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Biomedical subjects

W Ledger

Publications and source records attributed to W Ledger.

At least 19 recordsLinked to original sources
PubMed2006

Implementation of the NICE guideline - recommendations from the British Fertility Society for national criteria for NHS funding of assisted conception.

Assisted conception providers in England were surveyed to establish the uptake of NICE guideline for infertility particularly in respect of assisted conception and the criteria used to accept patients for NHS funded treatment. Detailed information on selection criteria was obtained from a group of commissioning consortia at an advanced stage in their arrangements. While there was an overall increase in the number of NHS IVF cycles purchased in England, implementation is stalled at one fresh cycle in the vast majority of Primary Care Trusts (PCTs). There is little consensus about the criteria used for acceptance into an NHS programme. This is particularly so in respect of social criteria which are often arbitrary and used as a rationing tool. This information complements that provided by the survey of Primary Care Trusts performed in March 2005 by the All Party Parliamentary Group on Infertility (APPGI) in partnership with the National Infertility Awareness Campaign (NIAC) which together provide a basis for recommendations for NHS funding. The recommendations presented should be applied across England and Wales to ensure consistency, fairness and equity of access.

Adult↗
PubMed2002

Serum inhibins, estradiol, progesterone and FSH in surgical menopause: a demonstration of ovarian pituitary feedback loop in women.

BACKGROUND: The objective of this study was to confirm the source and study the acute changes and relationship between inhibins and FSH at surgical menopause. METHODS: Regularly cycling women (42-47 years; n = 10) undergoing bilateral oophorectomy for non-ovarian pathology were recruited for this study. One blood sample was taken before surgery and after removal of the ovaries, samples were taken every 15 min up to 1 h, hourly up to 6 h, after 12 h and daily during the hospital admission (3 days). RESULTS: There were five women in the follicular phase and five women in the luteal phase of the cycle. For women in both phases, levels of inhibin A, inhibin B, estradiol (E(2)) and progesterone decreased after the removal of the ovaries. Serum FSH levels started to rise after 12 h in both follicular and luteal phase women after the surgical menopause. Correlation analysis showed that inhibin A and E(2) were significantly negatively correlated in both phases with FSH concentration. Inhibin B had a negative correlation in the follicular phase and progesterone had a negative correlation in the luteal phase. CONCLUSIONS: This study showed that ovarian inhibin A and B were cleared from the circulation within 12 h of oophorectomy, whereas E(2) and progesterone remain in the circulation for longer. Negative correlation between FSH, inhibin A and inhibin B suggests that inhibins may contribute to the observed early rise in FSH after the surgical menopause.

Adult↗
PubMed2001

Cost-effectiveness modelling of recombinant FSH versus urinary FSH in assisted reproduction techniques in the UK.

BACKGROUND: The purpose of this study was to undertake an economic evaluation to compare the cost-effectiveness of recombinant (r)FSH with urinary (u)FSH for attaining clinical pregnancy with assisted reproduction. METHODS: Mathematical modelling was utilized incorporating a Markovian decision framework and a Monte Carlo simulation. Statistical representations of recurrent events over time were incorporated into a decision analysis involving fresh and frozen cycles in any sequence (after the first fresh embryo transfer cycle) over three successive assisted reproduction attempts. The mean values of transition probabilities were derived from randomized controlled clinical trials and published reports. The distributions of these transition probabilities were agreed upon by a panel of experts. Cost data for procedures and drugs were derived and validated according to the perspectives of the National Health Service and private clinics in the UK. RESULTS: The study involved 5000 Monte-Carlo simulations of treatment on a Markov cohort of 100 000 patients. The total number of pregnancies attained was significantly higher in the rFSH (40 575) compared with the uFSH (37 358) group. The cost per successful pregnancy was significantly lower for rFSH (5906 pounds sterling) compared with uFSH (6060 pounds sterling) and overall, fewer cycles of treatment were required with rFSH to achieve an ongoing pregnancy. The incremental cost-effectiveness ratio is 4148 pounds sterling for each additional clinical pregnancy with rFSH. CONCLUSIONS: In addition to the increased effectiveness of rFSH in ART, this study demonstrated that it is more cost-effective and more efficient than uFSH in attaining an ongoing pregnancy.

