Mechanism of action of the intrauterine contraceptive device: evidence for a specific biochemical deficiency in the endometrium

Dislocated intrauterine devices: clinical presentations, diagnosis and management

OBJECTIVE

Intrauterine devices (IUDs) are globally one of the most popular methods of contraception. Uterine perforation is one of the most significant complications of IUD use and commonly occurs at the time of IUD insertion rather than presenting as delayed migration. This paper reports a series of 13 cases of displaced IUDs requiring retrieval by laparoscopy or laparotomy. All the IUDs were copper bearing and most perforations occurred immediately after IUD insertion.

CASES

In two patients with sigmoid colon injury and IUD penetration of the appendix, laparoscopic management had failed and laparotomy was necessary owing to severe obliteration of the pelvic cavity. In one patient laparotomy was the preferred surgical approach owing to acute bowel perforation. In the remaining patients, the displaced devices were successfully removed by laparoscopy.

CONCLUSION

Uterine perforation and IUD migration to the organs in the abdominopelvic cavity are serious complications of IUD insertion and can be successfully managed by laparoscopy, or by laparotomy in the presence of severe pelvic adhesions or unexpected complications.

Enhancing contraception A comprehensive review

This review covers familiar and emerging contraceptive methods, comparing the risks and benefits of each. These basics will help you connect patients with the most acceptable form of contraception for them.

Characterization of copper in uterine fluids of patients who use the copper T-380A intrauterine device

BACKGROUND

The copper intrauterine device (IUD) is a highly effective method of contraception that requires the dissolution of the copper into uterine cavity. However, there is little information about the amount and form of copper in the fluid and whether the presence of this element produces any change in the protein concentration.

METHODS

Twenty-seven women were divided into three groups that had used IUD for about 6 months, 1 year and > or =3 years. The samples were collected during the proliferative phase (Pp), secretory phase (Sp) and menstruation (M). Square-wave anodic stripping voltammetry (SWASV), cyclic voltammetry (CV), high performance liquid chromatography (HPLC) and atomic absorption spectrometry (AAS) were used in this study.

RESULTS

Total copper concentrations were between 3.9 and 19.1 micro g/ml. The mean and standard deviations were as follows: 6 months, 11.4+/-4.7 micro g/ml of copper; 1 year, 11.5+/-7.0 micro g/ml of copper; and 3 years, 6.2+/-1.5 micro g/ml of copper. Total proteins were quantified by measuring the area under the chromatographic peaks. The mean areas obtained with uterine fluid samples from women who used IUDs for 6 months, 1 year and 3 years were 290,013, 538,934 and 201,863 arbitrary units (AU), respectively. The control sample was only 22323.

CONCLUSIONS

The amount of copper released from IUD, although high, is in the form of complexes with proteins. IUDs have a constant copper release for at least 6-12 months. Copper(I) was not detected in the fluid. Copper induces a change in the total protein concentration. The amount of copper released and the amount of proteins is slightly larger during the menstrual stage.

[Degradation of copper IUDs in utero. The process of metallic corrosion. A scanning electron microscope study]

OBJECTIVE

The present investigation was carried out in order to study the process of metallic corrosion of copper IUD's in utero, to precise its dynamics and location along the IUD and to appraise the influence of eventual calcareous deposition.

MATERIAL AND METHODS

A total of 461 copper IUDs representing four standard models were screened by means of optical microscopy. Especially typical samples were studied at higher magnifications under the scanning electron microscope. The obtained data were considered in terms of statistics.

RESULTS

It was possible to demonstrate a preferential corrosive activity in the lower part of the IUD without significant variations between the models. It was also possible to precise the steps of the process, to describe its most characteristic aspects and to study the eventual effect of severe calcareous deposition on corroded copper.

DISCUSSION AND CONCLUSIONS

Intrauterine copper corrosion is a normal process which occurs preferentially in the cervical portion of an IUD and can lead to the total metal loss. Both its initiation and evolution are submitted to strong individual variations. Thick and compact vaterite deposits may thwart copper erosion in case of drastic and rapid deposition.

[I.U.D. degradation in utero as a function of time: the phenomena of calcification. Radiocrystallographic and scanning electron microscopy study]

OBJECTIVE

A study was undertaken in order to determine the frequency of the process of calcareous deposition, to clarify the nature of the deposits, their arrangement along the IUD and their possible influence on the appearance of metrorrhagias.

MATERIAL AND METHODS

A total of 408 coopper IUD's belonging to four standard models were observed by means of optical microscopy at low magnifications. The most typical samples were studied under the scanning electron microscope and deposits analyzed by crystallography. The data were analysed statistically.

RESULTS

It was possible to determine both the frequency and the importance of the process of calcification according to the model of IUD and to the bearing time, to demonstrate a preferential location of concretions and to suspect a sensibility to the phenomenon variable according to the model. It was also possible to clarify the stages of the process of calcification, to describe its most characteristic aspects and to identify the essential component of calcareous deposits.

CONCLUSIONS

Calcification concerns roughly over 50% of IUD's in utero. It occurs preferentially on the fundic portion of an IUD. Obviously, the minimal time required for the phenomenon to start as well as to increase its intensity are submitted to strong individual variations. Concretions are composed of vaterite, a distinct variety of carbonate of calcium. They do not seem to be the primary cause of possible metrorrhagias.

Evaluation of active and passive transport mechanisms in genital tracts of IUD-bearing women with radionuclide hysterosalpingoscintigraphy

The objective of this study was to evaluate the active and passive transport mechanisms in the genital tracts of copper T-200 intrauterine device (IUD)-bearing women. (Tc-99m)HMPAO-labeled spermatozoa and (Tc-99m)-labeled albumin macrospheres were placed into the vagina at midcycle. Serial scintigraphic images were obtained over a period of 2 h. Migration of spermatozoa and particles in the genital tract and the direction of transport related to dominant follicle were evaluated. While active sperm migration was greatly inhibited, the passive transport of the particles was not affected in IUD-bearing women. The direction of radiolabeled particles and spermatozoa was toward the dominant follicle side. Passive transport was not affected, whereas active transport of spermatozoa was strongly inhibited in the genital tract by the presence of the IUD. However, the direction of active and passive transport related to dominant follicle side was unchanged in IUD-bearing women and was preferentially toward the tube ipsilateral to the dominant follicle.

The mechanism of action of hormonal contraceptives and intrauterine contraceptive devices

Modern hormonal contraceptives and intrauterine contraceptive devices have multiple biologic effects. Some of them may be the primary mechanism of contraceptive action, whereas others are secondary. For combined oral contraceptives and progestin-only methods, the main mechanisms are ovulation inhibition and changes in the cervical mucus that inhibit sperm penetration. The hormonal methods, particularly the low-dose progestin-only products and emergency contraceptive pills, have effects on the endometrium that, theoretically, could affect implantation. However, no scientific evidence indicates that prevention of implantation actually results from the use of these methods. Once pregnancy begins, none of these methods has an abortifacient action. The precise mechanism of intrauterine contraceptive devices is unclear. Current evidence indicates they exert their primary effect before fertilization, reducing the opportunity of sperm to fertilize an ovum.