Marketing environment dynamics and implications for pricing strategies: the case of home health care

This research reviews the factors affecting the pricing or rate schedules of home health care agencies. A large number of factors affect costs and thus rate structures. The major factors include reimbursement structures with accompanying discount structures, administrative burdens, and risks. Channel issues include bargaining power, competition, and size. Staffing issues affect pricing and product through the provider level, productivity, and quality outcomes. Physician and patient issues include quality concerns and choices. These factors are discussed in light of overall marketing strategy and the interaction of pricing with other marketing controllables such as product, place/distribution, and promotion. Economic and accounting principles are also reviewed with consideration to understanding direct and indirect costs in order to enable negotiators to effectively price health care services.

Particle size analysis of concentrated phospholipid microemulsions II. Photon correlation spectroscopy

The solvated droplet size of concentrated water-in-oil (w/o) microemulsions prepared from egg and soy lecithin/water/isopropyl myristate and containing short-chain alcohol cosurfactants has been determined using photon correlation spectroscopy (PCS). The effect of increasing the water volume fraction (from 0.04 to 0.26) on the solvated size of the w/o droplets at 298 K has been investigated at 4 different surfactant/cosurfactant weight ratios (Km of 1:1, 1.5:1, 1.77:1, and 1.94:1); in all cases the total surfactant/cosurfactant concentration was kept constant at 25% w/w. In the case of the microemulsions prepared from egg lecthin, the diffusion coefficients obtained from PCS measurements were corrected for interparticulate interactions using a hard-sphere model that necessitated estimation of the droplet volume fractions, which in the present study were obtained from earlier total intensity light-scattering (TILS) studies performed on the same systems. Once corrected for hard-sphere interactions, the diffusion coefficients were converted to solvated radii using the Stokes-Einstein equation assuming spherical microemulsion droplets. For both egg and soy lecithin systems, no microemulsion droplets were detected at water concentrations less than 9 wt% regardless of the alcohol and Km used, suggesting that at low concentrations of added water, cosolvent systems were formed. At higher water concentrations, however, microemulsion droplets were observed. The changes in droplet size followed the expected trend in that for a fixed Km the size of the microemulsion droplets increased with increasing volume fraction of water. At constant water concentration, droplet size decreased slightly upon increasing Km. Interestingly, only small differences in size were seen upon changing the type of alcohol used. The application of the hard-sphere model to account for interparticulate interactions for the egg lecithin systems indicated that the uncorrected diffusion coefficients underestimated particle size by a factor of slightly less than 2. Reassuringly, the corrected droplet sizes agreed very well with those obtained from our earlier TILS study.

Ovarian response to repeated controlled stimulation in in-vitro fertilization cycles in patients with ovarian endometriosis

In-vitro fertilization (IVF) is an effective infertility treatment for women with endometriosis, but most women need to undergo several cycles of treatment to become pregnant. This case-control study was designed to assess how consistently women with ovarian endometriosis respond to ovarian stimulation in consecutive treatment cycles compared to women with tubal infertility. We compared outcome measures in 40 women with a history of surgically confirmed ovarian endometriosis and 80 women with tubal infertility, all of whom had at least three IVF treatment cycles. The groups were matched for age and early follicular follicle stimulating hormone (FSH) concentration at their first IVF cycle. Outcome measures included number of follicles, number of oocytes, peak oestradiol concentration and number of FSH ampoules required per follicle. Cumulative pregnancy and live birth rates were calculated in both groups. The ovarian endometriosis group had a significantly poorer ovarian response and required significantly more ampoules of FSH per cycle, a difference that became greater with each subsequent cycle. However, cumulative pregnancy (63.3 versus 62.6% by fifth cycle) and live birth (46.8 versus 50.9% by fifth cycle) rates were similar in both groups. In conclusion, despite decreased ovarian response to FSH, ovarian endometriosis does not decrease the chances of successful IVF treatment.

Hormone replacement therapy in postmenopausal women: endometrial hyperplasia and irregular bleeding

BACKGROUND

The decline in circulating oestrogen around the time of the menopause often induces unacceptable symptoms that affect the health and well being of women. Hormone replacement therapy (both unopposed oestrogen and oestrogen and progestogen combinations) is an effective treatment for these symptoms. In women with an intact uterus, unopposed oestrogen may induce endometrial stimulation and increase the risk of endometrial hyperplasia and carcinoma. The addition of progestogen reduces this risk but may cause unacceptable symptoms, bleeding and spotting which can affect adherence to therapy.

