Venous thromboembolism and subsequent permanent work-related disability.

Essentials The burden of venous thromboembolism (VTE) related to permanent work-related disability is unknown. In a cohort of 66 005 individuals, the risk of work-related disability after a VTE was assessed. Unprovoked VTE was associated with 52% increased risk of work-related disability. This suggests that indirect costs due to loss of work time may add to the economic burden of VTE. SUMMARY: Background The burden of venous thromboembolism (VTE) related to permanent work-related disability has never been assessed among a general population. Therefore, we aimed to estimate the risk of work-related disability in subjects with incident VTE compared with those without VTE in a population-based cohort. Methods From the Tromsø Study and the Nord-Trøndelag Health Study (HUNT), Norway, 66 005 individuals aged 20-65 years were enrolled in 1994-1997 and followed to 31 December 2008. Incident VTE events among the study participants were identified and validated, and information on work-related disability was obtained from the Norwegian National Insurance Administration database. Cox-regression models using age as time-scale and VTE as time-varying exposure were used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) adjusted for sex, body mass index, smoking, education level, marital status, history of cancer, diabetes, cardiovascular disease and self-rated general health. Results During follow-up, 384 subjects had a first VTE and 9862 participants were granted disability pension. The crude incidence rate of work-related disability after VTE was 37.5 (95% CI, 29.7-47.3) per 1000 person-years, vs. 13.5 (13.2-13.7) per 1000 person-years among those without VTE. Subjects with unprovoked VTE had a 52% higher risk of work-related disability than those without VTE (HR, 1.52; 95% CI, 1.09-2.14) after multivariable adjustment, and the association appeared to be driven by deep vein thrombosis. Conclusion VTE was associated with subsequent work-related disability in a cohort recruited from the general working-age population. Our findings suggest that indirect costs because of loss of work time may add to the economic burden of VTE.

The association of antiphospholipid antibodies with pregnancy-related first time venous thrombosis--a population-based case-control study.

In this population-based case-control study we explored the association of antiphospholipid antibodies with pregnancy-related venous thrombosis. From 1990 through 2003 615 pregnant women were identified at 18 hospitals in Norway with a diagnosis of first time VT. In 2006, 531 of 559 eligible cases and 1092 of 1229 eligible controls were invited for further investigations. The final study population comprised 313 cases and 353 controls, who completed a comprehensive questionnaire and donated a single blood sample, 3-16 years after index pregnancy. We report the results on lupus anticoagulant, anticardiolipin antibodies, and anti-ss(2) glycoprotein-1 antibodies alone, in combination, and with the contribution of the factor V Leiden and the prothrombin gene G20210A polymorphisms. Cut-off values for APAs were chosen according to current international consensus. 29 (9.3%) of the cases and 24 (6.8%) of the controls had at least one positive test for APAs (OR 1.4; 95% CI 0.8-2.5). Nine cases (2.8%) and no controls had more than one positive test (multi-positivity) for APAs. After excluding women with factor V Leiden or prothrombin polymorphisms, still 6 cases were multi-positive for APAs. We conclude that multi-positivity, but not single-positivity, for APAs was weakly associated with a history of ante- and postnatal VT.

Ante- and postnatal risk factors of venous thrombosis: a hospital-based case-control study.

OBJECTIVE: To study ante- and postnatal risk factors of venous thrombosis (VT) in pregnancy. METHODS: A hospital-based case-control study. Cases were women with objectively verified VT during pregnancy or postpartum. Two controls were selected for each case. Validated risk factors were analyzed using chi-square test and logistic regression. RESULTS: In total 559 cases with no prior VT, 268 ante- and 291 postnatal cases were identified together with 1229 controls. Risk factors for antenatal VT were assisted reproduction technique (ART), antepartum immobilization, cigarette smoking, and slight weight gain (<7 kg). Conception after ART and multiple pregnancy had an additive effect, whereas antepartum immobilization and high body mass index (BMI) had a multiplicative effect on the risk for antepartum VT. No other interaction was found between risk factors for antepartum VT. Risk factors for postnatal VT were antepartum immobilization, cigarette smoking, intrauterine fetal growth restriction (IUGR), preeclampsia, emergency cesarean section, postpartum hemorrhage, infection, surgery, and age and parity. Antepartum immobilization, high BMI and reoperation on the indication of bleeding showed multiplicative effects on the risk of postnatal VT. CONCLUSIONS: Ante- and postpartum risk factors differed markedly. More attention should be paid to pregnant women of high BMI who are immobilized.

