Kate Weaver

Interaction between broad-spectrum antibiotics and the combined oral contraceptive pill: A literature review

There is considerable variation in opinion about the importance of drug interactions between the combined oral contraceptive pill (COCP) and broad-spectrum antibiotics. Clinical practice varies widely, especially between doctors in Europe and those in the US. Rifampicin and griseofulvin induce hepatic enzymes and do appear to have a genuine interaction with the COCP, leading to reduced efficacy. The situation with the broad-spectrum antibiotics is less clear. There are relatively few prospective studies of the pharmacokinetics of concurrent COCP and antibiotic use and few, if any, demonstrate a convincing basis for any reduced contraceptive efficacy. There is evidence, however, that variable contraceptive steroid handling could make some women, at some times, more susceptible to COCP failure. Given the serious consequences of unwanted pregnancy, the cautious approach of using additional or alternative contraception during short courses of broad-spectrum antibiotics and the initial weeks of long-term antibiotic administration may be justified to safeguard the few unidentifiable women who may be at risk. Conflicting opinion and advice is potentially confusing to both professionals and patients, and instructions for additional precautions during and after concurrent COCP and antibiotic use are complicated. Many women are ignorant of, or confused about, the circumstances that can cause OC to fail. Health professionals who prescribe the COCP must continue to strive to educate women about the mode of action and about the times when there is the greatest danger of failure. Professionals who feel that concurrent antibiotic use represents a real threat to contraceptive efficacy of the COCP should be prepared to present the advice for additional contraceptive precautions in a simple and consistent way, backed up with written information and reinforced at regular intervals.

Does a short cessation of HRT decrease mammographic density

BACKGROUND Hormone replacement therapy (HRT) is known to increase breast density, thus decreasing the sensitivity of cancer screening by mammography. Some authors recommend short cessation of HRT before mammography, but evidence showing the effect of such short cessation is limited. The purpose of this study is to examine whether a short cessation of HRT changes mammographic density. METHODS Forty-eight women taking HRT agreed to have mammograms taken before and after stopping HRT for 4 weeks. Mammographic density was measured by Wolfes four-point classification, six-categorical visual scale and two different computer methods (interactive-thresholding and SMF). Density values of mammography before and after the cessation of HRT were compared using Wilcoxon signed-rank test for categorical variables and paired t-test for continuous variables. Changes in breast pain and tenderness during mammography, radiation dose, compression force, and breast thickness were also recorded. RESULTS No significant changes in mammographic density were observed by either visual or computer methods. There were no significant changes in breast pain or in tenderness on mammograms before and after the months cessation of HRT. Radiographic measurements were not significantly altered by the 4-week cessation of HRT. CONCLUSION In this screening population, a 4-week cessation of HRT before mammograms did not significantly alter mammographic density.