OBJECTIVES

The objective of this review is to assess which hormone replacement therapy regimens provide effective protection against the development of endometrial hyperplasia and/or carcinoma with a low rate of abnormal vaginal bleeding.

SEARCH STRATEGY

Electronic searches for relevant randomised controlled trials of the Cochrane Menstrual Disorders and Subfertility Group Register of Trials, MEDLINE, EMBASE, PsychLIT, Current Contents, Biological Abstracts, Social Sciences Index and CINAHL were performed. Attempts were also made to identify trials from citation lists of review articles and drug companies were contacted for unpublished data. In most cases, the corresponding author of each included trial was contacted for additional information.

SELECTION CRITERIA

The inclusion criteria were randomised comparisons of unopposed oestrogen therapy, combined continuous oestrogen-progestogen therapy and sequential oestrogen-progestogen therapy with each other and placebo administered over a minimum treatment period of six months. Trials had to assess which regimen was the most protective against the development of endometrial hyperplasia/carcinoma and/or caused the lowest rate of irregular bleeding.

DATA COLLECTION AND ANALYSIS

Twenty three RCTs were identified and five were excluded. The reviewers assessed the eighteen included studies for quality, extracted the data independently and odds ratios for dichotomous outcomes were estimated. Outcomes analysed included frequency of endometrial hyperplasia or carcinoma, frequency of irregular bleeding and unscheduled biopsies or dilation and curettage, and adherence to therapy.

MAIN RESULTS

Unopposed moderate or high dose oestrogen therapy was associated with a significant increase in rates of endometrial hyperplasia with increasing rates at longer duration of treatment and follow up. Odds ratios ranged from 5.4 (1. 4-20.9) for 6 months of treatment to 16.0 (9.3-27.5) for 36 months of treatment with moderate dose oestrogen (in the PEPI trial, 62% of those who took moderate dose oestrogen had some form of hyperplasia at 36 months compared to 2% of those who took placebo). Irregular bleeding and non adherence to treatment were also significantly more likely under these unopposed oestrogen regimens with greater effects with higher dose therapy. There was no evidence of increased hyperplasia rates, however, with low dose oestrogen. The addition of progestogens, either in continuous combined or sequential regimens, helped to prevent the development of endometrial hyperplasia and improved adherence to therapy (odds ratios of 3.7 for sequential therapy and 6.0 for continuous therapy). Irregular bleeding, however, was more likely under a continuous than a sequential oestrogen-progestogen regimen (OR = 2.3, 95% CI 2.1-2.5) but at longer duration of treatment, continuous therapy was more protective than sequential therapy in preventing endometrial hyperplasia (OR = 0.3, 95% CI 0.1-0.97). There was evidence of a higher incidence of hyperplasia under long cycle sequential therapy (progestogen given every 3 months) compared to monthly sequential therapy (progestogen given every month). No increase in endometrial cancer was seen in any of the treatment groups during the limited duration (maximum of 3 years) of these trials. (ABSTRACT TRUNCATED)

Decreased morbidity and use of hospital services in English HIV-infected individuals with increased uptake of anti-retroviral therapy 1996-1997. National Prospective Monitoring System Steering Group

OBJECTIVE

To investigate the relationship between changing morbidity patterns, the use of hospital services by HIV-infected patients and the uptake of antiretroviral therapy (ART) in England.

DESIGN

Prospective serial cross-sectional analyses based on data collected through the National Prospective Monitoring System (NPMS), a multi-centre prospective monitoring system.

SETTING

HIV-infected patients seen in 10 clinics, five London and five non-London, during the three semesters, 1 January 1996 to 30 June 1997.

MAIN OUTCOME MEASURES

The mean use of hospital services per patient-year, mean new HIV-related opportunistic illnesses per 1000 patient-years and percentage uptake of ART.

RESULTS

The use of inpatient services changed particularly among AIDS patients. The mean number of inpatient days for AIDS patients decreased from 19.7 [95% confidence interval (CI) 13.7-25.7] in 1996 to 11.2 (95% CI 6.1-15.6) per patient-year in 1997. Concurrently the number of new AIDS-defining events decreased significantly from 567 (95% CI 529-607) to 203 (95% CI 183-225) per 1000 patient-years. The overall uptake of ART increased significantly from 33% (95% CI 31-35%) to 50% (95% CI 48-52%), and a switch from mono or dual to triple therapy or quadruple or more therapy was observed. However, by mid-1997 only 29% (95% CI 26-32%) of asymptomatic patients and 51% (95% CI 49-54%) of patients with symptomatic non-AIDS were on ART, compared with 69% (95% CI 66-71%) of AIDS patients.