Time trends in ectopic pregnancies in a Norwegian county 1970-2004--a population-based study.

BACKGROUND: The study objective was to estimate temporal trends in ectopic pregnancy in a well-defined population. METHODS: We identified patients with ectopic pregnancy in hospital discharge registries in Sør-Trøndelag County, Norway, 1970-2004, and retrieved data from medical records. We calculated age-specific ectopic pregnancy incidence, proportions of patients with first ectopic pregnancy/prior infertility treatment, incidence of ectopic pregnancy by birth cohort and age and ratio of ectopic pregnancy to live births (extrauterine ratio) by age and parity. RESULTS: Age-adjusted ectopic pregnancy incidence rates increased from 4.3 to 16.0 per 10 000 women-years over the period 1970-1974 to 1990-1994 and declined to 8.4 per 10 000 women-years in 2000-2004. Incidences were highest among women aged 25-34 years throughout the study period. We observed decreases in proportions of women with previous ectopic pregnancy and with prior infertility treatment after 1990-1994. Incidence rates were the highest for women born between 1960 and 1964 in all age groups. Extrauterine ratio increased with age and was higher for women with two or more previous births compared with women with none or one prior birth. CONCLUSIONS: The epidemic increase in ectopic pregnancy towards 1990-1994 was followed by a marked decrease.

[Can human papillomavirus testing and vaccination prevent cervical cancer?]. / Kan testing og vaksinering for humant papillomavirus forebygge livmorhalskreft?

BACKGROUND: Cervical cancer is the third most frequent cancer among women worldwide. Human papillomavirus (HPV) infection is a necessary risk factor and the first step in cervical carcinogenesis. MATERIAL AND METHODS: This article reviews the current literature concerning the possibility of preventing cervical cancer by HPV testing and vaccination. RESULTS: HPV testing cannot replace cytology, but will reduce false negative cytology and may improve the screening programme for cervical neoplasia. It has not yet been incorporated in any national cervical cancer screening program, but trials are ongoing in Scandinavia and in the Netherlands. The cost-effectiveness of HPV testing in screening has to be proven and whether it can affect the recommended screening-intervals. Therapeutic and prophylactic vaccines for HPV associated disease are in progress. Evaluating the clinical trials that are ongoing will take several years. Several anti-HPV vaccines are now in clinical trials; Norway will also participate. Therapeutic vaccines against cervical cancer have so far not been successful, but anogenital dysplasias and condylomas may be more susceptible. Prophylactic vaccines against HPV 6, 11, 16 and 18 have been evaluated in clinical phase I and II trials, and phase III trials are in progress. INTERPRETATION: HPV testing improves the specificity and sensitivity of cervical cytology and it can be used to clarify cases with atypical cells of undetermined significance (ASCUS) and low-grade intraepithelial neoplasia. In the near future it may also be included in the cervical cancer screening programme for women above the age of 30. The first results in clinical vaccine trials are encouraging, and final conclusions about the effectiveness of these vaccines may be achieved in five years' time.

Primary treatment of cervical carcinoma. Ten years experience from one Norwegian health region.

OBJECTIVE: To study the primary care of cervical carcinoma with regard to clinical and pathological factors, treatment decisions, complications and survival. DESIGN: A historical cohort comprising all women hospitalized with invasive cervical carcinoma (n=293) during the period 1987-1996. RESULTS: Median age was 52 years (range 23-90). FIGO stage distribution was 62%, 15%, 18% and 5% in stages I, II, III and IV, respectively. Early stage disease correlated with young age. Histologic types were: squamous cell carcinoma 84%, adenocarcinoma 11%, adenosquamous carcinoma 4% and small cell/anaplastic carcinoma 1%. Primary therapies were: surgery 188 women (64%), radiotherapy 99 women (34%), chemotherapy two women (0.7%); four women not treated (1.3%). Complications after surgery in 25 women (13%), none were fatal. Acute or late complications after primary or postoperative radiotherapy in 39 women (25%), seven (4.6%) were late serious complications. Three women died from complications related to radiotherapy. Mean follow-up of surviving patients was 58 months. Overall disease specific five-year survival was 70%. Five-year survival in stages IA, IB, II and III was 100%, 88%, 58% and 20%, respectively. One-year survival in stage IV was 31%. Median survival in stages III and IV according to curative or palliative aim of treatment was 20 and 6 months, respectively (p<0.005). CONCLUSION: Satisfactory quality of diagnosis and therapy have been maintained through regional care for cervical cancer patients.

