In the present work Mg and MgAl thin films were fabricated using physical vapour deposition (PVD) technologies as non-traditional and new nanotechnology methods for designing high performance hydrogen storage materials. The physical vapour deposition technologies allow the formation of metastable metal, alloy and chemical compounds with strictly controlled composition, microstructure and stoichiometry at low temperatures. The synthesis of MgH2, MgAl and Mg(AlH4)2 films has been conducted in two steps: (i) fabrication of thin films employing magnetron sputtering in Ar gas, and (ii) hydrogenation of thin films employing plasma immersion ion implantation technologies. For the first time, chemical compound Mg(AlH4)2 has been synthesized using the deposition of Mg and Al atoms from gas phase in hydrogen plasma (reactive deposition with simultaneously hydrogen implantation). The transformation of Mg thin film to MgH2 takes place at 400 K temperature during hydrogenation in hydrogen plasma. Experimental results showed that hydriding kinetics of Ti-doped Mg film increases and desorption temperature decreases by 60-80 K and the maximum H2-effusion from the Ti-undoped Mg-Al takes place at temperature 475 K, and for the Ti-doped Mg-Al film – at temperature 410 K; the release time of accommodated hydrogen is shorted for the Ti-doped Mg-Al film. The mathematical model of hydrogenation shows that during the process of material irradiation in plasma the concentration of incident ions in... [to full text] / Šiame darbe, panaudojant jonines-plazmines technologijas, sintezuotos Mg, MgH2, Mg-Al ir Mg(AlH4)2 plonos nanokristalinės dangos. Ištirta jų struktūros, paviršiaus morfologijos ir sudėties priklausomybė nuo nusodinimo ir hidrinimo plazmoje technologinių parametrų. Darbe panaudoti plėvelių formavimo metodai: (i) magnetroninis-joninis garinimas Ar dujų aplinkoje; (ii) plonų dangų prisotinimas vandeniliu, panaudojant vandenilio jonų implantacijos iš plazmos technologijas. Šio darbo originalumas susijęs su nepusiausvyrinių plazminių technologijų panaudojimu nanokristalinių medžiagų hidrinimui. Pirmą kartą atlikta metalų hidridų sintezė ir ištirta vandenilio kaupimosi kinetika nanostruktūrinėse medžiagose panaudojant plazminės vandenilio implantacijos technologiją. Gauti rezultatai patvirtina joninių-plazminių technologijų pranašumus, iš kurių svarbiausias - formuojamų plėvelių mikrostruktūros valdymas nanometriniame lygyje. Tyrimo metu, panaudojant vandenilio jonų implantaciją į Mg-Al dangas, pirmą kartą susintezuotas Mg(AlH4)2 hidridas. 5 storio Mg dangų transformacija į MgH2, hidrinimo procesą atliekant vandenilio plazmoje, įvyksta esant 400 K temperatūrai. Eksperimentiniai rezultatai atskleidė, kad Ti priemaišomis legiruotose Mg dangose paspartėja hidridų formavimosi kinetika, o vandenilio desorbcijos temperatūra sumažėja 60-80 K. Vandenilio desorbcijos kinetika Ti priemaišomis legiruotose Mg-Al dangose taip pat yra spartesnė, o jų desorbcijos temperatūra sumažėja 65 K... [toliau žr. visą tekstą]

Relevance After the cochlear implantation 70 per cent of children looses their balance. Number of various kinezitherapheutic exercises are used for developing the balance: exercises on soft, moving surfaces reducing body support area; the ones with „Gymnic�� balls. Music therapy has a modern history, applying it for children with hearing and balance or complex disorder in healing. But classical researches were not made on the issue of what benefit music therapy has on children after cochlear implantation surgery. Dances, games are important for social, emotional, intellectual process of children; it is a natural process optimization mean for preschool children, activity, in context of which, corrective tasks are solved. The object of our research was balance of children, for which cochlear implantation was made. The aim of the research – to deduce an effect of kinezitherapy means to children, to which cochlear implantation was made. Goals: 1. To assess and compare a balance of experimental and control children groups after the cochlear implantation. 