CONCLUSION

The observed reduction in new AIDS-defining events has led to a reduction in the need for inpatient hospital care and has been associated with an increased uptake of ART, including a switch to triple therapy. All of these factors are likely to have contributed to the observed reduction in mortality among English AIDS patients. As the overall uptake of ART remained relatively low in English centres further improvements can be anticipated. However, the medium to long-term effects of these treatment regimens will need to be closely monitored.

Serologic evidence of human herpesvirus 8 transmission by homosexual but not heterosexual sex

Epidemiologic studies link Kaposi's sarcoma with a sexually transmitted agent. Human herpesvirus 8 (HHV-8) is likely to be that agent, but routes of transmission are poorly described. A seroepidemiologic study was conducted to determine whether HHV-8 is transmitted sexually between heterosexuals. Sera from 2718 patients attending a sexually transmitted disease (STD) clinic were tested for antibodies to HHV-8 and herpes simplex virus type 2 (HSV-2). Information on sex partners in the previous 12 months and past STDs were obtained by questionnaire. Relationships between possible risk factors and HHV-8 infection were assessed by logistic regression. Overall, seroprevalence of HHV-8 was 7.3%. Independent risk factors for HHV-8 in the whole group were homo/bisexuality and birth in Africa and, among homo/bisexual men, a history of syphilis and HSV-2 and human immunodeficiency virus seropositivity. Among heterosexuals there was no evidence for sexual transmission; the only independent risk factor for HHV-8 seropositivity was birth in Africa.

Poor responders to ovulation induction: is proceeding to in-vitro fertilization worthwhile?

A 'poor response' in the context of in-vitro fertilization (IVF) can be defined as failure to produce an adequate number of mature follicles, and/or a peak oestradiol concentration less than a defined minimum. The cut-off points implied in this definition vary between different centres. Many opt to cancel the IVF cycle when their defined minimum concentrations are not reached despite the lack of evidence of improved outcome in subsequent cycles. Patients attending the Oxford Fertility Unit who are 'poor responders' have always been given the option of continuing with treatment. The first cycles of IVF in 124 patients, with normal day 3 follicle stimulating hormone (FSH), who produced less than five follicles within a 2 year period were studied. The patients were divided into three groups according to the number of follicles produced: A (one or two follicles; n = 33), B (three follicles; n = 33) and C (four follicles; n = 58). The three groups were similar in age, day 3 FSH, total gonadotrophin dose, duration of stimulation, peak oestradiol concentration, oocyte yield, fertilization rate and the clinical pregnancy rate. However, group A had a significantly higher oestradiol concentration per follicle (P < 0.001). The clinical pregnancy rate/cycle in the three groups was comparable to our overall rate in the study period (25.5%). This paper suggests that poor responders with a normal day 3 FSH may still achieve a pregnancy rate similar to that of normal responders.

Extremes of body mass do not adversely affect the outcome of superovulation and in-vitro fertilization

The effect of extremes of body mass on ovulation is well recognized by clinicians. However, the effect of obesity and extreme underweight on the outcome of in-vitro fertilization (IVF) cycles has received relatively little attention. In a retrospective nested case-control study we examined the effect of the extremes of body mass index (BMI) on IVF-embryo transfer outcome at a university-based IVF unit. A total of 333 patients were included in the study; 76 obese patients (BMI > 27.9) with 152 controls, and 35 underweight patients (BMI < 19) with 70 controls. The patients were matched with their controls in age +/- 1 year, day 3 follicle stimulating hormone (FSH) concentration, daily dose of gonadotrophin (+/- 37.25 IU), gonadotrophin preparation and the year of treatment. The following parameters were compared between the study and control groups: duration of administration and dose of gonadotrophin, number of follicles aspirated, number of eggs, fertilization rate, number of embryos, serum oestradiol concentration on human chorionic gonadotrophin (HCG) day (peak oestradiol), clinical pregnancy rate, implantation rate, miscarriage rate, and incidence of ovarian hyperstimulation syndrome. Apart from a significantly lower peak oestradiol concentration (P = 0.009) in the obese patients, they and the underweight patients were not significantly different from their normal controls. The extremes of body mass index do not adversely affect the outcome of IVF-embryo transfer treatment. However, the obese patients had lower peak oestradiol concentrations than their normal controls despite receiving similar gonadotrophin doses.

