저자는 난소의 이소성 탈락막변화의 발생원인을 규명코저 정상분비말기에 얻은 자궁내막조직(10예), 정상자궁임신시 얻은 내막조직과 난소조직(5예), 난관임신환자(20예)에서 얻은 난관과 난소조직 및 임신 없이 난소에 위탈락막증을 보인 2예의 난소조직에 대하여 조직화학적 검색을 하여 다음과 같은 결론을 얻었다. 1. 탈락막변화는 그 발생 장소나 임신여부와 관계없이 유사한 조직학적 소견과 조직 화학적 반응을 보였다. 2. 탈락막세포는 그 세포질의 주변부에 소량의 점액 물질을 갖고 있으며 그 염색성 으로 보아 중성과 산성이며 변색성을 나타내고 있었다. 3. 탈락막반응은 혈관주변에서 더욱 뚜렸하였으며 발생부위와 관계없이 서로가 유사 한 소견을 보였으므로 국소적인것 보다는 전신적인 인자가 관여하는 것 이라고 생각 된다.

The etiology of ectopic decidual reaction in pregnancy has been supposed to be a variety of factors, such as chorionic gonadotrophic hormone, prolonged progesteronic stimulation or defence mechanism to the chorionic invasions(Nelson & Greene, 1958: Greenblatt & Krafka, 1941), mechanical trauma(Madjerek, 1969), adrenal cortical factor (Bassis, 1956), and effects of cyclic AMP (Leroy, 1974). In order to observe decidual reaction in variable sites, the author used endom etrial tissues obtained from women at late secretory phase, endometrial tissues and ovarian tissues from cases of normal uterine pregnacies and tubal pregnancies, and ovarian tissues from cases showing pseudodeciduosis without pregnancy, then applied several histochemical techniques to those specimens. The follows were ensued: 1. The decidual cells represented similar patterns to routine and special histological techniques in spite of varieties of sites of observation and presence or absence of pregnancy. 2. The decidual cells contained small amount of mucosubstances at the rim of their cytoplasm and they were neutral or acidic in nature. 3. On the ground of the fact that the decidual reactions were found around the blood vessels and they represented similar pattern each other in a variety of organ, the etiologic factor of the ectopic decidua may be ascribed to hormonic effects.