Prenatal Tests: The Facts

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A utility maximising model for evaluation of health care programmes. Health Serv Res 1972; 7: 118–133. 14 Kind P, Dolan P, Gudex C, Williams A. Practical and methodological issues in the development of the EuroQol: the York experience. Adv Med Sociol 1994; 5: 219–253. 15 EuroQol. EuroQol – a new facility for the measurement of healthrelated quality of life. Health Policy 1990; 16: 199–208. 16 Dolan, P, Gudex, C, Kind, P, Williams, A. A Social Tariff for EuroQol: Results from a UK General Population Survey (Discussion Paper No.138). York, UK: University of York, 1995. 17 Ware J, Sherbourne C. The SF-36 short-form health status survey 1. Conceptual framework and item selection. Med Care 1992; 30: 473–483. 18 Fryback DG, Lawrence WF, Martin PA, Klein R, Klein B. Predicting quality of well-being scores from the SF-36: results from the Beaver Dam Health Outcomes Study. Med Decis Making 1997; 17: 1–9. 19 Veenstra M, Pettersen KI, Rollag A, Stavem K. Association of changes in health-related quality of life in coronary heart disease with coronary procedures and sociodemographic characteristics. Health Qual Life Outcomes 2004; 2: 56. 20 Brazier J. The SF-36 health survey questionnaire – a tool for economists. Health Econ 1993; 2: 213–216. 21 Brazier J, Roberts J, Deverill M. The estimation of a preference-based measure of health from the SF-36. J Health Econ 2002; 21: 271–292. 22 Donaldson C, Atkinson A, Bond J. Should QALYs be programme specific? J Health Econ 1988; 7: 239–257. 23 Patient-Reported Outcome and Quality of Life (PROQOLID) Instruments Database. Lyon, France: MAPI Research Institute. http://www.proqolid.org [Accessed 6 February 2006]. 24 Sculpher MJ, Manca A, Abbott J, Fountain J, Garry R. Costeffectiveness analysis of laparoscopic hysterectomy compared with standard hysterectomy: results from a randomised controlled trial. BMJ 2004; 328: 134–140. 25 Ratcliffe J, Ryan M, Tucker J. The costs of alternative types of routine antenatal care for low risk women: shared care vs care by general practitioners and community midwifes. J Health Serv Res Policy 1996; 11: 135–140. 26 Ryan M. Should government fund assisted reproductive techniques? A study using willingness to pay. Appl Econ 1997; 29: 849. 27 Whynes DK, Frew E, Wolstenholme JL. A comparison of two methods for eliciting contingent valuations of colorectal cancer screening. J Health Econ 2003; 22: 555–574. 28 Zethraeus N. Willingness to pay for hormone replacement therapy. Health Econ 1999; 7: 31–38. 29 Mitchell RC, Carson RT. Using Surveys to Value Public Goods: The Contingent Valuation Method. Washington, DC: Resources for the Future, 1989. 30 Hundley V, Ryan M, Graham W. Assessing women’s preferences for intrapartum care. Birth 2001; 28: 254–263. 31 Ryan M, Donaldson C. Assessing the costs of assisted reproductive techniques. Br J Obstet Gynaecol 1996; 103: 198–201. 32 Ryan M, Hughes J. Using conjoint analysis to value surgical versus medical management of miscarriage. Health Econ 1997; 6: 261–273. 33 Ryan M. Using conjoint analysis to go beyond health outcomes: an application in in-vitro fertilisation. Soc Sci Med 1999; 48: 535–546. 34 San Miguel F, Ryan M, McIntosh E. Demonstrating the use of conjoint analysis in health economics: an application to menorrhagia. Appl Econ 2000; 32: 823–833. 35 Ryan M, Gerard K. Using choice experiments to value health care programmes: where are we and where should we go? Paper presented at the 3rd International Health Economics Association Conference, University of York, York, UK, July 2001. 36 Kleinman L, McIntosh E, Ryan M, Schimer J, Crawley J, Locke GR, et al. Willingness to pay for complete symptom relief of gastroesophogeal reflux disease. Arch Intern Med 2002; 162: 1361–1366. 37 Ryan M, McIntosh E, Shackley P. Using conjoint analysis to assess consumer preferences in primary care: an application to the patient health card. 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Oral contraceptives and the risk of breast cancer in BRCA1 and BRCA2 mutation carriers. Narod SA, Dube MP, Klijn J, et al. J Natl Cancer Inst 2002; 94(23): 1773-1779.

Contraceptive advice for the woman with a strong family history of breast and ovarian cancer is a difficult area. Some of these women carry known genetic mutations (BRCA1 and BRCA2) predisposing to breast and ovarian cancer. It remains unclear whether contraceptive steroids further increase their cancer risks. A recent international case-control study looked at the risks of breast cancer among 2622 women with these mutations. It was found that women with the BRCA1 gene mutation had a slightly higher risk of early-onset breast cancer if they had ever used oral contraception. The increased risk related particularly to women who had used oral contraception for more than 5 years, or at a younger age, or before 1975. Women with the BRCA2 gene mutation appeared not to increase their breast cancer risk by using oral contraception, however far fewer of these women were studied. This well-designed study adds to our knowledge in this difficult area but frustratingly did not look specifically at the oestrogen/progestogen content of oral contraceptives used by the women. Any evidence of increased breast cancer risk must be weighed against growing evidence that combined oral contraception helps protect against ovarian cancer in these high-risk women.

A review of bone mineral density scans referred by a community-based menopause clinic in 1997

Osteoporosis is a growing public health issue for the UKs ageing population. Many older women want know if they are at risk of osteoporosis and if preventive treatment, particularly in the form of hormone replacement therapy (HRT), would be advisable. This results in many women being referred for bone mineral density (BMD) scanning, whether or not they have recognised risk factors for osteoporosis. We present the results of a review of 228 referrals for BMD scan from a community-based menopause clinic. The results are categorised by the indications for the scan. The implications for the future of BMD investigations are considered in the light of ongoing discussion about population screening.

Preventing Cervical Cancer. What Every Woman Should Know

ethnographic research. Ethnographers Tool Kit (Vol. 1). Walnut Creek, CA: Altamira Press, 1998. 21 Sallis JF, Owen N. Ecological models. In: Glanz K, Lewis FM, Rimer BK (eds), Health Behavior and Health Education. Theory, Research, and Practice (2nd edn). San Francisco, CA: Jossey-Bass, Inc., 1997; 403–424. 22 Carey JW, Wenzel PH, Reilly C, Sheridan J, Steinberg JM, Harbison KG. CDC EZ-Text: Software for Collection, Management and Analysis of Semi-structured Qualitative Databases (Version 3.06). Atlanta, GA: Conwal Incorporated for the Centers for Disease Control and Prevention, 1998. 23 World Health Organization (WHO). Medical Eligibility Criteria for Contraceptive Use (3rd edn). Geneva, Switzerland: WHO, 2004. 24 World Health Organization (WHO). Selected Practice Recommendations for Contraceptive Use (2nd edn). Geneva, Switzerland: WHO, 2004. 25 Bruce J. Fundamental elements of quality of care: a simple framework. Stud Fam Plann 1990; 21: 61–91. 26 Ndhlovu L. Quality of Care in Family Planning Service Delivery in Kenya: Clients’ and Providers’ Perspectives. Nairobi, Kenya: Population Council, Africa Operations Research and Technical Assistance Project, 1995. 27 Kaida A, Kipp W, Hessel P, Konde-Lule J. Male participation in family planning: results from a qualitative study in Mpigi District, Uganda. J Biosoc Sci 2005; 37: 269–286.