Oral contraceptive failures among women terminating their pregnancy.

BACKGROUND: There are several methodological problems when studying contraceptive efficacy. The present study focuses on efficacy issues from the use of oral contraceptives (OC). METHODS: Through a computerized system of medical records kept at the Department of Gynecology, Regional Hospital of Trondheim, Norway, 800 OC-failure pregnancies were identified among 8192 women having pregnancy termination from January 1, 1987 to December 31, 1996. Ascertainment of cases was done by validating hospital data on OC failures by data collected by the referring practitioner. Inconsistencies in failure data were found among 257 of the 800 (32%) women who claimed at the hospital that an OC was in use at time for conception. The medical record kept by their practitioners stated that 158 women had stopped using OC before last menstrual period, of the remaining 99 women neither data on actual use nor data on prescription could be confirmed. RESULTS: Over the 10-year study period the proportion of failures by brand of OC was remarkably constant from year to year and reflected the user pattern of OCs in Norway. One-third of the total number of failures (n=523) were claimed to be method failures. The annual overall OC-failure rate was estimated to be 1% during the 10-year study. CONCLUSION: Case-control studies focusing on efficacy of OCs must be carefully designed and comprise both women carrying a pregnancy to term as well as women terminating their pregnancies. Our study focused on only one segment of the population of women experiencing an OC failure: women having pregnancy termination. The present study has shown that exposure data collected from interviews have to be validated against prescription data.

Prevalence of GB virus C (also called hepatitis G virus) markers in Norwegian blood donors.

GB virus C (GBV-C), also called hepatitis G virus (HGV), occurs worldwide, but the clinical significance of this virus is still unclear. Plasma samples from 1,001 blood donors were tested by reverse transcription PCR using primers from the NS5 region and by a commercial enzyme-linked immunosorbent assay (ELISA) for the detection of immunoglobulin G antibodies against the putative envelope of HGV (anti-HGV E2). GBV-C/HGV RNA was present in the plasma from 2.5% of the blood donors, and anti-HGV E2 antibodies could be detected in 10.5% of the samples. Only one of the blood donors with viremia had elevated levels of alanine aminotransferase. Among ELISA-positive donors, there was a significantly higher percentage (16.5%) of individuals who had been treated by acupuncture than individuals who had not been given this treatment (9.4%). No other variables showed significant differences. Screening of medical records from 401 recipients of blood from PCR-positive donors revealed no association with liver disease. Four of 12 partners (33%) were HGV RNA positive, and sequence analyses of the strains showed that four of the couples probably were infected with the same strains, while strains from different couples were not identical. Anti-HGV E2 antibodies were detected in serum samples from four other partners. The prevalence of GBV-C/HGV among blood donors in our region is dramatically higher than the prevalence of hepatitis C virus (0.03%).

[Pulmonary embolism among young non-pregnant women]. / Lungeemboli blant yngre ikke-gravide kvinner.

This study focuses on the incidence and risk profile among young women with a diagnosis of pulmonary embolism over the 10-year period 1988-97. A total of 66 non-pregnant women aged 15-44, treated for the first event of pulmonary embolism, were identified by discharge diagnosis at two main Norwegian hospitals (The Regional Hospital of Trondheim and Ullevål Hospital, Oslo). The estimated overall incidence of pulmonary embolism was 6.8 per 100,000 women-years. The crude incidence decreased from 7.5 per 100,000 women-years in 1988-90 to 4.1 per 100,000 women-years in 1996-97 (p < 0.1). 25 (38%) of the 66 patients were identified with at least one medical risk factor, four patients (6%) with a family history of thrombophilia and 30 patients (45%) used oral contraceptives (OC) at the time of diagnosis. 25 (68%) of the 37 patients without registered risk factors used OC. The incidence of pulmonary embolism decreased during the 10-year period, with unchanged risk profile. Two women (3%) died from pulmonary emboli shorter than three weeks after onset of symptoms.

[Deep venous thrombosis in young women in Norway]. / Dyp venetrombose hos yngre kvinner i Norge.

