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A Verhoeff

Publications and source records attributed to A Verhoeff.

At least 19 recordsLinked to original sources
PubMed2001

Indicators without a cause. Reflections on the development and use of indicators in health care from a public health perspective.

Indicators have a long history in public health. Since the end of the 18th century information on the health of communities has been gathered on a health system level and public health indicators have become more sophisticated over the vears. However, in many modern health care systems there is a separation between public health and health services. This paper discusses the need for integration and promotes a stronger public health orientation of health services. This has consequences for the nature of indicators on the health services level. The methodological problems of turning epidemiological data into management information for health services are discussed. The key message is that the health of the community should be the ultimate cause of all indicators.

Delivery of Health Care↗
PubMed2000

Daily mortality and air pollution in The Netherlands.

We studied the association of daily mortality with short-term variations in the ambient concentrations of major gaseous pollutants and PM in the Netherlands. The magnitude of the association in the four major urban areas was compared with that in the remainder of the country. Daily cause-specific mortality counts, air quality, temperature, relative humidity, and influenza data were obtained from 1986 to 1994. The relationship between daily mortality and air pollution was modeled using Poisson regression analysis. We adjusted for potential confounding due to long-term and seasonal trends, influenza epidemics, ambient temperature and relative humidity, day of the week, and holidays, using generalized additive models. Influenza episodes were associated with increased mortality up to 3 weeks later. Daily mortality was significantly associated with the concentration of all air pollutants. An increase in the PM10 concentration by 100 micrograms/m3 was associated with a relative risk (RR) of 1.02 for total mortality. The largest RRs were found for pneumonia deaths. Ozone had the most consistent, independent association with mortality. Particulate air pollution (e.g., PM10, black smoke [BS]) was not more consistently associated with mortality than were the gaseous pollutants SO2 and NO2. Aerosol SO4(-2), NO3-, and BS were more consistently associated with total mortality than was PM10. The RRs for all pollutants were substantially larger in the summer months than in the winter months. The RR of total mortality for PM10 was 1.10 for the summer and 1.03 for the winter. There was no consistent difference between RRs in the four major urban areas and the more rural areas.

Adolescent↗
PubMed2000

Decrease of free thyroxine levels after controlled ovarian hyperstimulation.

Controlled ovarian hyperstimulation could lead to opposing effects on thyroid function. Therefore, in a prospective study of 65 women undergoing controlled ovarian hyperstimulation, thyroid hormones, T4-binding globulin, TPO antibodies, gonadotropins, estradiol, and PRL were measured before and after controlled ovarian hyperstimulation. After ovarian stimulation (mean +/- SE of mean): free T4 decreased, 14.4 +/- 0.2 vs. 12.9 +/- 0.2 pmol/L (P < 0.0001); thyroid-stimulating hormone increased, 2.3 +/- 0.3 vs. 3.0 +/- 0.4 mU/L (P < 0.0001); T4-binding globulin increased, 25.2 +/- 0.7 vs. 33.9 +/- 0.9 mg/L (P < 0.0001); total T4 increased, 98.1 +/- 2.3 vs. 114.6 +/- 2.5 nmol/L (P < 0.0001); total T3 increased, 2.0 +/- 0.04 vs. 2.3 +/- 0.07 nmol/L (P < 0.0001); TPO antibodies decreased, 370 +/- 233 U/mL vs. 355 +/- 224 U/mL (P < 0.0001); LH decreased, 8.1 +/- 1.1 vs. 0.4 +/-0.1 U/L (P < 0.0001); FSH did not change, 6.5 +/- 0.6 vs. 7.9 +/- 0.9 U/L (P = 0.08); human CG increased, <2 +/- 0.0 vs. 195 +/- 16 U/L (P < 0.0001); estradiol increased, 359.3 +/- 25.9 pmol/L vs. 3491.8 +/-298.3 pmol/L (P < 0.0001); and PRL increased, 0.23 +/- 0.02 vs. 0.95 +/- 0.06 U/L (P < 0.0001). Because low maternal free T4 and elevated maternal thyroid-stimulating hormone levels during early gestation have been reported to be associated with impaired psychomotor development in the offspring, our findings indicate the need for additional studies in the children of women who where exposed to high levels of estrogens around the time of conception.

Adult↗
PubMed1999

Thyroid autoimmunity and abortion: a prospective study in women undergoing in vitro fertilization.

