Biomedical subjects

J A Land

Publications and source records attributed to J A Land.

At least 19 recordsLinked to original sources

PubMed2006

Economic evaluations of single- versus double-embryo transfer in IVF.

Multiple pregnancies lead to complications and induce high costs. The most successful way to decrease multiple pregnancies in IVF is to transfer only one embryo, which might reduce the efficacy of treatment. The objective of this review is to determine which embryo-transfer policy is most cost-effective: elective single-embryo transfer (eSET) or double-embryo transfer (DET). Several databases were searched for (cost* or econ*) and (single embryo* or double embryo* or one embryo* or two embryo* or elect* embryo or multip* embryo*). On the basis of five exclusion criteria, titles and abstracts were screened by two individual reviewers. The remaining papers were read for further selection, and data were extracted from the selected studies. A total of 496 titles were identified through the searches and resulted in the selection of one observational study and three randomized studies. Study characteristics, total costs and probability of live births were extracted. Besides this, cost-effectiveness and incremental cost-effectiveness were derived. It can be concluded that DET is the most expensive strategy. DET is also most effective if performed in one fresh cycle. eSET is only preferred from a cost-effectiveness point of view when performed in good prognosis patients and when frozen/thawed cycles are included. If frozen/thawed cycles are excluded, the choice between eSET and DET depends on how much society is willing to pay for one extra successful pregnancy.

Embryo Transfer↗

PubMed2006

Chlamydia trachomatis-associated tubal factor subfertility: Immunogenetic aspects and serological screening.

Chlamydia (C.) trachomatis female genital tract infections usually remain asymptomatic and untreated. Therefore, an adequate immune response, rather than antibiotic treatment, is essential to clear the pathogen. Most women will effectively clear C. trachomatis infections, but some will have persistent C. trachomatis infections, which may ascend to the upper genital tract and increase the risk of tubal factor subfertility. Pattern recognition receptors (PRRs) of the toll-like receptor (TLR) and nucleotide-binding oligomerization domain (NOD) families recognize C. trachomatis and initiate the immune response. Host immune factors are determinants of the course of C. trachomatis infections. Genetic variations in TLR and NOD genes may affect receptor function, leading to inadequate recognition of C. trachomatis, an inadequate immune response, and consequently an increased risk of persistence and late sequelae. For the risk assessment of tubal pathology in subfertile women, C. trachomatis immunoglobulin (Ig) G antibody testing (CAT) in serum is widely used. A positive CAT is indicative of a previous infection but not of a persistent infection. Measuring serological markers of persistence, of which C-reactive protein (CRP) seems promising, in CAT-positive women may identify a subgroup of subfertile women with persistent C. trachomatis infections and the highest risk of tubal pathology.

C-Reactive Protein↗

PubMed2006

Chlamydia antibody testing in subfertile women.

In the majority of women, Chlamydia trachomatis infections remain asymptomatic. These unrecognized and untreated infections may increase the risk for tubal factor subfertility at a later age. Since the association between C. trachomatis IgG antibodies in serum and tubal pathology was noticed, C. trachomatis IgG antibody testing has been used as a screening test for tubal factor subfertility. The diagnostic accuracy of C. trachomatis IgG antibody testing is limited, however. Since women who have persistent chlamydia infections are considered to be at the highest risk for developing late sequelae, the predictive value of markers of persistent infections have been studied in subfertile women. Patients who had C. trachomatis IgG antibodies (as markers of a previous infection), and an elevated C-reactive protein within the normal range (as a marker of a persisting infection) had the highest risk for having tubal pathology.

Antibodies, Bacterial↗

PubMed2006

Description of the ICTI consortium: an integrated approach to the study of Chlamydia trachomatis infection.

