This study was carried out at the Department of Obstetrics and Gynecology, Helsinki University Central Hospital and at the Department of Obstetrics and Gynecology, Jorvi Hospital, during the years 1994-1999.

I am very grateful to Professor Olavi Ylikorkala, M.D., Ph.D., and Professor Markku Seppälä M.D., Ph.D., Heads of the Department of Obstetrics and Gynecology, Helsinki University Central Hospital, for providing me with the facilities to carry out this study and for their interest in my scientific work.

I want to express my deepest gratitute to my supervisor, Docent Aila Tiitinen M.D., Ph.D., first of all for guiding me in scientific research as well as for introducing me to the interesting world of gynecological endocrinology. I am lucky to know her also as a friend and she has the ability to create a positive atmosphere for work and research and she never pushed me too hard to finish my studies.

I am especially grateful to my second supervisor, Jari Sjöberg M.D., Ph.D., for teaching me all that I know about laparoscopy. I admire his experience and talent and he has been an example to me in gynecological surgery. I will never forget the enthusiasm which captured us all during the first years of laparoscopic hysterectomy. He also let me have enough freedom to carry out this thesis.

I want to extend my my thanks to Docent Erkki Kujansuu, M.D., Ph.D., and Docent Risto Mokka, M.D., Ph.D., the official reviewers, for their interest and careful review of the final manuscript. Their valuable comments and constructive criticism greatly improved the text.

I thank warmly Docent Juhani Toivonen, M.D., Ph.D., Head of the Department of Obstetrics and Gynecology, Jorvi Hospital, for continuous support and encouragement. He was always there to help me if something seemed to go wrong and his ideas and stimulating criticism of the manuscipts have been of essential importance for accomplishment of this study. I also want to thank him for his humanity and discussions about life itself.

I am most grateful to Docent Tapio Kurki, M.D., Ph.D., for his cooperation in the Patient Insurance Association. Without his help it would have been impossible to collect all the data concerning the complications. He voluntarily collected many of the patient records and surgical reports for me and he made many valuable comments to improve our manuscripts.

I also thank Docent Ulf-Håkan Stenman, M.D., Ph.D. for his good advise concerning tissue trauma biochemical markers.

I want to express my special thanks to all the members in the working group of gynecological endoscopy, especially Professor Juha Mäkinen, M.D., Ph.D., Professor Pentti Heinonen, M.D., Ph.D., Docent Timo Laatikainen, M.D., Ph.D., Minna Kauko, M.D., Ph.D. and Eija Tómas, M.D., Ph.D., for their collaboration and interest in my work. I have benefited from their wide experience in laparoscopy and enjoyed their pleasant company during many congress trips.

I thank Ms. Anneli Rajamäki for organizing the collection, storage and analysis of the serum samples with such care. I also thank Docent Pentti Kuusela, M.D., Ph.D. for taking care of the interleukin-6 assays and Ms. Liisa Ahola for taking care of the TATI assays.

I also thank Mr. Jari-Matti Lifländer, Ms. Anja Lindholm and Ms. Irma Enroth in the Patient Insurance Association for their cooperation in collecting many patient records from their files.

I am also grateful to Mr. Seppo Pelanteri for calculating the numbers of laparoscopic procedures and hysterectomies from the files of the Finnish Hospital Discharge Register.

I wish to thank Nicholas Bolton, Ph.D., for revising the language of most of my manuscripts and also this doctoral thesis.

I want to express my special thanks to my friends and colleagues in gynecology, Hille Eroila, M.D., Docent Mervi Halttunen, M.D., Ph.D., Maija Harrela, M.D., Riitta Meri, M.D., Päivi Pakarinen, M.D., Ph.D., Raila Suomi, M.D., and Leila Unkila-Kallio, M.D., for their friendship, support and stimulating discussions over twenty years.

I also want to thank all colleagues and other staff in the Departments of Obstetrics and Gynecology in Helsinki University Central Hospital, Jorvi Hospital and the South Karelian Central Hospital for creating a positive attitude for work.

I owe my deep gratitute to my mother, Riitta and my deceased father, Seppo, for giving me a happy childhood in order to succeed in life. I am also very happy to have a brother, Jyrki, and a sister, Reetta, and their families with whom it is possible to share ups and downs. I also thank all my friends, because without them life would have been very boring.

Finally, I want to give heartfelt thanks to Jukka, my husband, for everyday assistance in computer programs when we both tried to survive with our theses and for the twenty-three years we have shared. My two sons, Petteri and Joonas, have brought such happiness to my life that it is impossible to describe.

This study was financially supported by grants from the Research Foundation of Jorvi Hospital, the Clinical Research Institute of Helsinki University Central Hospital and Jorvi Hospital, the Research Foundation of Obstetrics and Gynecology, the Finnish Medical Foundation and the Research Foundation of Orion Corporation.

Helsinki, September 1999

Päivi Härkki-Sirén