OBJECTIVE: To determine whether an association exists between the presence of thyroid peroxidase (TPO) antibodies before pregnancy and miscarriage in women without a history of habitual abortion. DESIGN: Prospective study and nested case-control study. SETTING: Inner-city teaching hospital. PATIENT(S): Four hundred eighty-nine women in an IVF program. INTERVENTION(S): In the prospective study, we measured levels of TPO antibodies and TSH. In the nested case-control study, we also measured levels of anticardiolipin antibodies. MAIN OUTCOME MEASURE: Miscarriage. RESULT(S): One hundred seventy-three women were observed, of whom 31% (54/173) became pregnant. Pregnancy occurred in 48% (12/25) of the antibody-positive women and in 28% (42/148) of the antibody-negative women. Among those who became pregnant, miscarriage occurred in 33% (4/12) of TPO antibody-positive women and in 19% (8/42) of TPO antibody-negative women. The TSH level was abnormal (<0.2 microIU/mL) in only one of the TPO antibody-positive women who miscarried. The presence of anticardiolipin antibodies was not associated with miscarriage. CONCLUSION(S): No association was found between the presence of TPO antibodies before pregnancy and miscarriage in women without a history of habitual abortion. The presence of TPO antibodies did not adversely affect a woman's chances of becoming pregnant.

Abortion, Spontaneous↗
PubMed1999

Fungal extracellular polysaccharides in house dust as a marker for exposure to fungi: relations with culturable fungi, reported home dampness, and respiratory symptoms.

BACKGROUND: Epidemiologic studies have demonstrated an association between indoor fungal growth and respiratory symptoms. However, in only a few studies was fungal exposure actually measured. OBJECTIVE: The purpose of this study was to evaluate the measurement by enzyme immunoassay of extracellular polysaccharides of Aspergillus and Penicillium species (EPS-Asp/Pen ) in house dust as a marker for fungal exposure and to study the relations between EPS-Asp/Pen levels and home dampness and respiratory symptoms in children. METHODS: Extracts of house dust samples from bedroom and living room floors and mattresses from homes of 31 children with chronic respiratory symptoms and 29 children with no chronic respiratory symptoms were analyzed for EPS-Asp/Pen. RESULTS: EPS-Asp/Pen were readily detectable (40 to 46,513 nanogram equivalent/g dust) in 161 house dust extracts, with highest concentrations in living room floor dust. EPS-Asp/Pen levels were 2 to 3 times higher on carpeted floors than on smooth floors. EPS-Asp/Pen were significantly correlated with total culturable fungi (r = 0.3 to 0.5) and with house dust mite allergens (r = 0.3 to 0.5). EPS-Asp/Pen levels in living room floor dust were positively associated with occupant-reported home dampness. This was not observed for EPS-Asp/Pen in bedroom floor and mattress dust. EPS-Asp/Pen levels in living room floor dust were positively associated with respiratory symptoms. EPS-Asp/Pen in bedroom floor and mattress dust showed a reversed association with respiratory symptoms, possibly because of allergen-avoidance measures taken in the bedroom. CONCLUSION: The enzyme immunoassay for fungal EPS-Asp/Pen may be a useful method for exposure assessment of indoor fungi.

Antigens, Fungal↗
PubMed1998

Treatment policy after poor fertilization in the first IVF cycle.

PURPOSE: The chance of recurrence of poor fertilization in a second in vitro fertilization (IVF) cycle was assessed. METHODS: Total fertilization failure was defined, and the relationship between the fertilization rate and the number of motile sperm cells per milliliter of semen was assessed. Patients with a total fertilization failure or poor fertilization (20% or less of the oocytes fertilized) were divided into three subgroups with different chances of fertilization and were followed in a subsequent IVF cycle. RESULTS: The recurrence rate of total fertilization failure was high in all three groups (45-70%), and poor fertilization frequently occurred in the second cycle (50-75%). CONCLUSIONS: Poor fertilization frequently recurs in the second IVF cycle. The use of intracytoplasmic sperm injection could be considered after fertilization of 20% or less of oocytes in the first cycle, irrespective of the number of motile sperm cells per milliliter of semen.

Female↗
PubMed1998

Cumulative pregnancy rates and selective drop-out of patients in in-vitro fertilization treatment.

