Observation of the activity of factor VIII in the endometrium of women pre- and post-insertion of three types of IUDs

Current and Emerging Options for the Management of Inherited von Willebrand Disease

Von Willebrand disease (VWD) is the most common inherited bleeding disorder with an estimated prevalence of ~1% and clinically relevant bleeding symptoms in approximately 1:10,000 individuals. VWD is caused by a deficiency and/or defect of von Willebrand factor (VWF). The most common symptoms are mucocutaneous bleeding, hematomas, and bleeding after trauma or surgery. For decades, treatment to prevent or treat bleeding has consisted of desmopressin in milder cases and of replacement therapy with plasma-derived concentrates containing VWF and Factor VIII (FVIII) in more severe cases. Both are usually combined with supportive therapy, e.g. antifibrinolytic agents, and maximal hemostatic measures. Several developments such as the first recombinant VWF concentrate, which has been recently licensed for VWD, will make a more "personalized" approach to VWD management possible. As research on new treatment strategies for established therapies, such as population pharmacokinetic-guided dosing of clotting factor concentrates, and novel treatment modalities such as aptamers and gene therapy are ongoing, it is likely that the horizon to tailor therapy to the individual patients' needs will be extended, thus, further improving the already high standard of care in VWD in most high-resource countries.

Endometrial haemostasis and menstruation

Under normal physiological circumstances menstruation is a highly regulated, complex process that is under strict hormonal control. During normal menstruation, progesterone withdrawal initiates menstruation. The cessation of menstrual bleeding is achieved by endometrial haemostasis via platelet aggregation, fibrin deposition and thrombus formation. Local endocrine, immunological and haemostatic factors interact at a molecular level to control endometrial haemostasis. Tissue factor and thrombin play a key role locally in the cessation of menstrual bleeding through instigation of the coagulation factors. On the other hand, fibrinolysis prevents clot organisation within the uterine cavity while plasminogen activator inhibitors (PAI) and thrombin-activatable fibrinolysis inhibitors control plasminogen activators and plasmin activity. Abnormalities of uterine bleeding can result from imbalance of the haemostatic factors. The most common abnormality of uterine bleeding is heavy menstrual bleeding (HMB). Modern research has shown that an undiagnosed bleeding disorder, in particular von Willebrand disease (VWD) and platelet function disorders, can be an underlying cause of HMB. This has led to a change in the approach to the management of HMB. While full haemostatic assessment is not required for all women presenting with HMB, menstrual score and bleeding score can help to discriminate women who are more likely to have a bleeding disorder and benefit from laboratory haemostatic evaluation. Haemostatic agents (tranexamic acid and DDAVP) enhance systemic and endometrial haemostasis and are effective in reducing menstrual blood loss in women with or without bleeding disorders. Further research is required to enhance our understanding of the complex interactions of haemostatic factors in general, and specifically within the endometrium. This will lead to the development of more targeted interventions for the management of abnormal uterine bleeding in the future.

The risk of deep venous thrombosis associated with injectable depot-medroxyprogesterone acetate contraceptives or a levonorgestrel intrauterine device

OBJECTIVE

To assess the risk of venous thrombosis associated with nonoral contraceptives (ie, injectable depot-medroxyprogesterone acetate contraceptives, hormone [levonorgestrel]-releasing intrauterine devices, a contraceptive patch, or a contraceptive implant).

METHODS AND RESULTS

Analyses were performed in the Multiple Environmental and Genetic Assessment study, a large case-control study on risk factors for venous thrombosis. For the current analyses, we selected premenopausal women, aged 18 to 50 years, who were not pregnant nor within 4 weeks postpartum and were not using oral contraceptives; 446 patients and 1146 controls were included. Injectable depot-medroxyprogesterone acetate contraceptives were associated with a 3.6-fold (95% CI, 1.8- to 7.1-fold) increased risk of venous thrombosis compared with nonusers of hormonal contraceptives. The use of a levonorgestrel intrauterine device was not associated with an increased risk (odds ratio, 0.3; 95% CI, 0.1 to 1.1). Unfortunately, the few women using a contraceptive patch or an implant prevented a reliable estimate of the risk of thrombosis.

CONCLUSIONS

The risk of venous thrombosis was increased for injectable depot-medroxyprogesterone acetate contraceptive users, while we were able to reliably exclude an increased risk associated with levonorgestrel intrauterine device use. Therefore, the latter seems to be the safest option regarding the risk of venous thrombosis.

The use of levonorgestrel-releasing intrauterine system for treatment of menorrhagia in women with inherited bleeding disorders

BACKGROUND

The levonorgestrel-releasing intrauterine system (LNG-IUS) is used commonly by gynaecologists as a contraceptive and to treat menorrhagia. However, its efficacy has not been examined in women with inherited bleeding disorders.