Cost-Benefit Analysis↗
PubMed2001

Serum activin A and follistatin in disorders of spermatogenesis in men.

OBJECTIVE: Inhibin, activin and follistatin are glycoprotein hormones produced by the gonads. Recent studies have shown that inhibin B is the predominant form of inhibin in the circulation in men. The objective of this study was to investigate circulating levels of activin A and follistatin in disorders of spermatogenesis in men and their relationship with FSH and inhibin B. DESIGN AND METHOD: Serum from five different groups of men was prospectively collected and stored at -20 degrees C. The groups were men with: (i) proven fertility (controls) (n=20), (ii) primary testicular failure (n=15), (iii) obstructive azoospermia (n=10), (iv) oligospermia (n=10) and (v) miscellaneous sperm dysfunction (n=40). WHO criteria (1992) were used for semen characterisation. Serum concentrations of 'total' activin A, follistatin, FSH and inhibin B were measured using specific two-site enzyme immunoassays. RESULTS: Activin A levels were significantly lower than in the controls in the obstructive azoospermia group and higher in the miscellaneous sperm dysfunction group. Serum follistatin levels did not significantly vary in any group compared with the controls. Circulating levels of FSH were higher than in the controls in the primary testicular failure and obstructive azoospermic group. Levels of inhibin B were lower than in the controls in all disorders of spermatogenesis studied. CONCLUSION: This study demonstrates that activin A and follistatin are in the circulation in males and activin A levels are significantly lower in obstructive azoospermia and higher in miscellaneous sperm dysfunction than in controls. The mechanism involved in altering the levels of activin A in these conditions is not clear. However, high follistatin:activin A molar ratios (>2.5) in all groups suggests that all activin A in the circulation is bound to follistatin in males.

Activins↗
PubMed2001

Characterization of adenylyl cyclases in cultured human granulosa cells.

Granulosa cells play an essential role in follicular development and formation of corpora lutea. Many functions of granulosa-lutein cells are controlled by activation of G protein-coupled receptors and the formation of cyclic AMP (cAMP) by adenylyl cyclase. There are at least nine mammalian adenylyl cyclase isoenzymes, which show different sensitivities towards other signalling systems. The aim of this study was to identify the types of adenylyl cyclase present in human granulosa cells and to investigate its functional regulation by G proteins, calcium and the protein kinase C and A pathways. Granulosa cells were obtained from women undergoing IVF. The cells were maintained in primary culture and they consistently expressed mRNA coding for adenylyl cyclase I, III, VI, VII and IX. The signals for adenylyl cyclase V and VIII were more variable among patients and there was no signal for adenylyl cyclase II. The expression of multiple adenylyl cyclase proteins was confirmed by immunochemistry with subtype-specific antibodies. The formation of cAMP in cultured cells was stimulated many times by hCG (EC(50) value 4.2 iu ml(-1)) and by prostaglandin E(2) (PGE(2); EC(50) = 0.75 micromol l(-1)) in a concentration-dependent manner, thus confirming the presence of receptors coupled positively to G(s). The diterpene forskolin, which stimulates all isoforms of adenylyl cyclase except for adenylyl cyclase IX, increased cAMP formation to higher levels than hCG or PGE(2). The strong stimulation by forskolin indicates that adenylyl cyclase IX is unlikely to be the major source of cyclase activity in these cells. Basal and forskolin- or PGE(2)-stimulated adenylyl cyclase activity was amplified 1.5-2.0 times by phorbol-12,13-dibutyrate, indicating that protein kinase C-sensitive enzymes (for example, adenylyl cyclase types IV, V, VI or VII) may be active in the cells. In contrast, hCG-stimulated activity was inhibited (76 +/- 6%) by phorbol ester. Stimulation of G(i) with the alpha-adrenoceptor agonist clonidine inhibited hCG-induced cyclase activity. This finding indicates that adenylyl cyclase II and IV subtypes, which are stimulated by betagamma subunits released from G(i), are not predominant. Increases in intracellular free calcium concentrations by the ionophore A23187, the calcium-ATPase inhibitor thapsigargin or by fluprostenol, a selective prostanoid FP receptor agonist, which is known to open calcium channels in granulosa cells, or removal of calcium by EGTA, had no significant effects on basal or forskolin-stimulated formation of cAMP. These results indicate that subtypes adenylyl cyclase I, III and VIII, which are activated by calcium, and adenylyl cyclase V and VI, which are inhibited by calcium, are not dominant isoforms in granulosa-lutein cells. The protein kinase A inhibitor H89 had no effects on formation of cAMP; this finding rules out the involvement of adenylyl cyclase V and VI subtypes, which are subjected to negative feedback by protein kinase A. These results indicate that adenylyl cyclase VII is the dominant functional isoenzyme in human granulosa-lutein cells.