The incidence and distribution of risk factors in non-pregnant women diagnosed with deep vein thrombosis is not well known and was the target of the present study. The medical records of 102 non-pregnant women aged 15-44 hospitalized with deep vein thrombosis at two major Norwegian hospitals were examined retrospectively. The overall incidence of first event of deep vein thrombosis remained fairly constant over the 10-year study period and was estimated at 10.5 per 100,000 women-years. The incidence increased with age and was found twice as high for women 35-44 years of age when compared with the 15-34 age group. Forty-three (42%) of the patients had no identifiable risk factors. Surgery or trauma was found in 37 (36%) of the patients, eight (8%) had a diagnosis of associated cancer, and five (5%) were drug addicts. Five of eight patients registered with immobilization had immobilizing chronic neurological diseases. Thirty-nine (38%) of the patients used oral contraceptives at the time of diagnosis, and 14 of the 39 users of oral contraceptives were identified with medical risk factors. Over the 10-year study period there was no change in the incidence of venous thromboembolism and the risk profile among cases remained constant.

[Reporting of adverse drug reactions to the Norwegian Drug Control Agency]. / Rapportering av legemiddelinduserte helseskadar til Statens legemiddelkontroll.

This article reports on a retrospective study in two major Norwegian hospitals of spontaneous reporting to the Adverse Drug Reaction Committee of the Norwegian Medicines Control Agency of adverse reactions from the use of oral contraceptives (OCs) among patients with a diagnosis of venous thromboembolism. In these two hospitals, 168 women between 15 and 44 were diagnosed with a first event of venous thromboembolism during the ten-year period up to the end og 1997; 69 of them were OC users at the time of diagnosis. Three medical records (4%) kept at the hospital contained information on a report of adverse drug reaction to the Norwegian Medicines Control Agency. The Agency's database of all spontaneous reports on adverse drug reactions contains 112 reports of venous thromboembolism in the context of OC use. These reports came from all over Norway during the ten-year period of our study; four of the reports came from the study hospitals. We conclude that venous thromboembolism during the use of OCs was underreported by more than 90%. This corresponds to estimates of underreporting of other adverse drug reactions from the use of various compounds, in Norway as well as in other countries.

[Sale of oral contraceptives, births and abortions prior to and after the "Marvelon issue"]. / P-pillesal, fødslar og svangerskapsavbrot før og etter "Marvelon-saken".

This study focuses on the situation in Norway after the UK Committee on Safety of Medicines issued an alert on an increased risk of venous thromboembolism with third-generation OCs on 18 October 1995. The Norwegian Medicine Control. Agency immediately issued a press release warning Norwegian women about the health risk associated with third-generation OCs (in Norway, the drug Marvelon only). In this study the effects of the Norwegian warning are evaluated by the use of data on the sale of OCs, number of induced abortions, and births by quarter for the 1992 to 1998 period. From third quarter 1995 to first quarter 1996, sales of Marvelon to pharmacies dropped by 75%, while total sales of OCs were reduced by 5%. From late October 1995 thorough January 1996, approximately 50,000 women stopped taking Marvelon. A maximum increase of 200 induced abortions could be attributed to the negative news on OCs in October and November 1995. There was no subsequent change in the birth pattern. These data confirm that Norwegian women who shifted to another type or stopped taking OCs during the 1995 media crisis avoided unplanned pregnancies.

Retesting and follow-up of first-catch urines from men yield variable results with three Chlamydia trachomatis nucleic acid amplification tests.

First-catch urines from 276 asymptomatic male military recruits were screened by polymerase chain reaction for the detection of Chlamydia trachomatis. Eight initially positive specimens were retested by polymerase chain reaction, ligase chain reaction and transcription-mediated amplification. Urine specimens from six (2.2%) subjects were considered to contain C. trachomatis. However, retesting of serially collected urines from five of these six subjects using different nucleic acid amplification methods showed some discrepancy. This may have a major impact on the efficacy of screening programs for C. trachomatis in low prevalence populations.

[Induction of abortion in the second trimester by prostaglandin vagitories]. / Abortinduksjon med prostaglandinvagitorier i annet trimester.

Medical termination of pregnancy in the second trimester is a painful and a time-consuming procedure. This study comprises 110 consecutive second trimester terminations of pregnancy performed 1994-96. In 76 women (69%) the procedure was a legal abortion due to foetal malformations, 25 women (23%) had an intrauterine foetal death, and in 9 (8%) cases pregnancy was terminated because of persisting drainage of amniotic fluid. All cases with intrauterine foetal death and early drainage of amniotic fluid were successfully treated after application of up to five vagitories of gemeprost (mean 2.8 vagitories; mean induction-abortion interval 8.9 hours). In patients undergoing abortion due to foetal malformations, the mean induction-abortion time was longer (mean 22.7 hours, mean 5.2 vagitories) and 20% did not respond adequately to prostaglandin. Our results show that gemeprost is an efficient means of terminating a pregnancy in cases of foetal death or pre-term amniorrhea, but that it is less efficient in inducing abortion.