DESIGN

A prospective pilot study.

SETTING

A teaching hospital in north London with a designated haemophilia centre.

POPULATION

Female patients with a known inherited bleeding disorder.

METHODS

Sixteen women with subjective and objective menorrhagia caused by inherited bleeding disorders (13 von Willebrand's Disease, two factor XI deficiency and one Hermansky-Pudlak syndrome), who had previously undergone unsuccessful medical treatment were followed up for nine months after LNG-IUS insertion. Bleeding was measured by pictorial chart and haemoglobin concentration.

RESULTS

All women reported that their periods were improved, pictorial chart scores were lower and 56% became amenorrhoeic. None reported side effects.

CONCLUSION

The LNG-IUS is well tolerated and effective and improves quality of life.

Hormonally impregnated intrauterine systems (IUSs) versus other forms of reversible contraceptives as effective methods of preventing pregnancy

BACKGROUND

In the 1970s a new approach to the delivery of hormonal contraception was researched and developed. It was suggested that the addition of a progestogen to a non-medicated contraceptive device improved its contraceptive action. An advantage of these hormonally impregnated intrauterine systems (IUS) is that they are relatively maintenance free, with users having to consciously discontinue using them to become pregnant rather than taking a proactive daily decision to avoid conception.

OBJECTIVES

To assess the contraceptive efficacy, tolerability and acceptability of hormonally impregnated intrauterine systems (IUSs) in comparison to other reversible contraceptive methods.

SEARCH STRATEGY

Literature was identified through database searches, reference lists and individuals/organisations working in the field. Searches covered the period from 1972 to November 2003.

SELECTION CRITERIA

All randomised controlled trials comparing IUSs with other forms of reversible contraceptives and reporting on pre-determined outcomes in women of reproductive years. The primary outcomes were pregnancy due to method/user failure and continuation rate.

DATA COLLECTION AND ANALYSIS

The quality assessment of studies and data extraction were completed independently by two blinded reviewers. A quality checklist was designed to identify general methodological and contraceptive specific factors which could bias results. Events per women months and single decrement life table rates were extracted where possible for pregnancy, continuation, adverse events and reasons for discontinuation. Events per total number of women at follow up were collected for hormonal side effects and menstrual disturbance. When appropriate, data were pooled at the same points of follow up to calculate rate ratios in order to determine the relative effectiveness of one method compared to another. For the single decrement life table rates, the rate differences were pooled to determine the absolute difference in effectiveness of one method compared to another. Interventions were only combined if the contraceptive methods were similar. Non-hormonal IUDs were divided into three categories for the purpose of comparison with IUSs: IUDs >250mm2 (i.e. CuT 380A IUD and CuT 380 Ag IUD), IUDs <=250mm2 (i.e. Nova-T, Multiload, CuT 200 and CuT 220 IUDs) and non-medicated IUDs.

MAIN RESULTS

Twenty-one RCTs comparing hormonally impregnated IUSs to a reversible contraceptive method met the inclusion criteria and it was possible to include eight of these in the meta-analyses, four comparing LNG-20 IUSs with non-hormonal IUDs, one comparing the LNG-20 IUS with Norplant-2 and three comparing Progestasert with non-hormonal IUDs. No significant difference was observed between the pregnancy rates for the LNG-20 users and those for the IUD >250mm2 users. However, women using the LNG-20 IUS were significantly less likely to become pregnant than those using the IUD <=250mm2. Women using the LNG-20 IUS were more likely to experience amenorrhoea and device expulsion than women using IUDs >250mm2. LNG-20 users were significantly more likely than all the IUD users to discontinue because of hormonal side effects and menstrual disturbance, which on further breakdown of the data was due to amenorrhoea. When the LNG-20 IUS was compared to Norplant-2, the LNG-20 users were significantly more likely to experience amenorrhoea and oligomenorrhoea, but significantly less likely to experience prolonged bleeding and spotting. No other significant differences were observed. Progestasert users were significantly less likely to become pregnant and less likely to continue on the method than non-medicated IUD users after one year, but no significant difference was noted for these two outcomes when Progestasert users were compared to IUD<=250mm2 users. The only other significant differences found in the meta-analyses were that Progestasert users were less likely to expel the device and more likely to discontinue the method because of menstrual bleeding and pain than users of IUDs <=250mm2. REVIEWERS' CONCLUSIONl the device and more likely to discontinue the method because of menstrual bleeding and pain than users of IUDs <=250mm2.