2. To assess and compare a balance of experimental and control children groups nine months after the cochlear implantation was made. 3. To evaluate the effect of used kinezetherapy means to children balance. The organization of the research. 32 children whom the cochlear implantation was made took place in the research. They were divided into 2 groups: experimental (n=17) and control (n=15). The research lasted for 9 months. The... [to full text]

Vandenilio, kaip energijos nešėjo gavyba ir saugojimas yra iki šiol neišspręsta problema. Viena iš perspektyvių vandenilio gavybos iš vandens technologijų yra katalitinis vandens skaidymas TiO2 paviršiuje. Šiame darbe nagrinėjama titano dioksido dangų formavimas plazmoje. Plazma formuojama vandens garuose, gauti jonai greitinami elektriniame lauke ir implantuojami į titano tūrį. Tai termodinamiškai nepusiausvyrinis procesas, kurio metu inicijuojama daug kitų procesų, keičiančių medžiagos paviršiaus sudėtį ir struktūrą. Darbe pristatomas fenomenologinis, vienadimensinis plazmos sąveikos su medžiaga modelis, medžiagos paviršinio sluoksnio elementinės sudėties kinetikos modeliavimui. Modelis įvertina keletą vienalaikių medžiagos sąveikos su plazma procesų, tokių kaip joninė implantacija, paviršiaus joninė erozija, adsorbcija, terminė difuzija. Didžiausias dėmesys šiame darbe buvo skiriamas difuzijai ir joninei implantacijai, kaip pagrindiniams masės pernešimo procesams su plazma sąveikaujančios medžiagos tūryje. Buvo pateikta keletas alternatyvių šiuos procesu aprašančių modelių. Darbe pateikiami deguonies koncentracijos profiliai titane, gauti po sąveikos su jonų pluošteliu suformuotu vandens garų plazmoje. Taip pat pateikiamas modelio taikymas šių eksperimentų modeliavimui. Gauti rezultatai taikant skirtingus modelius palyginti tarpusavyje, taip pat su eksperimento rezultatais. / The production and storage of hydrogen as energy carrier is still unsolved problem. One of the most promising hydrogen production technologies is water catalysis reaction on the surface of TiO2. In this work formation of TiO2 films in plasma is studied. Plasma is initiated in water vapour, obtained ions are accelerated in electric field and implanted into the bulk of titanium. It is thermodynamically non-equilibrium process by which many other plasma-material interaction processes occur. The one-dimensional, phenomenological model of ion beam interaction with solids, for the simulation of material surface composition kinetic during the process is presented. Few ion beam–material interaction processes are considered in the model, such as ion implantation, sputtering, adsorption, thermal diffusion. The main attention in this work has been paid to the processes of diffusion and ion implantation, as they are the main mass transport processes. Several alternative models for these processes have been proposed. The experimental oxygen concentration profiles in titanium after irradiation of water vapour plasma are presented. The model has been applied for the simulation of this experiment. Results obtained by different models have been compared.