[The salpingitis diagnosis under scrutiny]. / Salpingittdiagnosen under lupen.

The rationale for the diagnosis of Pelvic Inflammatory Disease (PID) was studied among hospitalized patients at the Department of Gynaecology, Regional Hospital of Trondheim, Trondheim. From 1 January 1991 to 31 December 1993, 153 patients were discharged with a diagnosis of Pelvic Inflammatory Disease. In retrospect, the diagnoses were reconsidered applying strict criteria. All 26 patients (17%) who had a diagnosis verified by laparoscopy were classified as suffering from a "true" diagnosis, 83 (54%) patients were reconsidered as suffering from a "more likely" and 44 (29% as suffering from a "less likely" diagnosis of Pelvic Inflammatory Disease. Women who had a laparoscopy verified diagnosis of Pelvic Inflammatory Disease, had higher ESR (erythrocyte sedimentation rate), C-reactive protein and temperature when compared with women reclassified as "less likely" suffering from Pelvic Inflammatory Disease. Only 72% of the patients had microbiological sampling from the cervix. In order to increase diagnostic precision we argue for minimum criteria and a systematic clinical examination, including vaginal ultrasound, when diagnosing Pelvic Inflammatory Disease. We recommend more diagnostic use of laparoscopy especially among women with mild symptoms and few objective signs.

The risk-of-malignancy index to evaluate potential ovarian cancers in local hospitals.

OBJECTIVE: To assess the risk-of-malignancy index (a scoring system based on menopausal status, ultrasound features, and serum CA 125) at district hospitals for referral of women with suspected malignant pelvic masses for primary surgery at a central gynecologic oncology unit. METHODS: All seven hospitals in Health Region IV, Norway, agreed to refer women with pelvic masses and risk-of-malignancy indices of 200 or more for centralized primary surgery. In total, 365 women 30 years of age or older, admitted consecutively at the local hospitals, were enrolled in the study from February 1, 1995, to January 31, 1997. RESULTS: Compliance with the study was satisfactory; 84% (65 of 77) of women with risk-of-malignancy indices of at least 200 were referred for centralized primary surgery. Sensitivity and specificity to malignancy were 71% and 92%, respectively, which is in agreement with previous validation of the risk-of-malignancy index in teaching hospital settings. False negatives were due mainly to stage Ia (18 of 24) ovarian cancer, whereas 27 of 28 stage II-IV ovarian cancer cases were identified correctly. CONCLUSION: The risk-of-malignancy index identified women with malignant pelvic masses efficiently. Our study showed the risk-of-malignancy index strategy in a practical setting to be able to centralize primary surgery for advanced ovarian cancer from local hospitals to a subspecialty unit. We recommend the risk-of-malignancy index for detection of patients with advanced ovarian cancer for centralized primary surgery.

Oral contraceptives and thrombosis. From risk estimates to health impact.

OBJECTIVE: The scientific debate on oral contraceptives (OCs) and thrombotic diseases continues unabated. The aim of this survey was to evaluate available scientific data on OCs and thrombotic diseases and to make tentative prescription recommendations of OCs to women with and without various thrombotic risk factors. CONSENSUS: In women 15-29 years old, venous thromboembolism is about twice as common as arterial complications. In women between 30 and 44 years, the number of arterial complications exceeds venous diseases by about 50%. The mortality from arterial diseases is 3.5 times higher than the number of deaths from venous diseases in women below 30 years, and 8.5 times higher in women 30-44 years old. A significant disability is more frequent in women suffering and surviving an arterial complication than in women with venous thromboembolism. Although many important scientific issues still have to be addressed, the available scientific data suggests a differential influence of OCs with second and third generation progestagens on the risk of venous and arterial diseases. OCs with second generation progestagens seem to confer a smaller increase in the risk of venous diseases and a higher increase in risk of arterial complications, compared with OCs containing third generation progestagens. The possible difference on the venous side seems to be smaller than primarily anticipated. RESULTS: Young women without any known risk factor for thrombotic diseases may use any low-dose OC. If OCs are prescribed to women with known risk factors for arterial thrombotic disease; e.g. smoking, diabetes, controlled hypertension, migraine without aura, family disposition of acute myocardial infarction (AMI) or thrombotic stroke, a low-dose pill with a third generation progestagen may have an advantage. If OCs are considered for women with risk factors for venous disease such as severe obesity, varicose veins, family history of VTE or with factor V Leiden mutation, a low-dose combined pill with a second generation progestagen may be preferable. In women above 30 years, OCs with third generation progestagens generally seem to confer less overall thrombotic morbidity, mortality and disability than OCs with second generation progestagens. These women should reconsider, however, the indication of combined OCs in the presence of significant risk factors of thrombotic diseases.