The validity of the cumulative pregnancy rate (CPR) calculated by life-table approach, obtained in a transport in-vitro fertilization (IVF) programme, was tested by the determination of possible influence of selective drop-out of patients with a poor treatment prognosis. A cohort of 1211 patients who had a first IVF cycle was followed, and the CPR after three IVF cycles was assessed. First cycles of patients who discontinued treatment after failed IVF, and of those who did not achieve a pregnancy but proceeded to a subsequent cycle, were compared for fertilization rate and for occurrence of prognosticators of poor treatment outcome: oocyte yield < or =2, and replacement of <2 embryos. The CPR after three cycles was 54.9%. No differences were found in the first and second cycles of patients who continued treatment and those who dropped out. Selective drop-out of patients with a poor treatment prognosis was not found. Therefore, although calculations of CPR using life-table analysis generally overestimate the real probability of pregnancy after successive IVF cycles, the calculated CPR after three IVF cycles gives a reliable indication of the chance of occurrence of a pregnancy for the population studied.

Adult↗
PubMed1997

A triplet pregnancy after in vitro fertilization is a procedure-related complication that should be prevented by replacement of two embryos only.

OBJECTIVE: To investigate whether the incidence and obstetric outcome of triplet pregnancies after IVF treatment justify strict limitation of the number of embryos to be replaced to two. DESIGN: Retrospective analysis. SETTING: A transport IVF program. PATIENT(S): All patients who had more than one embryo replaced. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Obstetric outcome, pregnancy. RESULT(S): High-order pregnancies occurred in 24 cases (23 triplets and 1 quadruplet). Three patients opted for selective embryo reduction (12.5%). Three triplet pregnancies spontaneously reduced to twins. Comparison of 18 triplets, reaching at least 20 weeks' gestation, with 54 twin pregnancies shows a higher perinatal mortality in the triplet group, causing 6 out of 18 patients to be confronted with at least one perinatal death. Triplets were born at a lower gestational age, had a lower birth weight, and a higher hospital admission rate of longer duration. Replacement of two, three, or four embryos did not lead to differences in pregnancy rates in the population studied. When a pregnancy occurred after replacement of three embryos, the risk of having a triplet pregnancy was 7.5%. CONCLUSION(S): The obstetric outcome of triplet pregnancies in our population indicates that triplet pregnancies after IVF treatment have to be prevented. Selective embryo reduction is acceptable for few patients only and can therefore not be seen as a solution. Replacement of three embryos results in triplet pregnancy in an unacceptably high percentage. Replacement of two embryos only gives acceptable IVF results and is the method chosen in the IVF program in Rotterdam to prevent triplet pregnancies.

Birth Weight↗
PubMed1997

Determination of the parent of origin in nine cases of prenatally detected chromosome aberrations found after intracytoplasmic sperm injection.

Prenatal cytogenetic analysis of 71 fetuses conceived by intracytoplasmic sperm injection (ICSI) resulted in the detection of nine (12.7%) chromosome aberrations including two cases of 47,XXY, four cases involving a 45,X cell line and three autosomal trisomies. Molecular analysis of the parental origin of the deleted or supernumerary chromosome was performed by using polymorphic microsatellite markers. Six cases involving a sex chromosome abnormality were found to be of paternal origin while the two trisomic cases that could be analysed were of maternal origin. Two cases involved the same infertile couple who had two consecutive ICSI pregnancies terminated because of a chromosome abnormality. The replaced embryos in both cases originated from a single batch of ICSI fertilized oocytes of which part was used to initiate the first pregnancy and part was cryopreserved and used to initiate the second pregnancy.

Chromosome Aberrations↗
PubMed1997

A randomized study on the effects of intramuscular injections with urinary gonadotrophins (Humegon or Pergonal) on pain, local redness and fever in infertile women opting for in-vitro fertilization.

The objective of this open, multicentre, randomized controlled study in women opting for in-vitro fertilization was to compare the occurrence of pain and redness at the injection site and of post-injection fever after i.m. injection with Humegon (n = 89) or Pergonal (n = 92). Assessments were scoring of pain and redness at the injection site and of post-injection fever during the next 24 h using self-administered questionnaires. Injection site pain was reported in 48.9% of injections with Humegon and in 44.9% with Pergonal (P = 0.45). A trend was seen towards more redness after Pergonal injection (24.0 versus 15.5%; P = 0.08). Post-injection fever was reported in 1.4% with Humegon and in 1.1% with Pergonal (P = 0.80). It was concluded that there are no statistically significant differences between Humegon and Pergonal after i.m. injection with respect to the prevalence of pain and redness at the injection site and of post-injection fever.