Šiame darbe, panaudojant jonines-plazmines technologijas, sintezuotos Mg, MgH2, Mg-Al ir Mg(AlH4)2 plonos nanokristalinės dangos. Ištirta jų struktūros, paviršiaus morfologijos ir sudėties priklausomybė nuo nusodinimo ir hidrinimo plazmoje technologinių parametrų. Darbe panaudoti plėvelių formavimo metodai: (i) magnetroninis-joninis garinimas Ar dujų aplinkoje; (ii) plonų dangų prisotinimas vandeniliu, panaudojant vandenilio jonų implantacijos iš plazmos technologijas. Šio darbo originalumas susijęs su nepusiausvyrinių plazminių technologijų panaudojimu nanokristalinių medžiagų hidrinimui. Pirmą kartą atlikta metalų hidridų sintezė ir ištirta vandenilio kaupimosi kinetika nanostruktūrinėse medžiagose panaudojant plazminės vandenilio implantacijos technologiją. Gauti rezultatai patvirtina joninių-plazminių technologijų pranašumus, iš kurių svarbiausias - formuojamų plėvelių mikrostruktūros valdymas nanometriniame lygyje. Tyrimo metu, panaudojant vandenilio jonų implantaciją į Mg-Al dangas, pirmą kartą susintezuotas Mg(AlH4)2 hidridas. 5 storio Mg dangų transformacija į MgH2, hidrinimo procesą atliekant vandenilio plazmoje, įvyksta esant 400 K temperatūrai. Eksperimentiniai rezultatai atskleidė, kad Ti priemaišomis legiruotose Mg dangose paspartėja hidridų formavimosi kinetika, o vandenilio desorbcijos temperatūra sumažėja 60-80 K. Vandenilio desorbcijos kinetika Ti priemaišomis legiruotose Mg-Al dangose taip pat yra spartesnė, o jų desorbcijos temperatūra sumažėja 65 K... [toliau žr. visą tekstą] / In the present work Mg and MgAl thin films were fabricated using physical vapour deposition (PVD) technologies as non-traditional and new nanotechnology methods for designing high performance hydrogen storage materials. The physical vapour deposition technologies allow the formation of metastable metal, alloy and chemical compounds with strictly controlled composition, microstructure and stoichiometry at low temperatures. The synthesis of MgH2, MgAl and Mg(AlH4)2 films has been conducted in two steps: (i) fabrication of thin films employing magnetron sputtering in Ar gas, and (ii) hydrogenation of thin films employing plasma immersion ion implantation technologies. For the first time, chemical compound Mg(AlH4)2 has been synthesized using the deposition of Mg and Al atoms from gas phase in hydrogen plasma (reactive deposition with simultaneously hydrogen implantation). The transformation of Mg thin film to MgH2 takes place at 400 K temperature during hydrogenation in hydrogen plasma. Experimental results showed that hydriding kinetics of Ti-doped Mg film increases and desorption temperature decreases by 60-80 K and the maximum H2-effusion from the Ti-undoped Mg-Al takes place at temperature 475 K, and for the Ti-doped Mg-Al film – at temperature 410 K; the release time of accommodated hydrogen is shorted for the Ti-doped Mg-Al film. The mathematical model of hydrogenation shows that during the process of material irradiation in plasma the concentration of incident ions in... [to full text]

Šio darbo literatūros apžvalgoje aptariami plazmos tipai, plazmos charakteristikos bei sąveika su medžiaga. Aptariama plazminės implantacijos technologija. Trumpai apibūdinama vandens garų plazma ir jos panaudojimas. Apžvelgiama titano oksido struktūra bei jo panaudojimas katalizatorių gamybai, kurie gali būti skirti skaldyti vandens molekules ir gaminti vandenilį. Darbe paaiškinamas magnetroninis nusodinimas bei jo privalumai. Darbo metu buvo oksiduojamas titanas vandens garų plazmoje. Titano oksidacija priklauso nuo daugybės plazmoje vykstančių procesų (adsorbcija, sulaikymas, vakansijų susidarymas ir pan.). Titano oksido panaudojimas yra labai platus dabartiniu metu. Aptariama šio eksperimento technologija bei atliekama oksiduotų titano dangų analizė. SEM, XRD, AES, GDOES analizės metodais buvo tiriama titano dangos oksidacija ir aiškinamas oksidacijos mechanizmas. / Types of plasma, characteristics and plasma interaction with solids are discussed in the literature review of this paper. Also, the plasma immersion ion implantation are described. Water vapour plasma are briefly discussed. Titanium oxide structure and it‘s usage for catalyst which could split water molecules are reviewed. Magnetron deposition are explained in this paper. The titanium film was oxidized by water vapour plasma on experiment. The oxidation of titanium depends on many processes in plasma (adsorption, trapping, formation of oxygen vacancies and etc.). Appliance of titanium oxide is very large in recent times. Experimental technology are discussed and plasma treated films are analysed. Titanium oxidation was analysed by SEM, XRD, AES, GDOES. Oxidation mechanism was explained in this paper.

