increased in biopsies from patients with DUB averaging 13.9/100 glands. There was no difference in mitotic figure counts. Apoptoses tended to be clustered within adjacent glands in both groups and individual glands exhibited both mitotic and apoptotic activity. Application of the TUNEL method gave broad agreement with morphological assessment although approximately 20-25% of typical apoptotic figures were not labelled.

Endometrial glandular apoptosis is present in most normal proliferative phase biopsies and appears increased in some cases of DUB. The significance of this finding is not known but increased apoptosis may serve as a morphological marker of abnormal endometrial development in otherwise normal biopsy specimens.