Adenylyl Cyclases↗
PubMed2000

Induction of ovulation in women undergoing assisted reproductive techniques: recombinant human FSH (follitropin alpha) versus highly purified urinary FSH (urofollitropin HP).

This multicentre, open, randomized, study compared the efficacy and safety of recombinant follicle stimulating hormone (rFSH; follitropin alpha) with highly purified urinary human FSH (uFSH; urofollitropin HP) in women undergoing ovulation induction for assisted reproductive techniques. Following long down-regulation with buserelin, patients received two ampoules of 75 IU (150 IU) s.c. rFSH or highly purified uFSH for 6 days, after which the dose could be increased until they fulfilled the criteria for human chorionic gonadotrophin (HCG) administration. Of 168 patients recruited, 155 received at least one dose of FSH, and 137 received HCG [68: rFSH (85%); 69: uFSH (92%)]. Following oocyte retrieval and fertilization, up to three embryos were replaced/patient and luteal support was given. The mean number of oocytes retrieved/patient was 10.2 +/- 6.0 for rFSH patients compared with 10.8 +/- 6.1 in the uFSH group (not significant). There was a trend towards fewer ampoules used (22.3 +/- 6.5 versus 24.3 +/- 6.5), higher pregnancy (44.3 versus 41.4%) and live birth rates (33.8 versus 26.7%), as well as a lower miscarriage rate (0.0 versus 16.7%) in favour of rFSH. However, no significant differences in efficacy parameters were recorded. Ovarian hyperstimulation syndrome occurred in 8.6% and 7.9% of rFSH and uFSH patients respectively. In conclusion, this protocol was effective in inducing multiple follicular development and high numbers of oocytes were retrieved with both drugs.

Adolescent↗
PubMed2000

Serum inhibin A and activin A are elevated prior to the onset of pre-eclampsia.

Serum inhibin A and activin A concentrations increase in pre-eclampsia. We investigated the time courses of the changes in relation to the onset of the maternal syndrome and if their measurement could be useful for clinical prediction particularly in relation to early onset disease, the most severe of the clinical presentations. Serial samples were taken from 1496 healthy nulliparae. Changes in activin A and inhibin A were analysed in women with: early onset pre-eclampsia (n = 11), pre-eclampsia delivering at 34-36 weeks (n = 14), term pre-eclampsia (n = 25) and gestational hypertension (n = 25); and in a subset with uncomplicated pregnancies (n = 25). Serum inhibin A and activin A were increased in all groups prior to pre-eclampsia, before 20 weeks in those with early onset pre-eclampsia. Screening efficacy was determined at 15-19 and 21-25 weeks in all women who developed pre-eclampsia (n = 70) and randomly selected controls (n = 240). Predictive sensitivities were low (16-59%) but much better for early onset pre-eclampsia: 67 and 44% at 15-19 weeks and 89 and 89% at 21-25 weeks for inhibin A and activin A respectively. Hence, serum inhibin A and activin A concentrations increase before the onset of pre-eclampsia at gestational ages that depend on when pre-eclampsia develops. On their own such measures are unlikely to prove efficient for screening.

Activins↗
PubMed2000

Inhibin expression in normal and pre-eclamptic placental tissue.

