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11.
OBJECTIVE: To explore the association between mode of delivery and subsequent fertility. METHODS: Deliveries registered in the Medical Birth Registry of Norway were linked to mothers through national identification numbers. The study population was 596,341 women who had their first delivery during 1967-1996, and who were followed up through 2003. We compared rates of continuation to a subsequent birth according to mode of previous delivery (cesarean compared with vaginal). RESULTS: If the first child survived the first year of life, cesarean delivery was associated with a significantly reduced probability of a second birth (relative risk [RR] 0.82, 95% confidence interval [CI] 0.81-0.83 during 1967-1981, and RR 0.88, 95% CI 0.88-0.89 during 1982-1996). Following a stillbirth or an infant loss, the association was less strong during 1967-1981 (RR 0.93, 95% CI 0.89-0.97) and no longer significant during 1982-1996 (RR 1.00, 95% CI 0.97-1.03). A similar pattern was observed from the second to the third birth and in subgroup analyses of women with preeclampsia or breech presentation and in an obstetric low-risk group. CONCLUSION: Cesarean delivery was more strongly associated with reduced fertility if the infant survived than if it was stillborn or died. This suggests that the reduced fertility was to a large degree voluntary and not related to the indication, nor to any physical consequence, of the cesarean delivery. LEVEL OF EVIDENCE: II. 相似文献
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Nuclear morphometry of benign and malignant breast lesions 总被引:1,自引:0,他引:1
F Skj?rten R Kaaresen U Jacobsen P Skaane E Amlie 《European journal of surgical oncology》1991,17(4):350-353
The mean nuclear area (MNA) of mammary gland epithelium was measured in 403 breast specimens, comprising 239 invasive carcinomas, 49 carcinomas in situ, 45 cases of fibrocystic disease (f.c.d.) with intraductal epithelial hyperplasia, and 60 cases of f.c.d. without intraductal hyperplasia. Normal breast tissue adjacent to other benign or malignant lesions was measured in 170 specimens. Statistical analysis revealed no difference between the MNA of invasive ductal carcinoma and ductal carcinoma in situ. The MNA of lobular and ductal carcinomas were significantly different. Significant differences were also found between ductal carcinoma and the two classes of f.c.d. The MNA of f.c.d. with and without intraductal hyperplasia were also significantly different, the former having the highest MNA. All breast lesions showed MNA significantly higher than that of normal breast epithelium. These findings show that there is a gradual increase in MNA from the baseline value of normal breast epithelium, via fibrocystic disease without and with intraductal proliferation to invasive carcinomas. Measurement of MNA may aid in pinpointing cases of intraductal epithelial hyperplasia with malignant potential. 相似文献
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Background/aim
Parents whose first infant had birth defects may worry about a new pregnancy. Our aim was to study pregnancy outcomes among non-malformed second siblings in families where the first birth had a major birth defect.Methods
Data were from the Medical Birth Registry of Norway from 1967 to 2004. Births were linked to their mothers through the unique national identification numbers, providing sibship files with the mother as the observation unit. The study was based on 538,669 singleton first and second full siblings. Families were classified as affected families if the first infant had a major birth defect. Pregnancy outcomes for non-malformed second siblings following affected first births were compared with second siblings in families without malformed infants. Subgroup analyses were done for families where first infants had neural tube defects, cleft lip with or without cleft palate, abdominal wall defects, limb reduction defects, pes equinovarus and congenital dysplasia of the hip.Results
Second siblings in affected families did not differ from those in unaffected families in risk of perinatal death, small for gestational age, preterm birth, placental abruption or preeclampsia. Second siblings following an infant with limb reduction defects had a higher risk of breech presentation than second siblings in unaffected families, also when stratifying on previous siblings in vertex presentation (stratified OR 2.20 [95% C.I. 1.17-4.15]).Conclusion
Parents who proceed to a new pregnancy after a first birth with birth defects may be reassured that, given no recurring defects, there is in general no increased risk of adverse pregnancy outcomes. 相似文献18.