Today's treatments: how do you choose?

OBJECTIVE

To provide a view on how the clinician can select appropriate treatment when managing individual patients with endometriosis.

METHODS

Review of randomized controlled trials and personal experience.

RESULTS

The main determinants of therapy choice are personal experience and patient acceptability. Placebo-controlled trial results support the use of naproxen, dydrogesterone, danazol and leuprolide for pain relief. Laser laparoscopy is more effective than expectant management for pain relief. In direct comparisons, oral contraceptives, Zoladex, danazol, gestrinone, nafarelin and leuprolide have similar efficacies in relieving pain, but have different side-effect profiles. In controlled trials, only laser laparoscopy was shown to improve fertility in minimal/mild disease. The physiological response of bone metabolism to GnRH agonist therapy should be seen in context and the place of add-back regimens understood. The general medical history of the patient must be considered when choosing therapy.

CONCLUSIONS

The clinician must provide the patient with appropriate information on the treatment options to allow her to make an informed choice.

Do gastrointestinal symptoms vary with the menstrual cycle?

This systematic review presents both the physiological and symptom-based studies which have explored gastrointestinal variation across the menstrual cycle. Understanding this variation may be helpful in identifying the origin of pelvic pain, particularly as the symptoms associated with causes, such as endometriosis, also vary across the cycle. One-third of otherwise asymptomatic women may experience gastrointestinal symptoms at the time of menstruation, and almost 50% of women with irritable bowel syndrome report a perimenstrual increase in symptoms.

The use and cost of HIV service provision in England in 1996. National Prospective Monitoring System (NPMS) Steering Group and NPMS Working Party on Costs

OBJECTIVE

The aim of the study was to measure the use and estimate the cost of HIV service provision in England.

DESIGN AND SETTING

Standardised activity and case-severity data were collected prospectively in 10 English HIV clinics (5 London and 5 non-London sites) for the periods 1 January 1996 to 30 June 1996 and 1 July 1996 to 31 December 1996 and linked to unit cost data. In total, 5440 patients with HIV infection attended during the first 6 months and 5708 during the second 6 months in 1996.

MAIN OUTCOME MEASURES AND RESULTS

The mean number of inpatient days per patient-year for patients with AIDS was 19.7 [95% confidence interval (CI): 13.7 to 25.7] for January to June and 20.8 (95% CI: 15.3 to 26.4) for July to December 1996. The mean number of outpatient visits for asymptomatic patients with HIV infection was 14.8 (95% CI: 11.9 to 17.6) and 13.3 (95% CI: 10.8 to 15.7) for the respective periods and 16.1 (95% CI: 13.21 to 18.97) and 15.7 (95% CI: 11.2 to 20.2), respectively, for patients with symptomatic non-AIDS (i.e. symptomatic patients with HIV infection but without AIDS-defining conditions). Substantial centre-to-centre variation was observed, suggesting that many clinics can continue the shift from an inpatient- to an outpatient-based service. Cost estimates per patient-year for HIV service provision for 1996 varied from 4695 Pounds (95% CI: 3769 Pounds to 5648 Pounds) for asymptomatic patients, to 7605 Pounds (95% CI: 6273 Pounds to 8909 Pounds) for symptomatic non-AIDS patients to 20,358 Pounds (95% CI: 17,681 Pounds to 23,206 Pounds) for patients with AIDS.

CONCLUSIONS

Different combinations of antiretroviral therapy affect the cost estimates of HIV service provision differently. Anticipated reduction in inpatient-related activity through the increased use of combination antiretroviral therapy will further shift service provision from an inpatient- to outpatient-based service and reduce costs per patient-year. The extent and duration of such effects are currently unknown. The long term effects of combination treatment on the morbidity and mortality patterns of individuals infected with HIV are also currently unknown, as are their implications on the use and cost of HIV service provision. Multicentre databases like the National Prospective Monitoring System (NPMS) will provide healthcare professionals with information to improve existing services and anticipate the impact of new developments.