REVIEWERS' CONCLUSIONS

Current evidence suggests LNG-20 IUS users are no more or less likely to have unwanted pregnancies than IUD >250mm2 and Norplant-2 users. The LNG-20 IUS was more effective in preventing either intrauterine or extrauterine pregnancies than IUDs <=250mm2. The contraceptive effectiveness of Progestasert was significantly better than non-medicated IUDs, but no difference was observed when compared to IUDs<=250mm2. Continuation of LNG-20 IUS use was similar to continuation of the non-hormonal IUDs and Norplant-2. Amenorrhoea was the main reason for the discontinuation for the LNG-20 IUS and women should be informed of this prior to starting this method.

Pathophysiology of endometrial bleeding

OBJECTIVES

To review the morphological and molecular events responsible for uterine bleeding in health and disease.

METHODS

Review of pertinent literature focusing on the histology and pathophysiology of normal and abnormal uterine bleeding (AUB).

RESULTS

The seat of normal menstrual bleeding is located in the upper two-thirds of the endometrial mucosa and is recognized by tissue necrosis, disruption of microvasculature, migratory leukocytes and platelet/fibrin thrombi in microvessels. The molecular events responsible for tissue and vascular breakdown are related to the release of proteolytic lysosomal enzymes of endometrial cell and inflammatory cell origin. In cases of AUB, tissue breakdown is located in the superficial layer (subsurface) of the endometrium. It is either focal (breakthrough bleeding) or diffuse (withdrawal bleeding). It is initiated by either chronic endometritis and/or microerosions or vascular fragility due to structural abnormalities of microvessels. Endometritis and microerosions occur in otherwise normal endometrium, polyps, submucosal leiomyomata, atrophy and cancer (organic causes). Primary vascular alterations are found in hyperestrogenic-type endometria, i.e. anovulatory dysfunctional uterine bleeding (DUB) and progestational-type endometrium, i.e. progestational contraceptives and combined, continuous hormonal replacement therapy (HRT) (non-organic causes). Ovulatory DUB and coagulation disorders are not appreciated histologically. These are related to impaired vasoconstriction and fibrinolysis and impaired coagulation factors, respectively.

CONCLUSIONS

Histology may contribute to better understanding of the mechanisms of action that initiate, regulate and lead to AUB. Better insight may trigger in the development of therapeutic procedures that could either prevent or control vascular breakdown which results in unexpected uterine bleeding.

Therapeutic effects of the levonorgestrel-releasing intrauterine system in the treatment of idiopathic menorrhagia

OBJECTIVE

To investigate the effect of the levonorgestrel-releasing intrauterine system (LNG-IUS) in the treatment of idiopathic menorrhagia.

DESIGN

Measurements of menstrual blood loss (MBL), hemoglobin, and serum ferritin before and after LNG-IUS insertion.

SETTING

National Research Institute for Family Planning and Beijing Gynecology and Obstetrics Hospital, Beijing, People's Republic of China.

PATIENT(S)

Thirty-four patients with MBL over 80 mL.

INTERVENTION(S)

Insertion of the LNG-IUS on cycle days 5-7 and follow-up at 3-month intervals for 3 years.

MAIN OUTCOME MEASURE(S)

Measurement of MBL, serum ferritin, and hemoglobin for evaluation of efficacy of treatment.

RESULT(S)

A significant reduction of MBL to 23.4 mL (78.7% decrease), 26.4 mL (83.8% decrease), 2.7 mL (97.7% decrease), and 13.7 mL (85.0% decrease) at 6, 12, 24, and 36 months, respectively. After 6 months, one-third of the patients experienced amenorrhea, and one-fourth, spotting. Hemoglobin increased significantly from 121.5 g/L preinsertion to 135.5 g/L after 36 months, while serum ferritin levels increased significantly from 21.9 ng/mL before insertion to 92.8 ng/mL after 36 months. In women using the LNG-IUS for 3-4 years, the E2 levels in 20 samples were 239.4 pmol/L, P levels were 11.1 nmol/L, and serum LNG levels were maintained at an average of 511 pmol/L.

CONCLUSION(S)

The significant reduction of MBL and the increase in hemoglobin and serum ferritin levels in the treatment of menorrhagia with the LNG-IUS has great implications for women's reproductive health, particularly in developing countries.

Intrauterine devices

The aim of this chapter is to review the worldwide use of intrauterine devices (IUDs) for contraception and the long-term contraceptive efficacy and safety of copper-bearing IUDs. The TCu380A and Multiload Cu375 have a very low failure rate (0.2-0.5%) over 10 years. The main concerns of the use of IUDs are risk of pelvic inflammatory diseases and increased menstrual blood loss and irregular bleeding. Factors associated with an increase in risk of pelvic inflammatory diseases are discussed. Preventive measures can be taken with careful screening of eligible IUD users, technical training and adequate service facilities for provision of IUDs. Levonorgestrel-releasing IUDs have the benefit of reducing menstrual blood loss in addition to high contraceptive efficacy. The copper IUD is the most effective method for emergency contraception. It can prevent over 95% of unwanted pregnancies within 5 days of unprotected intercourse.