The use of an integrated approach to the study of Chlamydia trachomatis infection of the female genital tract, presented at the mini-symposium "Chlamydia trachomatis infections" and described in the thesis of Joseph M. Lyons, has resulted in the creation of the ICTI consortium. The ICTI consortium is based on strong interaction and collaboration between basic scientists, clinicians, epidemiologists, and health care policy makers. This translational approach will help to further the valuable insight into the immunopathogenesis of this sexually transmitted infection (STI) and the development of new intervention strategies, including the vaccines and screening programs necessary to effectively diagnose, treat and prevent C. trachomatis infection. A background of the need for this integrated approach is presented and the goals and participants of the consortium are described.

Animals↗

PubMed2005

Is controlled ovarian stimulation in intrauterine insemination an acceptable therapy in couples with unexplained non-conception in the perspective of multiple pregnancies?

BACKGROUND: Controlled ovarian stimulation (COS) with intrauterine insemination (IUI) is a common treatment in couples with unexplained non-conception. Induction of multifollicular growth is considered to improve pregnancy outcome, but it contains an increased risk of multiple pregnancies and ovarian hyperstimulation syndrome. In this study the impact of the number of follicles (>14 mm) on the ongoing pregnancy rate (PR) and multiple PR was evaluated in the first four treatment cycles. METHODS: A retrospective cohort study was performed in all couples with unexplained non-conception undergoing COS-IUI in the Academic Hospital of Maastricht. The main outcome measure was ongoing PR. Secondary outcomes were ongoing multiple PR, number of follicles of >or=14 mm, and order of treatment cycle. RESULTS: Three hundred couples were included. No significant difference was found in ongoing PR between women with one, two, three or four follicles respectively (P=0.54), but in women with two or more follicles 12/73 pregnancies were multiples. Ongoing PR was highest in the first treatment cycle and declined significantly with increasing cycle order (P=0.006), while multiple PR did not change. CONCLUSIONS: In COS-IUI for unexplained non-conception, induction of more than one follicle did not improve the ongoing PR, but increased the risk of multiple pregnancies. Multiple PR remained high in the first four cycles with multifollicular stimulation. Therefore, in order to reduce the number of multiple pregnancies, in all IUI cycles for unexplained non-conception monofollicular growth should be aimed at.

Cohort Studies↗

PubMed2005

Serological markers of persistent C. trachomatis infections in women with tubal factor subfertility.

BACKGROUND: Persistent C. trachomatis infections are assumed to increase the risk of tubal pathology. We studied whether serological markers, assumed to be associated with persistent C. trachomatis infections, could identify subfertile women at risk of tubal pathology. METHODS: Sera of 313 subfertile women, who all underwent a laparoscopy with tubal testing to assess the grade of tubal pathology, were tested for the presence of immunoglobulin (Ig) G and IgA antibodies to C. trachomatis, IgG antibodies to chlamydia heat shock protein 60 (cHSP60) and C-reactive protein (CRP). RESULTS: C. trachomatis IgA, cHSP60 IgG and CRP, all serological markers of persistent infections, were significantly more prevalent in women with tubal pathology as compared to those without tubal pathology. The predictive value of the currently used screening test for tubal pathology (IgG to C. trachomatis) could be significantly improved by adding the CRP test. CONCLUSIONS: In subfertile women with tubal pathology, serological markers of persistent C. trachomatis infections are significantly more common as compared to women without tubal pathology. C. trachomatis IgG-positive subfertile women with slightly elevated (< 10 mg/l) CRP levels are at highest risk of persistent C. trachomatis infections and tubal pathology.

Adult↗

PubMed2004

[Results from 10 years of preimplantation-genetic diagnostics in The Netherlands].

