A histological study of fetoscopic membrane defects to document membrane healing.
OBJECTIVE
To evaluate the rate of spontaneous healing in human fetal membranes after fetoscopy.


METHODS
Membranes from patients that had undergone fetoscopic interventions and delivered in one of the two treatment centers were included in the study. The membranes were examined macroscopically for any remaining defects and if present, the size of the defect in chorion and amnion was measured. Subsequently, the defect was excised and stained with HE for histological evaluation. Additional immunohistochemical staining was performed with Ki-67, cytokeratin and vimentin. The proliferation index (percentage of proliferating cells) was calculated in amnion and chorion.


RESULTS
Nineteen membrane defects were included in the study. The median time interval between invasive procedures and delivery was 60 days (range 3-112). All fetoscopic defects (n=19) could be identified in the gestational sac and in none spontaneous closure had occurred. Proliferation indices as measured by inmunohistochemistry were very low (median 2.8%, range 0-7%) in the chorion and 0% in the amnion.


CONCLUSIONS
No evidence of spontaneous membrane healing was found after fetoscopic procedures, suggesting that the membrane defect normally persists until delivery. Absence of amniotic fluid leakage after invasive procedures may be based on mechanisms other than histologic membrane repair.
Gratacós
E
E
Fetal Medicine Unit, Department of Obstetrics, Hospital Universitari Vall d' Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain. egratacos@vhebron.net
Sanin-Blair
J
J
Lewi
L
L
Toran
N
N
Verbist
G
G
Cabero
L
L
Deprest
J
J
D000650:Amnion / Q000293:injuries* / Q000473:pathology; D002823:Chorion / Q000293:injuries* / Q000473:pathology; D005260:Female; D005332:Fetoscopy / Q000009:adverse effects*; D006801:Humans; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011446:Prospective Studies; D014945:Wound Healing