Adult↗
PubMed1997

Transport-in-vitro fertilization/intracellular sperm injection: a prospective randomized study.

We performed a prospective randomized clinical trial to investigate whether long distance oocyte transport prior to an intracytoplasmic sperm injection (ICSI) procedure influences fertilization rates, embryo quality and/or embryo implantation rates. After informed consent, 100 infertile couples booked for ICSI treatment were randomized into two groups. In group 1 (n = 50), patients were stimulated and monitored in Rotterdam (The Netherlands), and oocyte retrieval, ICSI procedure and embryo transfer took place in Gent (Belgium). In group 2 (n = 50), patients were stimulated, monitored and punctured in Rotterdam and the oocytes were transported in their follicular fluid in an isothermic transport box to Gent, where the ICSI procedure and the embryo transfer took place. In both groups the stimulation and monitoring regimen, puncture technique, laboratory conditions and transfer policy were identical. In both groups, the number of fertilized oocytes (7.13 +/- 0.65 versus 5.53 +/- 0.60, P = 0.08), the number of transferred embryos (2.36 +/- 0.09 versus 2.40 +/- 0.11, P = 0.87) and the embryo implantation rate [20/113 (17.7%) versus 19/103 (18.4%), P = 0.89] was similar. In group 1, the number of retrieved oocytes was higher (10.83 +/- 0.95 versus 8.44 +/- 0.93, P = 0.05). The total score of the embryos obtained (18.90 +/- 1.73 versus 12.64 +/- 1.26, P = 0.01), the number of good quality embryos (4.63 +/- 0.49 versus 2.98 +/- 0.38, P = 0.02), the mean score of the transferred embryos (3.32 +/- 0.11 versus 2.94 +/- 0.13, P = 0.05) and the number of embryos available for cryopreservation (2.70 +/- 0.45 versus 1.48 +/- 0.38, P = 0.03) were significantly higher in group 1. Therefore, long distance transport of oocytes prior to ICSI does not affect oocyte fertilization and embryo implantation rates, although a negative effect on embryo quality cannot be excluded.

Adult↗
PubMed1996

Transport intracytoplasmic sperm injection (ICSI): a cost-effective alternative.

PURPOSE: Transport in vitro fertilization (IVF) programs are operational in a lot of countries and especially popular in The Netherlands, where IVF activities are strictly regulated. Since the introduction of intracytoplasmic sperm injection (ICSI) in the IVF laboratory, many laboratories are now setting up this new technique, which necessitates major investments in terms of infrastructure and specialized personnel. METHODS: We present a cost effective alternative, consisting of patient selection, preparation, and oocyte retrieval at one center and transport of oocytes to a second center, where the ICSI procedure and embryo transfer are performed. Since early 1994 several Dutch centers have a transport ICSI program running with the Gent University Infertility Center, and we wish to present the results of our cooperation with two major centers, comparing them to our local results, for the first 10 months of 1994. Patient selection was similar at all three centers: only couples with previously failed in vitro fertilization or having been refused for routine IVF were enrolled in the program. Stimulation schemes and follow-up of the stimulation were different at all three centers. Transport of oocytes was carried out in a transport box or by attaching the closed tubes containing the follicular aspirates to the chest of the husband. Transport times varied between 1.5 and 3 hr, depending on traffic conditions. RESULTS: Up to November 1, 1994, a total of 77 transport ICSI cycles and 294 own ICSI cycles were carried out. Although locally significantly more oocytes were retrieved and thus available for ICSI than in transport cycles, fertilization and pregnancy rates were not different between the two groups. CONCLUSIONS: These results suggest that long-distance transport of human oocytes seems not to be harmful to their capacity to be successfully injected and to further embryonic development and their implantation potential. Transport ICSI seems to be a valuable and cost-effective approach to treat high numbers of patients at a restricted number of highly specialized IVF laboratories, especially in countries where ICSI is not commonly available.

Academic Medical Centers↗
PubMed1996

The ovarian response as a predictor for successful in vitro fertilization treatment after the age of 40 years.

