The effects of decidual injury on the invasion potential of trophoblastic cells.

Objective: To investigate the effect of a decidual incision on trophoblastic invasion potential in vitro.

Methods: Human trophoblast cells were obtained from first-trimester legal terminations of pregnancy. Decidual tissue was retrieved from healthy, low-risk women who underwent an elective cesarean delivery at term. Each dissected decidual sample was divided into four similar-sized samples. The first slice was not treated, the second was incised with a surgical blade to mimic an in vivo injury, the third was incised and immediately repaired with medical adhesive material. This model was used to investigate trophoblastic invasion through a fully repaired decidua. The fourth slice was covered with medical adhesive material only, to exclude any effect of the adhesive material on the decidua. The percent of invasion was calculated as: absorbance of invaded cell×100=invasion index (%). Invasion was expressed as invasion index. The mean and standard deviation of the invasion index were then calculated.

Results: Eight decidual samples were retrieved from eight women. Incised decidua showed a significantly higher mean invasion index (83.3% [±8.1%], P=.012) than the other three models (intact decidua, 69.9% [±5.1%]; incised decidua repaired with adhesive, 66.6% [±8.2%]; intact decidua with adhesive, 58.3% [±11.3%]. There was no significant difference in the invasion index between the other models (P=.4).

Conclusion: Induced decidual injury significantly increased the invasion potential of trophoblastic cells compared with intact decidua. Complete re-approximation of the incised edges reversed this effect in vitro.