Serum inhibin levels increase during normal pregnancy, but are significantly higher in patients with pre-eclampsia. The aim of this study was to demonstrate possible increased expression of inhibin within the placentas of women with pre-eclampsia compared with non-pre-eclamptic controls. Cellular expression of inhibin alpha and beta A subunits was studied using immunohistochemistry on formalin-fixed, paraffin-embedded placental sections from cases of pre-eclampsia (n = 23) and gestational age-matched non-pre-eclamptic controls (n = 16). Immunohistochemistry was performed using monoclonal antibodies against inhibin alpha and beta A subunits by the indirect immunoperoxidase technique. Intensity of staining was graded by a semiquantitative scoring method. Differences in distribution and intensity of staining between control and pre-eclamptic placentas were analyzed using a nonparametric Mann-Whitney U test. Staining for both inhibin alpha and beta A was predominantly confined to the cytoplasm of syncytiotrophoblast, with weak expression within intermediate trophoblast. The intensity of staining for inhibin alpha was significantly greater in the syncytiotrophoblast of pre-eclamptic patients (mean staining intensity controls = 0.97, disease = 1.87; p < 0.001). Inhibin beta A staining was generally stronger than for the alpha subunit, and was also significantly increased in pre-eclamptic patients compared with controls (mean controls = 1.72, disease 2.19; p < 0.05). This is the first evidence for increased placental inhibin presence in pre-eclampsia, suggesting increased inhibin production within the placenta, a finding that could account for increased serum inhibin levels in pre-eclampsia.

Cytoplasm↗
PubMed2000

Detection of chlamydial antigenic material in ovarian, prostatic, ectopic pregnancy and semen samples of culture-negative subjects.

PROBLEM: The pathogenesis of long-term sequelae in Chlamydia trachomatis infection is poorly understood. While serology indicates previous chlamydial infection, culture studies are frequently negative. We wanted to know whether in chronic cases the bacterium is absent or persists in a dormant state where it evades detection. METHODS OF STUDY: Using immunoperoxidase (IP) staining and in situ hybridization (ISH), we examined tissues of culture-negative subjects. Ovarian biopsy specimens from 19 culture-negative women with pelvic adhesions and/or tubal infertility were analyzed by both methods. Samples of prostates from 10 culture-negative men undergoing prostatectomy for benign hypertrophy, two sets of semen samples from culture-negative sexual partners of 28 women with PID and/or bacterial vaginosis (BV), and ten endometrium-tube sample-pairs from ectopic pregnancies (EPs) were examined by IP only. RESULTS: Seven of the nineteen ovarian specimens tested positive for Chlamydia antigen or deoxyribonucleic acid (DNA) (36%). Of the 10 hypertrophic prostates examined, 4 (40%) were positive. Of the 28 semen samples examined, 10 (35%) tested positive. Tissue samples of 3 cases of EP were positive by IP. CONCLUSIONS: 1. C. trachomatis antigen and nucleic acid can be frequently demonstrated in asymptomatic, culture-negative men and women with chronic infection. 2. Chlamydia antigens may have an etiologic role in benign prostate hypertrophy and EP. 3. Antigenic material may be sexually transmissible. 4. IP and ISH identify temporarily inactive bacteria that may continue to act as immunostimulants and potentially reactivate as Chlamydia infection.

Adult↗
PubMed1999

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.

Abortion, Spontaneous↗
PubMed1999

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.

Adult↗
PubMed1998

Incidence of postpartum endomyometritis following single-dose antibiotic prophylaxis with either ampicillin/sulbactam, cefazolin, or cefotetan in high-risk cesarean section patients.

OBJECTIVE: To assess the efficacy of single-dose antibiotic prophylaxis against postpartum endomyometritis in high-risk cesarean section patients. DESIGN: Patients were administered one of three single-dose antibiotic regimens following umbilical cord clamping after cesarean section delivery. SETTING: Prospective randomized trial at a university-based hospital. PATIENTS: The study evaluated 293 consenting women undergoing cesarean section who had either experienced labor for a duration of > or = 6 hr or rupture of amniotic membranes. MAIN OUTCOME MEASURES: Development of postpartum endomyometritis. RESULTS: The incidence of postpartum endomyometritis was 7/95 (7.4%) following the ampicillin/sulbactam regimen, 14/98 (14.3%) after the cefazolin regimen, and 11/99 (11.1%) after the cefotetan regimen. There was no significant difference in postpartum infection among the three study arms. In addition, the incidence of endomyometritis in the three single-dose study arms was not higher than previously noted in studies where three doses of antibiotic were administered. CONCLUSION: Single-dose antibiotic prophylaxis should replace the standard triple-dose therapy for uninfected women undergoing cesarean section who are at risk for postoperative endomyometritis. Ampicillin/sulbactam, cefazolin, and cefotetan are all reasonable antibiotic choices for single-dose therapy.