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Thure Filskov Overvad Flemming Skjøth Ida Ehlers Albertsen Torben Bjerregaard Larsen Mette Søgaard Gregory Y.H. Lip 《The American journal of medicine》2021,134(1):67-75.e5
BackgroundWe aimed to investigate whether history of venous thromboembolism should be considered a prognostic factor for future thromboembolic events in patients with atrial fibrillation.MethodsThis was a nationwide cohort study of patients with incident atrial fibrillation from 2000-2017, defined and characterized using Danish health registries. Cox regression analyses were used to calculate hazard ratios and 95% confidence intervals for the outcomes ischemic stroke or systemic embolism, and ischemic stroke, systemic embolism, or venous thromboembolism, according to history of venous thromboembolism. Analyses were adjusted for components of the CHA2DS2-VASc score and time-varying use of oral anticoagulation.ResultsThe study included 246,313 patients with incident atrial fibrillation, of which 6,516 (2.6%) had previous venous thromboembolism. Patients with previous venous thromboembolism carried an overall similar adjusted risk of ischemic stroke or systemic embolism compared with patients without previous venous thromboembolism (reference; hazard ratio 0.99; 95% confidence interval, 0.90-1.09). When analyzing a composite thromboembolic outcome of ischemic stroke, systemic embolism, or venous thromboembolism, patients with previous venous thromboembolism were at high-risk (hazard ratio 1.76; 95% confidence interval, 1.64-1.90). Similar conclusions were drawn when stratifying by venous thromboembolism subtype, and when restricting to patients with low CHA2DS2-VASc scores or the non-anticoagulated subset of the study population.ConclusionPatients with atrial fibrillation and previous venous thromboembolism carried similar risk of ischemic stroke or systemic embolism compared with patients with atrial fibrillation without previous venous thromboembolism. Nonetheless, patients with previous venous thromboembolism remain a high-risk population due to an excess risk of future venous thromboembolism. Patients and physicians should keep this excess thromboembolic risk in mind when weighing the expected risks and benefits of oral anticoagulation in patients with atrial fibrillation. 相似文献
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Klarlund M Ostergaard M Jensen KE Madsen JL Skjødt H Lorenzen I 《Annals of the rheumatic diseases》2000,59(7):521-528
OBJECTIVES: To evaluate synovial membrane hypertrophy, tenosynovitis, and erosion development of the 2nd to 5th metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints by magnetic resonance imaging in a group of patients with rheumatoid arthritis (RA) or suspected RA followed up for one year. Additionally, to compare the results with radiography, bone scintigraphy, and clinical findings. PATIENTS AND METHODS: Fifty five patients were examined at baseline, of whom 34 were followed up for one year. Twenty one patients already fulfilled the American College of Rheumatology (ACR) criteria for RA at baseline, five fulfilled the criteria only after one year's follow up, whereas eight maintained the original diagnosis of early unclassified polyarthritis. The following MRI variables were assessed at baseline and one year: synovial membrane hypertrophy score, number of erosions, and tenosynovitis score. RESULTS: MRI detected progression of erosions earlier and more often than did radiography of the same joints; at baseline the MRI to radiography ratio was 28:4. Erosions were exclusively found in patients with RA at baseline or fulfilling the ACR criteria at one year. At one year follow up, scores of MR synovial membrane hypertrophy, tenosynovitis, and scintigraphic tracer accumulation had not changed significantly from baseline; in contrast, swollen and tender joint counts had declined significantly (p<0.05). CONCLUSIONS: MRI detected more erosions than radiography. MR synovial membrane hypertrophy and scintigraphy scores did not parallel the changes seen over time in clinically assessed swollen and tender joint counts. Although joint disease activity may be assessed as quiescent by conventional clinical methods, a more detailed evaluation by MRI may show that a pathological condition is still present within the synovium. 相似文献