Analizuojant kochlearinio implanto reikšmę žymiai neprigirdinčių ir kurčių vaikų santykių su aplinka pokyčiams, nors kochlearinė implantacija yra labai efektyvus klausos protezavimo metodas, integruojant ir reabilituojant žymiai neprigirdinčius ir kurčius vaikus visuomenėje, tačiau tai palyginti nauja sritis ir mes neaptikom kitų mokslinių tyrimų, nagrinėjančių šią temą Lietuvoje. Klausa žmogui yra vienas iš pagrindinių komunikacijos būdų tarp aplinkinių ir pasaulio, kuriame jis gyvena. Statistikos duomenimis, per metus maždaug 35 vaikams nustatomas įgimtas kurtumas. Vienas iš būdų padėti klausos negalią turintiems asmenims reabilituotis ir integruotis į visuomenę - tai kochlearinės implantacijos. Pirmoji kochlearinė implantacija ne tik Lietuvoje, bet ir Baltijos šalyse atlikta 1999 metais. Šiuo metu Lietuvoje yra operuoti, 75 vaikai. Mūsų darbo naujumą sudaro tai, kad šis darbas vienas pirmųjų tokio pobūdžio darbų Lietuvoje. Darbo tikslas – išanalizuoti kochlearinio implanto reikšmę žymiai neprigirdinčių ir kurčių vaikų santykių su aplinka pokyčiams. Tyrimo tikslui įgyvendinti sprendžiami šie pagrindiniai uždaviniai: 1. Išsiaiškinti ar tiriami vaikai naudojosi individualiais klausos aparatais iki implantacijos. 2. Išanalizuoti ugdymo įstaigos pasirinkimą priklausomai nuo to, kada buvo atlikta implantacija, iki šešerių metų ir jau sulaukus šešerių metų amžiaus. 3. Ištirti vaikų santykių su aplinkiniais ir bendraamžiais pokyčius iki ir po kochlearinės... [toliau žr. visą tekstą] / Though the Cochlear implantation is an extremely effective prosthetic appliance for the treatment of hard of hearing people, the analysis of the impact of Cochlear implant to the changes of considerably hard of hearing and deaf children relationship with environment required lots of efforts, because this kind of children integration to society is rather new in Lithuania and there is a lack of investigations. Hearing is among the main people communication means which they use for acquiring the world they live in. According to statistics, approximately 35 children are born per annum with the diagnosis of deafness. Thus, Cochlear implantation is one of the ways to help people with hearing disability to rehabilitate and integrate into society. In 1999 the first Cochlear implantation has been performed not only in Lithuania but also in Baltic states. Up till now 75 children have been operated. The novelty of our work is composed since it is one of the first works of this kind in Lithuania. The objective of this paper is to analyze the significance of Cochlear implant to the changes of considerably hard of hearing and deaf children relationship with environment. For the implementation of the objective, the paper has been solving the following exercises: 1. To discover whether the inquiring children have been using their individual hearing-aids till implantation. 2. To analyze the choice of educational institution without reference to the time the implantation has been... [to full text]

<p>Uvod: Infertilitet pogađa 10-15% parova reproduktivnog doba. Vanetesna oplodnja (VTO) je najefikasniji vid tret-mana infertiliteta, ali uprkos značajnom napretku stopa uspeha VTO u proseku iznosi oko 30% po ciklusu. Glavnim razlogom neuspeha smatra se neadekvatan kvalitet embriona, dok se pretpostavlja da u 10-20% slučajeva razlog neuspeha leži u neadekvatnoj receptivnosti uterusa. Na osnovu inicijalnih istraživanja histeroskopija, koja predstvalja zlatni standard u dijagnostici i tretmanu patologije kavuma uterusa, se često izvodi u svakodnevnoj kliničkoj praksi kako bi se povećala uspe&scaron;nost VTO. Uprkos &scaron;irokoj primeni i dalje ne postoji dovoljno kvalitetnih dokaza o realnoj ulozi histeroskopije na ishod VTO kako kod patolo&scaron;kih stanja kavuma tako i rutinski, pre prvog ili rekurentnog poku&scaron;aja VTO. Cilj disertacije bio je da se utvrdi uticaj sprovođenja histeroskopije na ishod VTO, ustanovi učestalost prethodno neprepoznate patologije kavuma uterusa, kao