Objective : To study the ultrastructure of the uterine septum in order to evaluate its role as a possible cause of
pregnancy failure and to discuss the value of hysteroscopic metroplasty in women with recurrent spontaneous abortions.
Patients and methods: This investigation was carried out on 32 women with a history of recurrent abortions and with a
proven septate uterus. They were diagnosed by hysterosalpingography, laparoscopy and/or hysteroscopy. The patients
were subjected to hysteroscopic metroplasty and were followed-up for a period of 6 months to 3 years. Several Biopsies
were taken during the proliferative phase from the upper, middle and lower parts of the uterine septum and from the
lateral uterine wall for comparison. the specimens were processed for both scanning and transmission electron
microscopic examination.
Results : Electron microscopic examination revealed defective preovulatory changes in the septal endometrium
compared to the endometrium of the lateral uterine wall. These changes included reduced number of glandular orifices,
irregular nonciliated cells with few or absent microvilli, incomplete ciliogenesis and reduced ciliated/nonciliated cell
ratio. The uterine septum appeared as a very well-vascularized fibromuscular tissue. It contained numerous smooth
muscle fibers separated by intercellular tissue containing collagen bundles that increased in amount in the lower part of
the septum. Many capillaries and venules were present in the uterine septum. After hysteroscopic metroplasty,
pregnancy occurred in 90% of the cases and H2.2% reached full term.
Conclusion: The classic concept of avascular fihrous septum is no longer acceptable as a possible cause of pregnancy
failure. However, the ultrastructure of the septum, detected in the present study could explain the occurrence of
recurrent abortion. Also, it is concluded that hysteroscopic metroplasty improves the obstetric performance of patients
with recurrent abortions in terms of pregnancy continuation.