Dynamic collagen changes in cervix during the first trimester and decreased collagen content in cervical insufficiency.

OBJECTIVE

To determine the changes in cervical collagen during the first trimester of pregnancy and to evaluate the collagen deficit in cases with a previous diagnosis of cervical insufficiency (CI).

MATERIALS AND

METHODS

Cervical punch biopsies were obtained from 66 patients divided into three groups: patients with recurrent abortions due to CI (CI group; n = 8); first-trimester abortion group (study group; n = 37), subdivided into three groups according their gestational week (<7, 7-9 and 9-12 weeks), and patients with cervical biopsy due to gynecologic reasons (control group; n = 12). Collagen quantity was determined by a biochemical method that measured the levels of hydroxyproline (HOP) in dry cervix tissue.

RESULTS

The HOP concentrations were significantly higher at lower gestational ages (p = 0.001). Collagen quantity was lowest in the CI group compared with other groups (p < 0.001).

CONCLUSION

This study shows collagen component of cervix decreases as pregnancy advances through the first trimester. Cervical collagen concentration is lower in women with a history of CI compared to controls who has not a history of CI.