OBJECTIVE: To report the data from couples who were referred for preimplantation-genetic diagnostics (PGD) and treatment due to a significantly increased risk of offspring with a serious genetic disorder. DESIGN: Descriptive, prospective. METHOD: Data were collected from couples that underwent PGD in the period 1993/'03 at Maastricht University Hospital. Embryos produced by means of in-vitro fertilisation (IVF) were subjected to genetic tests several days after fertilisation. Subsequently 1 or 2 unaffected embryos were transferred to the uterus. Where there was an increased risk of a male with an X-linked genetic disorder, the gender was determined using fluorescence in-situ hybridisation (FISH). This method was also used to detect structural chromosomal abnormalities. The polymerase chain reaction (PCR) method was used for mutation detection and/or marker analysis of monogenetic disorders. RESULTS: A total of 691 couples were referred for PGD. The most frequent indications were X-linked disorders (30%), in particular Fragile-X syndrome, Duchenne/Becker muscular dystrophy and haemophilia A/B. This was followed by autosomal dominant disorders (26%), such as Huntington's disease and myotonic dystrophy, and then structural chromosomal abnormalities (24%). A total of 120 women underwent 260 PGD cycles. An embryo transfer was possible in 158 of the cycles and this resulted in 45 successful pregnancies. The pregnancy rate was 17% per cycle initiated and 28% per cycle with embryo transfer. Up until december 2003 29 singletons, 8 sets of twins and 1 set of triplets were born. There were no misdiagnoses and none of the babies had congenital abnormalities. CONCLUSION: PGD was a reliable and successful method, with pregnancy rates similar to those of IVF or intracytoplasmatic sperm injection. PGD should be stated as an alternative during the preconception counselling of couples with an increased genetic risk, especially for disorders where PGD can be routinely applied, such as Huntington's disease, myotonic dystrophy, cystic fibrosis, spinal muscular atrophy, Fragile-X syndrome and structural chromosomal abnormalities.

Adult↗

PubMed2004

Cost-effectiveness of Chlamydia antibody tests in subfertile women.

BACKGROUND: For the evaluation of tubal function, Chlamydia antibody testing (CAT) has been introduced as a screening test. We compared six CAT screening strategies (five CAT tests and one combination of tests), with respect to their cost-effectiveness, by using IVF pregnancy rate as outcome measure. METHODS: A decision analytic model was developed based on a source population of 1715 subfertile women. The model incorporates hysterosalpingography (HSG), laparoscopy and IVF. To calculate IVF pregnancy rates, costs, effects, cost-effectiveness and incremental costs per effect of the six different CAT screening strategies were determined. RESULTS: pELISA Medac turned out to be the most cost-effective CAT screening strategy (15 075 per IVF pregnancy), followed by MIF Anilabsystems (15 108). A combination of tests (pELISA Medac and MIF Anilabsystems; 15 127) did not improve the cost-effectiveness of the single strategies. Sensitivity analyses showed that the results are robust for changes in the baseline values of the model parameters. CONCLUSIONS: Only small differences were found between the screening strategies regarding the cost-effectiveness, although pELISA Medac was the most cost-effective strategy. Before introducing a particular CAT test into clinical practice, one should consider the effects and consequences of the entire screening strategy, instead of only the diagnostic accuracy of the test used.

Antibodies, Bacterial↗

PubMed2004

The role of chlamydia genus-specific and species-specific IgG antibody testing in predicting tubal disease in subfertile women.

BACKGROUND: We evaluated whether measuring chlamydia genus- and species-specific immunoglobulin (Ig) G antibodies might improve the predictive value of C. trachomatis antibody testing (CAT) in screening for distal tubal pathology (DTP). METHODS: Serum of 313 subfertile women was tested for the presence of species-specific antibodies to C. trachomatis, C. pneumoniae and C. psittaci and genus-specific antibodies to chlamydia lipopolysaccharide (LPS). Only patients who had undergone a laparoscopy with tubal testing, to assess the grade of DTP, were included in this study. RESULTS: The presence of C. trachomatis antibodies was the only independent predictor for DTP. The predictive value of CAT for DTP could not be improved by adding test results of C. pneumoniae or LPS antibody testing. The role of C. psittaci could not be evaluated, due to the absence of C. psittaci-positive patients in our cohort. CONCLUSIONS: In spite of the high interspecies homology, C. pneumoniae does not contribute to the development of DTP. Anti-LPS antibodies, which are considered to be markers for ongoing infections, do not identify C. trachomatis-positive subfertile women who are at highest risk of DTP. The high prevalence of anti-LPS antibodies in C. trachomatis-positive subfertile women may suggest that C. trachomatis remains more active in the upper genital tract than currently is presumed.