Evidence from human oocytes for a genetic bottleneck in an mtDNA disease

We have examined oocytes from a patient with Kearn-Sayre syndrome caused by mtDNA rearrangements. In mtDNA diseases, mutant and wild-type mtDNA frequently coexist in affected individuals (the condition of heteroplasmy). The proportion of mutant mtDNA transmitted from mother to offspring is variable because of a genetic bottleneck, and the "dose" of mutant mtDNA received influences the severity of the phenotype. The feasibility of prenatal diagnosis is critically dependent on the nature and timing of this bottleneck. Significant levels of rearranged mtDNA were detectable in the majority of the patient's oocytes, by use of multiplex PCR, with wide variation, in the levels of mutant and wild-type molecules, between individual oocytes. We also used length variation in a homopolymeric C tract, which is often heteroplasmic in normal controls, to identify founder subpopulations of mtDNAs in this patient's oocytes. We present direct evidence that the number of segregating units (n) is three to five orders of magnitude less than the number of mitochondria in the human female oocyte. In some cases, the best estimate of n may correspond to a single mitochondrion, if it is assumed that intergenerational transmission of mtDNA can be treated as a single sampling event. The bottleneck appears to contribute a major component of the variable transmission from mother to oocyte, in this patient and in a control. That this bottleneck had occurred by the time that oocytes were mature advances the prospects for prenatal diagnosis of mtDNA diseases.

Superovulation with a high gonadotropin dose for in vitro fertilization: is it effective?

PURPOSE

Our purpose was to investigate the effect on the ovarian response of increasing the gonadotropin dose.

METHODS

We analyzed retrospectively the in vitro fertilization data for patients who had two cycles of treatment, with a higher dose in cycle 2. The patients were stratified according to age, ovarian response, and gonadotropin dose in the first cycle. The main outcome measure was the number of follicles, eggs, and embryos and the peak estradiol (E2) level.

RESULTS

The study included 244 patients. Patients in both age groups (n = 118, < or = 33 years; n = 126, > 33 years), low (n = 66) and intermediate (n = 145) responders, and patients who received < 225 IU follicle-stimulating hormone (n = 175) in cycle 1 had a better response in cycle 2. However, the high responders (n = 33) and those who received 225 or 300 IU follicle-stimulating hormone (n = 69) in cycle 1 showed a similar response in both cycles, except for a significantly higher E2 level in cycle 2.

CONCLUSIONS

Our results indicate that exceeding a daily dose of 300 IU is unrewarding.

Uterine cavity assessment prior to in vitro fertilization: comparison of transvaginal scanning, saline contrast hysterosonography and hysteroscopy

A total of 44 patients undergoing in vitro fertilization (IVF) and requiring uterine cavity assessment agreed to have both saline contrast hysterosonography (SCHS) and hysteroscopy. SCHS was performed following a baseline transvaginal scan by injection of saline into the uterine cavity during continuous scanning. Hysteroscopy was performed with a flexible fiberscope with a 3.6-mm outer diameter; 38 of 44 women (86%) underwent both procedures. Hysteroscopy diagnosed intrauterine abnormalities in 16 women. SCHS was in complete agreement in 13 of 16 cases. As a screening test for any cavity abnormality, SCHS had a 87.5% sensitivity, 100% specificity, 100% positive predictive value and 91.6% negative predictive value. In 14 women, an abnormal uterine cavity was apparent on transvaginal scanning (TVS). However, TVS, unlike SCHS, could not (1) confidently diagnose submucosal fibroids in the presence of a uterus with multiple fibroids; (2) distinguish between a hyperplastic endometrium and a large polyp; or (3) differentiate between an arcuate and a septate uterus. In addition, ovarian pathology was diagnosed on TVS in five women: endometrioma (n = 1), complex cysts (n = 2) and polycystic ovaries (n = 2). SCHS is a simple, accurate, well-tolerated procedure that can be performed within a fertility unit, avoiding invasive and expensive diagnostic hysteroscopy. Significant findings can be treated by operative hysteroscopy prior to commencing an IVF treatment cycle.

Assortative sexual mixing in a heterosexual clinic population--a limiting factor in HIV spread?

OBJECTIVE

To assess the degree of sexual mixing in a sexually transmitted disease clinic population stratified by country of birth.

DESIGN

Prospective linked HIV serosurvey incorporating demographic and sexual risk data gathered by a doctor-administered questionnaire.

SETTING

The Department of Genitourinary Medicine at St Thomas' Hospital, London, UK.

SUBJECTS

Fifteen thousand eight hundred and seventy-eight heterosexuals who attended between April 1992 and February 1995.

MAIN OUTCOME MEASURE

The degree of assortative (like-with-like) mixing, after stratification of the population by country of birth, of index patients, their parents and their sexual partners.

