New technologies in contraception

The plasticity of biocompatibility

Biocompatibility concerns the phenomena that occur within the interactions between biomaterials and human patients, which ultimately control the performance of many facets of medical technology. It involves aspects of materials science, many different forms of engineering and nanotechnology, chemistry, biophysics, molecular and cellular biology, immunology, pathology and a myriad of clinical applications. It is not surprising that an overarching framework of mechanisms of biocompatibility has been difficult to elucidate and validate. This essay discusses one fundamental reason for this; we have tended to consider biocompatibility pathways as essentially linear sequences of events which follow well-understood processes of materials science and biology. The reality, however, is that the pathways may involve a great deal of plasticity, in which many additional idiosyncratic factors, including those of genetic, epigenetic and viral origin, exert influence, as do complex mechanical, physical and pharmacological variables. Plasticity is an inherent core feature of the performance of synthetic materials; here we follow the more recent biological applications of plasticity concepts into the sphere of biocompatibility pathways. A straightforward linear pathway may result in successful outcomes for many patients; we may describe this in terms of classic biocompatibility pathways. In other situations, which usually command much more attention because of their unsuccessful outcomes, these plasticity-driven processes follow alternative biocompatibility pathways; often, the variability in outcomes with identical technologies is due to biological plasticity rather than material or device deficiency.

Preliminary study on the effect of four-phasic estradiol valerate and dienogest (E2V/DNG) oral contraceptive on the quality of sexual life

INTRODUCTION

A new oral contraceptive containing the natural estrogen estradiol and a 19-nortestosterone derivate dienogest (DNG) in a four-phasic 28-day regimen may be used by women.

AIM

To investigate the quality of sexual life of healthy women on estradiol valerate and DNG (E2V/DNG) oral contraceptive.

METHODS

Fifty-seven women (age range 18-48 years) were enrolled. The Short Form-36 (SF-36) questionnaire to assess quality of life (QoL) was administered at baseline and at the 26th day of both the 3rd and 6th cycles of oral contraceptive (OC) intake. The Short Personal Experience Questionnaire (SPEQ) to measure the change of sexual behavior was used at the 2nd, 7th, 14th, 21st, 26th, and 28th days of the baseline cycle, as well as at the same days of both the 3rd and 6th cycle of contraceptive intake.

MAIN OUTCOME MEASURE

The SF-36 and the SPEQ questionnaires.

RESULTS

Women reported QoL improvement at the 3rd (P < 0.05) and at the 6th cycles (P < 0.01). By SPEQ, improvement of sexuality during the 3rd and the 6th cycle with respect to baseline experience was observed (P < 0.05). The frequency of sexual activity remained basically unchanged (P = NS). Enjoyment and desire improved at the 6th cycle with respect to the 3rd cycle (P < 0.05). All women reported decreased dyspareunia at the 3rd and 6th cycles (P < 0.05). Interestingly, desire, arousal, orgasm, enjoyment, and sexual activity improved, reaching a peak around the 14th day of the menstrual cycle (P < 0.05). At the 3rd and 6th cycle, women on OCs were sexually cyclic, but the peak improvement of desire, arousal, orgasm, enjoyment, and sexual activity appeared around the 7th day of OC intake (P < 0.05).

CONCLUSION

Reduced hormone-free interval is a new concept in low-dose OC regimens. Moreover, the E2V/DNG multiphasic extended regimen has been found to positively modify the sexuality of users.

Advantages and challenges of oestrogen-free hormonal contraception

BACKGROUND

Not all women tolerate hormonal contraceptives containing oestrogens.

METHODS

The authors selected and evaluated relevant publications on the advantages and challenges of oestrogen-containing and oestrogen-free oral contraceptives obtained from the MEDLINE and Google databases from January 2000 to January 2010. In addition, the reference lists from the obtained publications as well as the authors' clinical experience served as additional sources of information. Emphasis was placed on the common adverse effects and risks associated with oestrogen replacement as well as on the noncontraceptive benefits of combined oral contraceptive pills and progestogen-only pills in the management of menstrual cycle-dependent problems.

FINDINGS

Progestogen-only pills have the potential to abolish many of the common adverse effects associated with oestrogen plus progestogen oral contraceptives and can be used to treat various menstrual cycle-dependent problems. However, only a limited number of clinical comparative studies are available. Progestogen-only pills are associated with a more irregular bleeding pattern than contraceptive pills containing oestrogens, especially during the first few months of therapy. As this is not permanent, adequate counselling is essential in order to prevent unnecessary discontinuation of treatment.

CONCLUSIONS

Progestogen-only pills offer an effective, convenient, and readily reversible method of contraception that is suitable for women with contraindications for oestrogens.

Contraception targets in Mammalian ovarian development

In the human ovary, early in pre-natal life, oocytes are surrounded by pre-granulosa follicular cells to form primordial follicles. These primordial oocytes remain dormant, often for decades, until recruited into the growing pool throughout a woman's adult reproductive years. Activation of follicle growth and subsequent development of growing oocytes in pre-antral follicles are major biological checkpoints that determine an individual females reproductive potential. In the past decade, great strides have been made in the elucidation of the molecular and cellular mechanisms underpinning maintenance of the quiescent primordial follicle pool and initiation and development of follicle growth. Gaining an in-depth knowledge of the intracellular signalling systems that control oocyte preservation and follicle activation has significant implications for improving female reproductive productivity and alleviating infertility. It also has application in domestic animal husbandry, feral animal population control and contraception in women.

Health care providers' knowledge about contraceptive evidence: a barrier to quality family planning care?

BACKGROUND

The underuse of effective contraceptive methods by women at risk for unintended pregnancy is a major factor contributing to the high rate of unintended pregnancy in the United States. As health care providers are important contributors to women's contraceptive use, this study was conducted to assess provider knowledge about contraception.

STUDY DESIGN

Bivariate and multivariate analyses were performed using data collected from a convenience sample of health care providers (physicians, nurse practitioners and physician assistants) at meetings of the professional societies of family medicine and obstetrics and gynecology.

RESULTS

Younger providers were more knowledgeable, as were obstetrician/gynecologists, female providers and providers who provide intrauterine contraception in their practice.

CONCLUSIONS

The lack of consistent and accurate knowledge about contraception among providers has the potential to dramatically affect providers' ability to provide quality contraceptive care for their patients, which could have an impact on their ability to prevent unintended pregnancies.