Adult↗
PubMed1998

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.

Adult↗
PubMed1997

Gonadotropic control of secretion of dimeric inhibins and activin A by human granulosa-luteal cells in vitro.

PURPOSE: It is well established that human granulosa cells and luteal cells express inhibin/activin subunit protein and secrete immunoreactive inhibin. The gonadotropic control of secretion of different molecular forms of inhibin and activin A by granulosa-luteal cells (G-LCs) was investigated using recently developed specific enzyme immunoassays (EIAs). METHODS: Granulosa-luteal cells obtained at IVF egg pickup were cultured in a serum-free medium at 37 degrees C in a water-saturated incubator with 5% CO2 for up to 5 days. Experiments with varying concentrations of human FSH, hLH, and hCG were carried out. RESULTS: FSH raised the secretion of inhibin A and pro-alpha C-containing inhibins after 24 and 48 hr in culture. Inhibin B was raised after 24 hr and activin A was raised after 48 hr of FSH treatment. LH treatment for 24 hr stimulated inhibin A, inhibin B, pro-alpha C, and activin A. hCG stimulated G-LC secretion of inhibin A after 48 hr and pro-alpha C after 24 hr. Paradoxically, inhibin B secretion was inhibited by 1 and 10 ng/ml hCG after 48 hr. Activin A was stimulated by hCG after 24 and 48 hr of incubation. G-LC secretion of estradiol and progesterone was also stimulated significantly by LH and hCG. CONCLUSIONS: Secretion of dimeric inhibins and activin A is controlled differentially by gonadotropins.

Activins↗
PubMed1997

Inhibin A and activin A in the first trimester of human pregnancy.

Recent studies show that high concentrations of inhibin A and activin A are present in the maternal serum throughout human pregnancy. The aim of this study was to determine whether the corpus luteum produces significant quantities of inhibin A and activin A during the first trimester of pregnancy. This prospective study examined two groups of women who had blood samples taken from 5-12 weeks gestation. One group consisted of 14 women with donor egg pregnancies (8 singletons and 6 multiples) who did not have corpora lutea, and the other group consisted 5 women with spontaneous pregnancies who had corpora lutea. Inhibin A and activin A were measured at weekly intervals using specific enzyme immunoassays. All pregnancies progressed to term, with healthy babies being delivered. Maternal serum concentrations of inhibin A significantly increased throughout the study period in the donor egg pregnancies (P < 0.001) and the control pregnancies (P < 0.001). Circulating concentrations of activin A also increased significantly in both the spontaneous and donor egg pregnancies (P < 0.001) during the study period. However, the concentrations of inhibin A and activin A in the first trimester of human pregnancy were not significantly different in the women with or without corpora lutea, suggesting a fetoplacental origin. Multiple donor egg pregnancies were found to have higher concentrations of inhibin A (P < 0.001) and activin A (P < 0.05) compared with singleton donor egg pregnancies, which also supports a placental source.

Activins↗
PubMed1995

Weight loss results in significant improvement in pregnancy and ovulation rates in anovulatory obese women.

Obesity can affect ovulation and the chances of pregnancy. In this prospective study, a weight loss programme was assessed to determine whether it could help infertile overweight anovulatory women to establish ovulation and assist in achieving pregnancy, ideally without further medical intervention. The subjects acted as their own historical controls. They underwent a weekly programme of behavioural change in relation to exercise and diet over 6 months; those who did not complete the 6 months were treated as the comparison group. Women in the study group lost an average of 6.3 kg, with 12 of the 13 subjects resuming ovulation and 11 becoming pregnant, five of these spontaneously. Fitness, diet and psychometric measurements all improved. Fasting insulin and testosterone concentrations dropped significantly, while sex hormone binding globulin concentrations rose. None of these changes occurred in the comparison group. Thus, weight loss with a resultant improvement in ovulation, pregnancy outcome, self-esteem and endocrine parameters is the first therapeutic option for women who are infertile and overweight.

Adult↗