Adult↗

PubMed2003

Risks and complications in assisted reproduction techniques: Report of an ESHRE consensus meeting.

Assisted reproduction technique (ART) is an efficacious treatment in subfertile couples. So far little attention has been paid to the safety of ART, i.e. to its adverse events and complications. The consensus meeting on Risks and Complications in ART held in Maastricht in May 2002 focused on four topics: multiple pregnancies, long-term effects of ART on women, effects of ART on offspring, and morbidity/mortality registries.

Breast Neoplasms↗

PubMed2003

Performance of five serological chlamydia antibody tests in subfertile women.

BACKGROUND: Micro-immunofluorescence (MIF) is widely used for chlamydia antibody testing (CAT). Recently a species-specific MIF and three enzyme-linked immunosorbent assay (ELISA) tests have been introduced. We compared five commercially available CAT tests, using laparoscopy as a reference, and evaluated whether combinations of tests could improve the predictive value of CAT. METHODS: In a consecutive cohort of 315 subfertile women, results of the five CAT tests were correlated to findings at laparoscopy. Likelihood and odds ratios (OR) were calculated for single tests and for combinations of tests. RESULTS: Of the tests evaluated, MIF Labsystems had the best diagnostic performance (OR 15.7), while pELISA Medac (OR 8.2) was the best of the three ELISA tests. Stepwise logistic regression analysis showed that performance of MIF Labsystems could not be improved by adding a second test. Significant cross-reactivity with C. pneumoniae antibodies was found in all tests evaluated, except in pELISA Medac. CONCLUSIONS: In screening for tubal factor subfertility, MIF Labsystems was superior to the ELISA tests evaluated, and combining two CAT tests did not improve its predictive value. Economic analysis will show whether serial testing by pELISA Medac, and retesting positive samples by MIF Labsystems, is most cost-effective. In CAT, cross-reactivity with C. pneumoniae antibodies is still a major concern.

Antibodies, Bacterial↗

PubMed2002

[Results of in vitro fertilization in the Netherlands, 1996-2000].

OBJECTIVE: To describe the annual results in all 13 Dutch in vitro fertilisation (IVF) centres in the period 1996-2000, and to look for possible differences between individual centres and years. DESIGN: Retrospective data collection, description and analysis. METHOD: The results collected on the website of the Dutch Society of Obstetrics and Gynaecology (Dutch acronym: NVOG; www.nvog.nl) in the period 1996-2000 were integrated and described, with special attention to possible differences between centres and years. RESULTS: In 1996-2000 (5 years), 63,414 IVF or ICSI treatment cycles were started in the Netherlands, and 5,884 transfers of cryopreserved embryos were performed. The number of treatment cycles increased over the years, particularly the number of ICSI cycles. The total number of ongoing pregnancies was 12,991 (20.5% per started cycle; 22.5% for ICSI and 18.3% for IVF). Particularly during the first 3 years, there was an increase in these percentages (IVF: from 16.4% (1996) to 19.2% (1998); ICSI: from 18.3% (1996) to 23.9% (1998)). There were differences between the centres in both the percentage of ongoing pregnancies per started IVF/ICSI cycle (range 13.7-25.1%) and the percentage ICSI (14-61%) and cryo-transfers per total number of treatment cycles (0-26%). It was estimated that, during this 5-year period, 1 out of every 61 Dutch neonates resulted from IVF or ICSI. CONCLUSION: The pregnancy-rates after IVF and ICSI increased during the study period, and were comparable with the rates in other European countries. Some important data are still missing from the inventory, for example regarding the number of embryos per transfer, multiple pregnancies, live births, congenital malformations and complications.

Embryo Transfer↗

PubMed2001

[Macroprolactinemia, a benign form of hyperprolactinemia].