i da se ispitaju stavovi pacijenata o primeni rutinske histeroskopije pred VTO. Materijal i metode: Istraživanje je sprovedeno u Kliničkom centru Vojvodine, u formi prospektivne studije u dve sukcesivne etape od 01.01.2015. do 01.04.2017. U prvoj etapi poređen je ishod VTO kod pacijentkinja kojima pred postupak VTO nije sprovedena histeroskopija (Grupa A), pacijentkinja kod kojih je dobijen uredan nalaz histeroskopije pred postupak VTO (Grupa B) i pacijentkinja gde je pred postupak VTO dobijen patolo&scaron;ki nalaz kavuma na histeroskopiji koji je u istom aktu tertian (Grupa C). Druga etapa istraživanja predstavljala je randomiziranu kontrolisanu studiju (RCT &ndash; randomised controlled trial). Nakon verifikacije urednog ultrazvučnog nalaza pred prvi postupak VTO, pacijentkinje su randomizirane u Grupu A2 kojima pred postupak VTO nije sprovedena histeroskopija i Grupu B2 kojima je pred postupak VTO sprovedena rutinska histeroskopija. Statistička analiza sprovedena je upotrebom odgovarajućeg softvera (JMP Ver. 9). Poređeni su podaci o osnovnim karakteristikama pacijenata, toka i ishoda ciklusa VTO. Primarni parametar ishoda bila je stopa kliničke trudnoće po embriotransferu. Pored analize ishoda primarno konstruisanih grupa, urađena je analiza i naknadno konstruisanih subgrupa, kao i predikcioni model uspeha VTO baziran na logističkoj regresiji. Rezultati: Studija je uključila 253 pacijentkinje (52 pacijentkinja iz Grupe A, 50 iz Grupe B, 50 iz Grupe C, 51 iz Grupe A2 i 50 iz Grupe B2). Nije postojala statistički značajna razlika u karakteristikama pacijentkinja, parametrima ovarijalne rezerve, broju dobijenih jajnih ćelija ni drugim parametrima toka postupka VTO među posmatranim grupama. U prvoj etapi istraživanja dobijena je statistički značajno (p=0,013) veća stopa kliničkih trudnoća kod pacijentkinja kojima je pred postupak VTO sprovedena histeroskopija - 50 % za Grupu B i 42% za grupu C u odnosu na 30,77% kod pacijentkinja bez histeroskopije (Grupa A), bez statistički značajne razlike među histeroskopskim grupama. U drugoj etapi istraživanja stopa kliničkih trudnoća prilikom upotrebe rutinske histeroskopije pred prvu VTO (Grupa B2) iznosila je 46% naspram 31,37% kod pacijentkinja bez histeroskopije pred prvu VTO (Grupa A2), iako uočena razlika nije dostigla statističku značajnost (p =0,089), uz relativan rizik (RR) za ostvarivanje kliničke trudnoće nakon primene histeoskopije uiznosio od 1,47 (95% CI 0,88-2,43) (p=0,13). Analizon subgrupa kod 100 pacijentkinja sa rutinski sprovedenom histeroskopijom pred VTO i 103 pacijentkinje bez histeroskopije pred VTO, dobijena je statistički značajnao veća stopa kliničkih trudnoća (48% naspram 31,07%, istim redom), uz RR od 1,54 (95% CI 1,08-2,20) (p=0,013), kao i stopa tekućih trudnoća od RR 1,49 (CI 1,01-2,19) (p= 0,039). Analiza ukupnog uticaja izvođenja histeroskopije pred VTO dobila je statistički značanjno veću stopu kliničkih trudnoća po ET za grupu histeroskopije uz RR 1,48 (CI 1,06-2,07) (p=0,017). Histeroskopijom je nakon urednog ultrazvučnog nalaza ustanovljeno postojanje patolo&scaron;kog nalaza kod 34,65% pacijenata i to 22,7% major patologije i 11,88% minor patologije kavuma. Nije postojala statistički značajna razlika u uspehu VTO u odnosu na sam nalaz histeroskopije. 98,67% pacijenata podržalo je rutinsku upotrebu histeroskopije pred prvi postupak VTO, dok je 83% pacijenata podržavlo rutinsku upotrebu histeroskopije pred svaki postupak VTO. U finalnom predikcionom modelu se uz AUC od 0,748 jedino postojanje visokokvalitetnog embriona uz odnos &scaron;ansi (OR) 7,91 (95% CI 1,80-56,06; p=0,0047), transfer blastociste uz OR 3,80 (95% CI 1,90-7,98; p=0,0001) i izvođenje histeroskopije pred VTO uz OR 2,13 (95% CI 1,14-4,08, p=0,0169) pokazalo statistički značajnim prediktorima trudnoće. Diskusija: Studija je dobila pozitivan uticaj histeroskopije na ishod postupka VTO, iskazan pre svega povećanjem stope kliničkih trudnoća nakon sprovođenja histeroskopije (bilo da je na histeroskopiji