Cytological evaluation of angiogenesis in endometrial aspirates

We conducted a comparative study of angiogenesis observed in endometrial aspirates according to histological type. Cytological specimens from 14 cases of proliferative phase endometrium, 21 cases of endometrial hyperplasia and 18 cases of well-differentiated endometrial adenocarcinoma were used in the investigation. Immunohistochemical staining was performed according to standard methods using CD34 monoclonal antibody, and new vessels were examined. New vessels were identified in all of the histological types, but no morphological differences were seen. New vessels were observed in more cases of adenocarcinoma than in cases of normal tissue or hyperplasia, and the differences were significant. The difference between the maximum and minimum rates of occurrence of cell clusters possessing new vessels tended to be greater in adenocarcinoma than in the other tissue types (P < 0.05). Based on the above findings, examination of new vessels appearing in aspirated endometrial specimens appeared to be of help in differential diagnosis, but it also seemed necessary to take changes due to the menstrual cycle etc. into consideration.

Current practice of family planning in China

Current practice of family planning in China is based on the population policy and strategy of the country. Comprehensive contraceptive methods are provided in family planning clinics at all levels. Among the methods used, intrauterine devices and tubal sterilization are most popular. Vasectomy is popular in some provinces. Oral pills, injectables and subdermal implants occupy a small proportion. Incidence of abortion is high due to failure of methods and unprotected intercourse. Attention is paid to the adoption of emergency contraception to prevent unwanted pregnancy. Improvement in quality of care is the key to a successful family planning program. Basic research is essential for development of new contraceptive technology.

The effect of levonorgestrel-releasing intrauterine device (20 micrograms/day) (LNG-IUD-20) on the morphological structure of human endometrium: a study of the endometrial factor VIII activity in the women before and after insertion of LNG-IUD-20 by the digital image analysis

The specimens of endometria were obtained from 18 women using an intrauterine device releasing levonorgestrel at 20 micrograms/day (LNG-IUD-20). An immunoperoxidase reaction, PAP method, with the antiserum of Factor VIII as the primary antibody, was carried out in the endometrial biopsies to detect the Factor VIII activity in the endometrial endothelium before and after insertion of LNG-IUD-20. The immunoperoxidase activity was quantitatively assessed by a computer digital image analyser. The results revealed that there were a lower Factor VIII activity in the endometrial endothelial cells after insertion of LNG-IUD-20 (p < 0.001) when compared with the control. From the results of the present study, it is suggested that the synthesis and release of endometrial endothelial Factor VIII might be inhibited by the insertion of LNG-IUD20.

Immunohistochemical staining of von Willebrand factor in endometrium of women during the first year of Norplant implants use

The mechanisms responsible for Norplant implants-induced menstrual irregularities remain poorly understood. It is unclear whether local changes in endometrial haemostasis are involved. The aim of the present study was to examine the immunohistochemical staining for von Willebrand factor (vWF) in endometrial biopsies taken from 37 women exposed to Norplant implants for 3-12 months and to compare it with 73 controls at various phases of the normal menstrual cycle. The vWF staining intensity was quantified by subjective scoring and by objective computerised colour image analysis. Results from the Norplant implants group were additionally correlated with their bleeding patterns, endometrial histology, and plasma oestradiol (E2) and progesterone (P4) levels. No differences were found between control and Norplant implants subjects in the localization of vWF staining, which was specifically confined to the endothelium of endometrial blood vessels. vWF staining intensity in Norplant implants endometrium was significantly lower than in controls during mid cycle, and reached a mean (+/- SE) level (subjective staining score 2.05 +/- 0.13, n = 37) in the range of the early proliferative and mid secretory phase normal endometrium; nevertheless, it remained significantly higher than that of menstrual and late secretory phase normal endometrium. No significant variations in vWF staining could be related to either the histology of the endometrium or the bleeding pattern of the users. Correlation of vWF staining with either serum E2 or serum P4 prior to biopsy, or to the number of days of Norplant implants exposure revealed no significant relationships. However, vWF staining was positively correlated (r = 0.419, P < 0.01) to the number of bleeding/spotting days within a 90-day reference period prior to biopsies being taken. These results demonstrate that there are major differences in the mechanism responsible for normal menstruation and Norplant implants-induced intermenstrual bleeding and spotting, and show that menstrual disturbances associated with the use of Norplant implants are unlikely to be due to changes in vWF levels in endometrial endothelial cells.