RESULTS

Sexual mixing in this population of sexually transmitted disease clinic attenders is highly assortative when the CoB of parents (family origin) of index patients is taken into account.

CONCLUSION

Our findings help to explain the low spread of heterosexual HIV infection in the UK to date, and may help future projections, and health targeting of those at risk. This model can be applied to other mixed population.

Is routine diagnostic laparoscopy for infertility still justified? A pilot study assessing the use of hysterosalpingo-contrast sonography and magnetic resonance imaging

We assessed the value of hysterosalpingo-contrast sonography (HyCoSy) and magnetic resonance imaging (MRI) as alternatives to laparoscopy and dye insufflation with or without hysteroscopy in the investigation of infertility. A total of 19 women had all three procedures, in addition, one became pregnant after HyCoSy alone. The findings were: uterine fibroids (n = 5), minimal-mild endometriosis (n = 4) and moderate-severe endometriosis (n = 3) including one case of bilateral endometriomas, endometrial polyp (n = 1), polycystic ovaries (n = 2), bilateral dermoid cysts (n = 1), haemorrhagic corpus luteal cyst (n = 1) and minimal adhesions (n = 3). At laparoscopy, 31/37 tubes were patent and there was 84% concordance with the tubal patency findings at HyCoSy. The uterine fibroids and ovarian cysts were detected using transvaginal scanning; the endometrial polyp and a congenital uterine anomaly were identified using HyCoSy. These findings were detected using MRI, but in addition the technique distinguished the dermoid cysts from the endometriomas, identified the two other cases of moderate-severe endometriosis, fibroids <2 cm (n = 2) and adenomyosis (n = 5), and interpreted the haemorrhagic corpus luteum as an endometrioma. Our data suggest that women with normal HyCoSy and MRI findings have a normal pelvis and may not need routine surgical investigation.

Gonorrhoea in inner London: results of a cross sectional study

OBJECTIVES

To estimate population based incidence rates of gonorrhoea in an inner London area and examine relations with age, ethnic group, and socioeconomic deprivation.

DESIGN

Cross sectional study.

SETTING

11 departments of genitourinary medicine in south and central London.

SUBJECTS

1978 first episodes of gonorrhoea diagnosed in 1994 and 1995 in residents of 73 electoral wards in the boroughs of Lambeth, Southwark, and Lewisham who attended any of the departments of genitourinary medicine.

MAIN OUTCOME MEASURES

Yearly age, sex, and ethnic group specific rates of gonorrhoea per 100,000 population aged 15-59 years; rate ratios for the effects of age and ethnic group on gonorrhoea rates in women and men before and after adjustment for confounding factors.

RESULTS

Overall incidence rates of gonorrhoea in residents of Lambeth, Southwark, and Lewisham were 138.3 cases yearly per 100,000 women and 291.9 cases yearly per 100,000 men aged 15-59 years. At all ages gonorrhoea rates were higher in non-white minority ethnic groups. Rate ratios for the effect of age adjusted for ethnic group and underprivilege were 15.2 (95% confidence interval 11.6 to 19.7) for women and 2.0 (1.7 to 2.5) for men aged 15-19 years compared with those over 30. After deprivation score and age were taken into account, women from black minority groups were 10.5 (8.6 to 12.8) times as likely and men 11.0 (9.7 to 12.6) times as likely as white people to experience gonorrhoea.

CONCLUSIONS

Gonorrhoea rates in Lambeth, Southwark, and Lewisham in 1994-5 were six to seven times higher than for England and Wales one year earlier. The presentation of national trends thus hides the disproportionate contribution of ongoing endemic transmission in the study area. Teenage women and young adult men, particularly those from black minority ethnic groups, are the most heavily affected, even when socioeconomic underprivilege is taken into account. There is urgent need for resources for culturally appropriate research and effective intervention to prevent gonococcal infections and their long term sequelae in this population.

Infertility treatment and multiple birth rates in Britain, 1938-94

Trends in multiple birth rates are thought to have been substantially affected by subfertility treatments in the last 25 years, but there are few quantitative assessments of this. This paper examines trends in twin and higher multiple birth rates separately in Scotland, England and Wales and compares their course with corresponding multiple birth rates in the Oxford Record Linkage Study area, where the proportions following subfertility treatment are documented. National data on prescriptions for subfertility treatments reinforce the view that they have had a major effect on the trends, and currently perhaps 60% of triplet and higher order births and 15% of twins follow their use in Britain.