nađen uredan ili patolo&scaron;ki nalaz). Dodatna prednost histeroskopije predstavljala je i i detekcija prethodno nepropoznate patologije kavuma. Umeren efekat na ukupno pobolj&scaron;anje stope kliničkih trudnoća prilikom rutinskog sprovođenja histeroskopije pred prvu VTO, koji je statističku značajnost dostigao tek analizom subgrupa u skladu je sa nalazima novijih dobro dizajniranih studija koji donekle limitiraju nekritičku upotrebu histeroskopije. Biolo&scaron;ko obja&scaron;njenje potencijalnog pozitivnog uticaja histeroskopije najverovatnije leži u detekciji i tretmanu prethodno nepropoznate patologije kavuma, olak&scaron;avanju procedure embriotransfera, kao i humoralnim i molekularnim promenama koje nastaju u endometrijumu kao posledica odgovarajuće histeroskopske traume a koji su u dosa&scaron;anjim istraživanjima apostrofirani kao faktori koji mogu povećati receptivnost uterusa. Zaključak: Histeroskopija je efikasna, bezbedna i visoko prihvatljiva procedura koja dovodi do povećanja uspeha VTO u standardnim kliničkim indikacijama (prethodnog neuspelog postupka VTO i sumnje na patolo&scaron;ki nalaz kavuma uterusa) bilo da se na samoj histeroskopiji nađe uredan ili patolo&scaron;ki nalaz. Rutinska primena histeroskopije pred prvi postupak VTO se na osnovu rezultata studije ne može smatrati apsolutno opravdanom usled statistički nedovoljno značajnog povećanja stope kliničke trudnoće. Uzev&scaron;i u obzir visoku prihvatljivost od strane pacijenata i najverovatniji pozitivan efekat na stopu trudnoće primena rutinske histeroskopije pred prvu VTO bila bi opravdana ukoliko se implementira koncept ambulantne histeroskopije.</p> / <p>Introduction: Infertility affects 10-15% of all couples. In vitro fertilisation (IVF) is the most effective method of infertility treatment, but despite a significant improvement, success rate of IVF is still around 30% per cycle. The main reason for the IVF failure is inadequate embryo quality, but in 10-20% of cases the cause of IVF failure lies in impaired uterine receptivity. Based on earlier studies hysteroscopy, gold standard in the diagnosis and treatment of uterine cavity pathology, is often performed to increase IVF success. Despite its wide use, there is lack of high quality evidence regarding real contribution of hysteroscopy on IVF outcome in situations of uterine cavity pathology or routinely prior to first IVF or after recurrent implantation failure. The aim of this dissertation was to determine the influence of performing hysteroscopy on IVF outcome, as well as the incidence of previously unrecognized uterine pathology, and to examine patient&#39;s attitudes about performing routine hysteroscopy prior to IVF. Material and methods: The research was conducted in a prospective manner in two successive stages at Clinical Center of Vojvodina from 01.01.2015. until 01.04.2017. During first stage of the study IVF outcome was compared between patients who did not have a hysteroscopy prior to IVF (group A), patients with normal hysteroscopic finding prior to the IVF (Group B) and patients with abnormal hysteroscopic findings prior to IVF which was treated at the same time (Group C). The second stage of the study was a randomized controlled trial (RCT). After verification of normal ultrasound findings prior to the first IVF, patients were randomized to group A2 in who me hysteroscopy was not performed and group B2 who had routine hysteroscopy prior to first IVF. Statistical analysis was carried out using the appropriate statistical software (JMP Ver. 9). Patient characteristics, course and outcome of IVF cycle were compared between groups. The primary outcome was clinical pregnancy rate (CPR) per embryotransfer. In addition to analyzing the IVF outcomes in primarily defined groups, subgroup analysis was also performed, as well as IVF success pre-diction model based on logistic regression. Results: The study included 253 patients (52 patients in Group A, 50 in Group B, 50 in Group C, 51 in Group A2 