In vitro release of cupric ion from intrauterine devices: influence of frame, shape, copper surface area and indomethacin

Re-evaluation of the existing health-based guidance values for copper and exposure assessment from all sources

Copper is an essential micronutrient and also a regulated product used in organic and in conventional farming pest management. Both deficiency and excessive exposure to copper can have adverse health effects. In this Scientific Opinion, the EFSA 2021 harmonised approach for establishing health-based guidance values (HBGVs) for substances that are regulated products and also nutrients was used to resolve the divergent existing HBGVs for copper. The tightly regulated homeostasis prevents toxicity manifestation in the short term, but the development of chronic copper toxicity is dependent on copper homeostasis and its tissue retention. Evidence from Wilson disease suggests that hepatic retention is indicative of potential future and possibly sudden onset of copper toxicity under conditions of continuous intake. Hence, emphasis was placed on copper retention as an early marker of potential adverse effects. The relationships between (a) chronic copper exposure and its retention in the body, particularly the liver, and (b) hepatic copper concentrations and evidence of toxicity were examined. The Scientific Committee (SC) concludes that no retention of copper is expected to occur with intake of 5 mg/day and established an Acceptable Daily Intake (ADI) of 0.07 mg/kg bw. A refined dietary exposure assessment was performed, assessing contribution from dietary and non-dietary sources. Background copper levels are a significant source of copper. The contribution of copper from its use as plant protection product (PPP), food and feed additives or fertilisers is negligible. The use of copper in fertilisers or PPPs contributes to copper accumulation in soil. Infant formula and follow-on formula are important contributors to dietary exposure of copper in infants and toddlers. Contribution from non-oral sources is negligible. Dietary exposure to total copper does not exceed the HBGV in adolescents, adults, elderly and the very elderly. Neither hepatic copper retention nor adverse effects are expected to occur from the estimated copper exposure in children due to higher nutrient requirements related to growth.

Feasibility evaluation of a Cu-38 Zn alloy for intrauterine devices: In vitro and in vivo studies

The existing adverse effects of copper in copper-containing intrauterine devices (Cu-IUDs) have raised concerns regarding their use. These adverse effects include burst release of cupric ions (Cu²⁺) at the initial stage and an increasingly rough surface of the Cu-IUDs. In this study, we investigated the use of two copper alloys, Cu-38 Zn and H62 as the new upgrading or alternative material for IUDs. Their corrosive properties were studied in simulated uterine fluid (SUF) by using electrochemical methods, with pure Cu as a control. We studied the in vitro long-term corrosion behaviors in SUF, cytotoxicity to uterine cells (human endometrial epithelial cells and human endometrial stromal cells), in vivo biocompatibility and contraceptive efficacy of pure Cu, H62, and Cu-38 Zn. In the first month, the burst release rate of Cu²⁺ in the Cu-38 Zn group was significantly lower than those in the pure Cu and H62 groups. The in vitro cytocompatibility Cu-38 Zn was better than that of pure Cu and H62. Moreover, Cu-38 Zn showed improved tissue biocompatibility in vivo experiments. Therefore, the contraceptive efficacy of the Cu-38 Zn is still maintained as high as the pure Cu while the adverse effects are significantly eased, suggesting that Cu-38 Zn can be a suitable potential candidate material for IUDs. STATEMENT OF SIGNIFICANCE: The existing adverse effects associated with the intrinsic properties of copper materials for copper-containing intrauterine devices (Cu-IUD) are of concern in their employment. Such as, burst release of cupric ions (Cu²⁺) at the initial stage and an increasingly rough surface of the Cu-IUD. In this work, Cu alloyed with a high amount of bioactive Zn was used for a Cu-IUD. The Cu-38 Zn alloy exhibited reduced burst release of Cu²⁺ within the first month compared with the pure Cu and H62. Furthermore, the Cu-38 Zn alloy displayed significantly improved biocompatibility and a much smoother surface. Therefore, high antifertility efficacy of the Cu-38 Zn alloy was well maintained, while the adverse effects are significantly eased, suggesting that the Cu-38 Zn alloy is promising for a Cu-IUD.

Women-specific routes of administration for drugs: A critical overview

The woman's body presents a number of unique anatomical features that can constitute valuable routes for the administration of drugs, either for local or systemic action. These are associated with genitalia (vaginal, endocervical, intrauterine, intrafallopian and intraovarian routes), changes occurring during pregnancy (extra-amniotic, intra-amniotic and intraplacental routes) and the female breast (breast intraductal route). While the vaginal administration of drug products is common, other routes have limited clinical application and are fairly unknown even for scientists involved in drug delivery science. Understanding the possibilities and limitations of women-specific routes is of key importance for the development of new preventative, diagnostic and therapeutic strategies that will ultimately contribute to the advancement of women's health. This article provides an overview on women-specific routes for the administration of drugs, focusing on aspects such as biological features pertaining to drug delivery, relevance in current clinical practice, available drug dosage forms/delivery systems and administration techniques, as well as recent trends in the field.

Clinical characteristic and intraoperative findings of uterine perforation patients in using of intrauterine devices (IUDs)

Background

Intrauterine devices (IUDs) are the most popular form of contraception used worldwide; however, IUD is not risk-free. IUD migrations, especially uterine perforations, were frequently occurred in patients. The aim of this study was to investigate the clinical characteristics and intraoperative findings in patients with migrated IUDs.

Results

29 cases of uterine perforation associated with migrated IUDs and 69 control patients were followed between January 2008 to March 2015. Patients who used IUDs within first 6 months from the last delivery experienced a characteristically high rate of the perforation of the uterine wall. A significantly larger number of IUD insertion associated with uterine perforation were performed in rural hospitals or operated at a lower level health care system. There was no clear difference in the age and presented symptoms in patients between two groups. Majority of contraceptive intrauterine devices was the copper-releasing IUDs. Furthermore, patients who used V-shaped IUD showed significantly higher incidence of pelvic adhesions when compared with the users of O-shaped IUDs.

Conclusions

Unique clinical characteristics of IUD migration were identified in patients with uterine perforation. Hysteroscopy and/or laparoscopy were the effective approaches to remove the migrated IUDs. Improving operating skills is required at the lower level of health care system.

New developments in long-acting reversible contraception: the promise of intrauterine devices and implants to improve family planning services

After decades of having the developed world's highest rates of unintended pregnancy, the United States finally shows signs of improvement. This progress is likely due in large part to increased use of highly effective long-acting reversible methods of contraception. These methods can be placed and do not require any maintenance to provide years of contraception as effective as sterilization. Upon removal, fertility returns to baseline rates. This article addresses advances in both software-improved use and elimination of barriers to provide these methods; and hardware-novel delivery systems and devices.