PIP: This article discusses available scientific data on oral contraceptives (OCs) and thrombotic diseases and provides tentative prescription recommendations of OCs to women, with and without various thrombotic risk factors. Several studies concerning OCs and venous thromboembolism (VTE), including the original studies serving as scientific databases, were presented. VTE was twice as common as arterial complications in women 15-29 years old, while arterial complications were 50% higher than VTE in women between 30 and 44 years of age. The mortality of arterial disease was 3.5 times higher than the number of deaths from venous disease in women below 30 years, and 8.5 times higher in women aged 30-44 years. The available scientific data suggests a differential influence of OCs with second and third generation progestagens on the risk of venous and arterial diseases. From this consensus, a low-dose OC was prescribed for young women without any known risk factor for thrombotic diseases. Women with a known risk factor for arterial thrombotic disease, a low-dose pill with a third generation progestogen, may have an advantage while a low-dose pill combined with a second generation progestogen was preferable for women with risk factors for venous disease. In women above 30 years, OCs with third generation progestagens generally seem to confer less overall thrombotic morbidity, mortality, and disability than OCs with second generation progestagens. These women should reconsider, however, the indication of combined OCs in the presence of significant risk factors of thrombotic diseases.

Association between the HLA DQB1*0301 gene and human papillomavirus infection in high-grade cervical intraepithelial neoplasia.

This study describes the distribution of DQB1genes in Norwegian women treated for high-grade cervical intraepithelial neoplasia (CIN). Formalin-fixed, paraffin-embedded tissue sections from 170 biopsy specimens with diagnoses of CIN II (n = 54) or CIN III (n = 116) were DQB1-typed using allele-specific polymerase chain reaction. The follow-up period for cases was 13 to 15 years. The control material comprised blood samples and endocervical brushes from 213 women without CIN. Both cases and controls had previously been human papillomavirus (HPV)-typed. The DQB1*0301 allele was overrepresented among cases compared with controls (odds ratio [OR] = 1.8). Presence of CIN was related to HPV infection, and HPV 16 positivity was significantly associated with the presence of DQB1*0301 (OR 1.8). The DQBI*0301 allele was significantly more prevalent in CIN III than in CIN II cases. The lesions in two women recurred in the follow-up period, one of whom was carrying the DQB1*0301 allele. Women carrying the HLA-DQB1*0301 allele have an increased risk of developing CIN when infected by HPV 16, although there was not an increased frequency of recurrent disease among women carrying this allele.

CO2 laser conization for cervical intraepithelial neoplasia grade II-III: complications and efficacy.

AIMS: To examine per- and postoperative complication rates and efficacy of laser conization in the treatment of cervical intraepithelial neoplasia (CIN) grade II-III. MATERIAL AND METHODS: Eligible for analyses were all women treated with their first laser conization because of CIN II-III during the time-period January 1, 1983 to December 31, 1992. The study population comprises 1081 women who were permanent residents of one Norwegian county (Sør-Trøndelag). All analyses were performed in SPSS applying chi-square for trend, Mann-Whitney test, survival analyses and logistic regression. RESULTS: In total 86 women (8.0%) were observed with one or two (4:86) complications. Bleeding was most frequent (n = 66) followed by symptomatic cervical stenosis (n = 18). Most bleeding complications (74.2%) occurred one to two weeks postoperatively. Both bleeding complications and the occurrence of cervical stenosis were associated with cone height. Three emergency hysterectomies, two for bleeding and one for bladder perforation, were performed. Persistent disease was diagnosed in 1.9% (20:1053) of the women. All women with persistent disease were diagnosed among those with CIN III. Persistent disease was more than 20 times more common among women with disease-involved resection margins compared to those with free resection margins. CONCLUSIONS: Our evaluation of ten years' consistent use of conization by CO2 laser in the treatment of CIN II-III in an unselected population showed a low overall complication rate (8%) and very high efficacy (CIN II 100%, CIN III 98.1%) of the treatment.