The Opposite of Chocolate

women undergoing surgical abortion under local anaesthesia and the effect on acceptability. In addition, there is a need to assess the cost implications of this approach in comparison to other methods. A randomised controlled trial conducted in Aberdeen compared sublingual to vaginal administration of misoprostol 400 μg in the context of cervical priming prior to surgical abortion and showed similar efficacy and good patient acceptability.15 The sublingual route was used in this study to allow self-administration at home prior to hospital admission, thus minimising the duration of time needed to be in hospital and to allow an optimal priming interval prior to surgery.

The Reproduction Revolution: A Christian Appraisal of Sexuality, Reproductive Technologies and the Family

women undergoing surgical abortion under local anaesthesia and the effect on acceptability. In addition, there is a need to assess the cost implications of this approach in comparison to other methods. A randomised controlled trial conducted in Aberdeen compared sublingual to vaginal administration of misoprostol 400 μg in the context of cervical priming prior to surgical abortion and showed similar efficacy and good patient acceptability.15 The sublingual route was used in this study to allow self-administration at home prior to hospital admission, thus minimising the duration of time needed to be in hospital and to allow an optimal priming interval prior to surgery.

Drugs for Pregnant and Lactating Women

undergone a TOP and the question was therefore more concrete. It is also possible that the more positive reaction in the present study was coloured by the general satisfaction women felt with the service they received, and relief that the TOP had been performed. A high level of satisfaction with the service was evident, with many women choosing to comment on this. Whilst it is common practice for questionnaires to incorporate a ‘catch-all’ question, it is unusual for such a high proportion of respondents to provide feedback. Whilst there were some negative comments, the majority were positive, particularly regarding the care the women received from the clinic staff. It is possible that some women anticipated a negative reaction from the clinic staff, especially if they faced an unsympathetic or unco-operative health professional in the first instance. Other studies5,14,19 have similarly reported that young women found staff at the TOP clinic to be very supportive.

Attitudes towards pelvic examination and chaperones: a questionnaire survey of patients and providers. Fiddes P, Scott A, Fletcher J, et al. Contraception 2003; 67: 313-317

Recent large randomised trials have made us re-evaluate the indications for hormone replacement therapy (HRT) and have increased interest in prescribing non-hormonal alternatives for vasomotor symptoms. These two studies published in the same journal raise interesting concepts relating to menopausal symptoms. The cross-sectional study by Whiteman and colleagues suggests that lifestyle factors such as smoking and a high body mass index (BMI) may predispose a woman towards more severe or frequent hot flushes. Over 1000 US women aged between 40 and 60 years participated in a mailing survey entitled ‘Study of Women’s Health in Midlife ’. Detailed hot flush and smoking histories were obtained together with extensive demographic information. BMI was calculated from selfreported height and weight at the time of the survey. Current smokers had 1.9 times the odds of never smokers for reporting moderate to severe hot flushes (95% CI 1.3–2.9). High BMI (>30 kg/m2) was also associated with an increased risk of moderate to severe vasomotor symptoms with an adjusted odds ratio of 2.1 (95% CI 1.5–3.0) compared to women with low BMI (<24 kg/m2). The cross-sectional nature of this study limits the conclusions that can be drawn and the authors emphasise the need for prospective studies in this field. However, smoking and high BMI are both potentially modifiable risk factors and this study may give the clinician some authority to persuade women to improve their general lifestyle. Guttuso and colleagues evaluated the role of the anti-epileptic agent, gabapentin, in the treatment of menopausal symptoms in a small, 12-week randomised trial. Gabapentin at a dose of 900 mg/day was associated with a 45% reduction in hot flush frequency and a 54% reduction in hot flush composite score (frequency and severity combined), compared with 29% and 31% reductions, respectively, for placebo. A total of 54 women completed the double-blind study, although four women (13%) withdrew from the gabapentin group and half the women in that group reported at least one adverse effect. Side effects included drowsiness and dizziness, although the authors claim these effects can be minimised by gradual titration of the initial dose. The mode of action of gabapentin in reducing hot flushes is unknown, although it is known to have an anxiolytic effect and the potentially sedative role may have reduced perception of night sweats. We need more agents to treat menopausal symptoms in women with contraindications to HRT or who feel that they have taken HRT in the long term and desire an effective alternative. Gabapentin shows good potential in this regard. Ongoing studies will provide further good quality clinical data and gabapentin should probably be used only with caution for this indication.