and 50 in Group B2). There was no statistically significant difference in patient characteristics, ovarian reserve parameters, number of retrieved oocytes, or other relevant parameters of IVF course between the observed groups. In the first stage of the study there was statistically significant (p = 0.013) higher clinical pregnancy rate in patients who had a hysteroscopy before IVF - 50% for Group B and 42% for group C versus 30,77 % in patients without hysteroscopy before IVF (Group A), without statistically significant difference between hysteroscopic groups. In the second stage of the study, routine hysteroscopy prior to first IVF (Group B2) led to clinical pregnancy rate 46% versus 31.37% in patients without hysteroscopy prior to first IVF (Group A2), although without statistical significance (p = 0.089. Relative risk (RR) for achieving clinical pregnancy after performing hysteroscopy was 1.47 (95% CI 0.88-2.43) (p = 0.13). Subgroup analysis of 100 patients with routinely performed hysteroscopy before IVF and 103 patients without hysteroscopy prior to the IVF showed statistically significant higher rates of clinical pregnancies (48% versus 31.07%, in the same order), with RR of 1.54 (95% CI 1.08-2.20), (p = 0.013), and for ongoing pregnancies RR was 1.49 (95% CI 1.01-2.19) (p = 0.039). Overall effect of performing hysteroscopy prior to IVF resulted in a statistically significant increase in the clinical pregnancy with RR 1.48 (95% CI 1.06-2.07) (p = 0.017). After normal ultrasound finding hysteroscopy revealed 34.65% of pathological finding, 22.7% of major and 11.88% of minor pathology of the cavity). There was no statistically significant difference in IVF outcome based on hysteroscopy findings. 98.67% of patients supported the routine use of hysteroscopy before the first IVF procedure, while 83% of patients supported the routine use of the hysteroscopy before every IVF procedure. In the final prediction model, with the AUC of 0.748, only the presence of high quality embryos with odds ratio (OR) 7,91 (95% CI 1,80-56,06; p=0,0047), blastocyst transfer with OR 3,80 (95% CI 1,90-7,98; p=0,0001) and performing hysteroscopy prior to IVF with OR 2,13 (95% CI 1,14-4,08, p=0,0169) proved to be statistically significant predictors of pregnancy. Discussion: The study shoved a positive influence of hysteroscopy on the IVF outcome by increasing clinical pregnancy rate after performing hysteroscopy (whether hysteroscopy revealed normal or pathological finding). Additional benefit of hysteroscopy was detection of previously unrecognized uterine pathology. A moderate effect on the overall improvement in clinical pregnancy rate with use of routine hysteroscopy, which reached statistical significance only by subgroup analysis, is in line with findings of recent well designed studies that somewhat limit the noncritical use of hysteroscopy. A biological explanation of the potential positive effect of hysteroscopy is most likely due to detection and treatment of the previously unrecognized uterine pathology, facilitating embryotransfer procedure, as well as the humoral and molecular changes that occur in the endometrium as a consequence of the hysteroscopic trauma. Those changes were hypothesized as factors that can increase uterine receptivity by numerous research. Conclusion: Hysteroscopy is an effective, safe and highly acceptable procedure that increases IVF success when performed for accepted clinical indications (previous IVF failures, pathological findings of uterine cavity), whether hysteroscopy reveals normal or pathological finding. The routine use of hysteroscopy prior to first IVF based on this study can not be considered justified since increase in clinical pregnancy rate did not reach statistical significance. Given the high acceptance of this concept by the patients and moderate but probable positive effect on IVF outcome, implementation of routine hysteroscopy prior to first VTO would be justified only in office hysteroscopy setting.</p>