In a 34-year-old woman with primary subfertility, a strongly increased serum concentration of prolactin was found in combination with normal levels of oestradiol, which is an indication for the presence of prolactin forms without clinical effect. She appeared to have macroprolactinaemia, i.e. the presence of circulating large forms of prolactin (up to > 100 kDa), which may be detected by the immunoassays currently used. They give no clinical signs or symptoms. Diagnosing macroprolactinaemia means that further diagnostic tests for hypopituitarism abnormalities using MRI need not be carried out and unjustified treatment of otherwise healthy persons may be prevented.

Adult↗

PubMed2001

Chlamydia pneumoniae and screening for tubal factor subfertility.

Chlamydia antibody testing (CAT) by micro-immunofluorescence (MIF) tests has been introduced into the fertility work-up as a screening test for tubal factor subfertility. In this study the role of C. pneumoniae antibodies, as a cause for false positive CAT results due to cross-reactivity with C. trachomatis antibodies in the MIF test, has been evaluated. In 240 subfertile women serological data were compared to laparoscopy findings. The prevalence of C. pneumoniae antibodies using enzyme-linked immunosorbent assay (ELISA) was 75% and did not differ between patients with and without tubal pathology. C. pneumoniae antibodies were found in 87% of women with a positive MIF test (> or =32), and in 66% with a negative MIF test (P < 0.0005). Using ELISA instead of MIF for the detection of C. trachomatis antibodies, C. pneumoniae antibodies were found in 87% of C. trachomatis positive women, and in 69% of C. trachomatis negative women (P < 0.0005). Patients without tubal factor subfertility but a positive MIF test showed C. pneumoniae antibodies more frequently than patients without tubal factor subfertility and a negative MIF test. Therefore it was suggested that C. pneumoniae antibodies may be the cause of false positive CAT results. Remarkably, tubal pathology was more common in patients who had antibodies to both C. trachomatis and C. pneumoniae.

Adult↗

PubMed1998

[Genetic diagnosis of IVF embryos: preliminary results from 'preimplantation genetic diagnoses' in the Netherlands].

Preimplantation genetic diagnosis (PGD) is a very early form of genetic testing. It involves testing one or two cells taken from a recent embryo of eight cells produced by in vitro fertilization, and selective transfer of genetically normal embryos. So far in the Academic Hospital Maastricht, the Netherlands, 20 couples have undergone PGD, resulting in 6 ongoing pregnancies (one twin pregnancy). In three women the indications for PGD were: cystic fibrosis, sex-linked Pelizaeus-Merzbacher disease and chromosomal translocation, respectively. In the Netherlands PGD is only allowed if there is a high risk of a serious genetic disease. PGD can be carried out in Maastricht for: cystic fibrosis, sex-linked diseases, chromosomal abnormalities, fragile X syndrome, spinal muscular atrophy and myotonic dystrophy. The advantage of PGD is that it excludes the necessity of a therapeutic abortion. Disadvantages ages are the requirement of in vitro fertilization, which has only a 15-20% pregnancy rate, and the experimental nature of the PGD procedure. To date, about 200 children have been born worldwide following PGD.

Adult↗

PubMed1998

Elevated levels of basal estradiol-17beta predict poor response in patients with normal basal levels of follicle-stimulating hormone undergoing in vitro fertilization.

OBJECTIVE: To evaluate whether the predictive ability of a normal FSH level on cycle day 3 can be enhanced by levels of estradiol-17beta (E2) on cycle day 3. DESIGN: Prospective cohort study. SETTING: University hospital-based, tertiary care infertility center. PATIENT(S): Two hundred thirty-one consecutively seen patients who attended the center for their first IVF attempt. INTERVENTION(S): Blood samples were collected on day 3 of the cycle preceding IVF; IVF was performed in all patients. MAIN OUTCOME MEASURE(S): Patient's age, number of ampules of hMG, cancellation rate, number of oocytes, fertilization rate, and clinical pregnancy rate. RESULT(S): In patients with elevated FSH levels on cycle day 3, a low oocyte yield was achieved (7 versus 11) and a high number of ampules of hMG was necessary (56 versus 33). Their cancellation rate was high (67% versus 16%). In patients with normal basal FSH levels, high E2 levels predicted a high cancellation rate (56%, versus 13% in patients with low E2 levels) and a low oocyte yield (9, versus 11 in patients with low E2 levels). Patients with both normal FSH levels and low E2 levels on cycle day 3 fared best. CONCLUSION(S): The basal E2 level on cycle day 3 is a useful prognosticator of response to stimulation in IVF patients with normal basal FSH levels.