OBJECTIVE: To determine whether age or response to controlled ovarian hyperstimulation (COH) is a better predictor of IVF outcome in women > or = 40 years. DESIGN: Retrospective analysis. SETTING: A transport IVF program. PATIENT(S): For patients undergoing IVF treatment the correlation between treatment outcome and age and response to COH was analyzed using the data of 2,588 consecutive cycles. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Pregnancy. RESULT(S): The incidence of poor ovarian response rises significantly with increasing age. Analysis of all cycles showed a significant decrease in clinical and ongoing pregnancy rate for women > or = 40 years. Analysis of cycles with a good ovarian response showed no statistically significant differences for these parameters between women > or = 40 years and those younger. A logistic regression analysis on pregnancy showed that ovarian response contributes more to the prediction of pregnancy than age. CONCLUSION(S): Patients aged > or = 40 years with a good response to COH have a good prognosis for IVF treatment. The age limit for acceptance of patients should not be set at 40 years. Instead, the response to COH can be used to predict candidates likely to have a successful IVF outcome.

Adult↗
PubMed1995

Minimal monitoring of ovarian hyperstimulation: a useful simplification of the clinical phase of in vitro fertilization treatment.

OBJECTIVE: To investigate the feasibility of IVF treatment with minimal monitoring during ovarian hyperstimulation. DESIGN: Retrospective analysis and prospective study with real-time control group. SETTING: Transport IVF program with transport clinic and satellite clinics. PATIENTS: One hundred consecutive IVF cycles monitored at a transport clinic and 100 concurrent consecutive cycles monitored at satellite clinics, using the same stimulation-monitoring protocol and resulting in oocyte aspiration, are compared retrospectively for the number of ultrasound (US) measurements carried out during monitoring and for results of IVF treatment. No patient selection took place. After introduction of a minimal monitoring protocol at a transport clinic, a prospective study was started comparing 100 minimal monitoring cycles at a transport clinic with 100 concurrent conventional monitoring cycles at satellite clinics, all resulting in oocyte aspiration. Patients entered the retrospective or prospective study only once. In all cases the same laboratory facility was used. Monitoring of ovarian hyperstimulation was done with US measurements only. Cycles were canceled for impending ovarian hyperstimulation syndrome (OHSS) when > 35 follicles were seen to develop during hyperstimulation. RESULTS: Retrospective analysis shows no difference for the average number of US measurements at transport and satellite clinics (2.8 +/- 0.9 and 3.0 +/- 1.0; mean +/- SD). No differences were found in the number of ongoing pregnancies obtained in the two groups: 22 and 18, respectively. One case of severe OHSS occurred in the satellite clinic group. Introduction of minimal monitoring at the transport clinic gives a significant reduction of the average number of US measurements at the transport clinic compared with satellite clinics, where conventional monitoring continued to be used (1.5 +/- 0.8 versus 2.8 +/- 0.9). Ongoing pregnancies at transport and satellite clinics numbered 33 and 26, respectively. In both groups one patient developed severe OHSS. Sixty-two percent of cycles at the transport clinic were monitored with one US measurement only. No cancellations for impending OHSS occurred during the study period. CONCLUSION: A large group of patients need only one US measurement during monitoring of ovarian hyperstimulation. Minimal monitoring gives a useful further simplification of the clinical phase of IVF treatment, without adverse effects on treatment outcome and incidence of OHSS.

Ambulatory Care Facilities↗
PubMed1995

Results of decentralized in-vitro fertilization treatment with transport and satellite clinics.

The results of in-vitro fertilization (IVF) treatments carried out in a university IVF centre are compared with those obtained following 15-40 min transportation of oocytes from a transport IVF clinic to the central IVF laboratory of the university centre. Moreover, treatment results following monitoring of ovarian stimulation in satellite clinics, combined with ovum retrieval at the transport clinic and transport of oocytes to the central IVF laboratory, are described. In a total of 5540 IVF treatment cycles, 24-26% of viable pregnancies per embryo transfer were found in the three groups. Comparison of results, obtained with the three different treatment modalities, showed no negative influences of transporting oocytes from transport clinic to IVF laboratory and of monitoring ovarian stimulation in satellite clinics. It is concluded that decentralization of the clinical phase of IVF treatment is possible. This leads to a more optimal use of existing laboratory facilities in large urban areas. It is stressed that good communication between satellite clinic, transport clinic and IVF laboratory is necessary for a decentralized IVF programme. To obtain good quality assurance, both the satellite clinic and the transport clinic must adhere to the same protocol.

Adult↗