Adult↗

PubMed1998

"The Flemish Giant", reflections on the defense against endometriosis, inspired by Professor Emeritus Ivo A. Brosens.

Reproductive research benefits from combining animal and clinical studies. In Leuven, rabbits have constituted an animal model for many reproductive disorders, especially for those that involved surgical treatment. Much of what has been learned from animal experiments has been applied to human clinical reproductive research soon after. In this manuscript we wish to address the problem of the constant intra-abdominal battle between the menstrual aggressor and the peritoneal defense. From all published evidence we may conclude that endometriosis appears to be a dynamic disease, especially in the early phase, with subtle, atypical lesions emerging and vanishing again. In the end however the peritoneal defense system will prevail and the disease will be contained in the majority of patients. When doing repeat laparoscopies in young patients one should be prepared to encounter more advanced histological types of lesions, which not necessarily do have to indicate more advanced stages of the disease: the classical, blue and black powderburn spots and blueberry lesions reflect the extinguishing phase of the dynamic endometriotic process, and herald its inactivated histological end-stage. The dynamic phase of the disease may involve a varying interval of each patient's life, and medical suppression of the activity of the implants during this interval may lead one to conclude erroneously that treatment has been effective. If subsequently (after the end of medical suppression of the activity of the lesions) ovarian activity resumes and the lesions are stimulated again by ovarian steroids, their productive activity returns. Recurrence of disease may be diagnosed if at that stage a laparoscopy would be performed, whereas in reality only reactivation of temporarily obscured lesions did occur. The suppressed, dormant (but never absent) lesions produce mucus again, desquamation occurs, and reaction by the surrounding tissue. The inflammatory response, the local hyperemia and the neogenesis of vessels accentuate the presence of previously invisible endometriosis lesions and make them visible again. Endometriosis resumes its temporarily halted natural course of development, tissue remodeling occurs again, the battle between the aggressor and the defense resumes and waxing and waning of the several types of lesions, red, white and black, can be found again.

Animals↗

PubMed1998

How to use Chlamydia antibody testing in subfertility patients.

Screening for tubal factor subfertility by means of Chlamydia antibody testing (CAT) was introduced into the initial work-up of subfertile couples several years ago. The results reported, however, are heterogeneous, and no uniformity exists in cut-off levels of titres, or in definitions of tubal factor subfertility. We performed a prospective cohort study to evaluate the implications of varying the definitions of tubal pathology and of modifying the cut-off levels on the clinical impact of CAT in predicting tubal factor subfertility. In 227 consecutive patients who attended our fertility clinic, the Chlamydia IgG antibody titre was determined and related to tuboperitoneal abnormalities at laparoscopy as a reference standard. According to received operating characteristic (ROC) curve analysis, a titre of 16 is the optimum cut-off level. Increasing the cut-off level improves specificity and positive likelihood ratio (LR+), at the expense of sensitivity and negative LR (LR-). Changing the definition of tubal factor subfertility from unspecified tuboperitoneal abnormalities into extensive adhesions and/or bilateral distal tubal occlusion improves LR+, LR- and kappa significantly. We conclude that CAT is more accurate in predicting severe distal tubal pathology than unspecified tuboperitoneal abnormalities. Although from a statistical point of view a titre of 16 is the optimum cut-off level, from a clinical point of view 32 or 64 may be preferable, depending on the aim of screening and the inception cohort.

Antibodies, Bacterial↗