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Featured researches published by Arnold Simons.


Human Reproduction | 2011

Risk of borderline and invasive ovarian tumours after ovarian stimulation for in vitro fertilization in a large Dutch cohort

F.E. van Leeuwen; Helen Klip; T.M. Mooij; A.M.G. Van de Swaluw; Cornelis B. Lambalk; M. Kortman; Joop S.E. Laven; C.A.M. Jansen; Frans M. Helmerhorst; B.J. Cohlen; Wim N.P. Willemsen; J.M.J. Smeenk; Arnold Simons; F. van der Veen; Johannes L.H. Evers; P.A. van Dop; Nick S. Macklon; Curt W. Burger

BACKGROUND Long-term effects of ovarian stimulation for IVF on the risk of ovarian malignancies are unknown. METHODS We identified a nationwide historic cohort of 19 146 women who received IVF treatment in the Netherlands between 1983 and 1995, and a comparison group of 6006 subfertile women not treated with IVF. In 1997–1999, data on reproductive risk factors were obtained from 65% of women and data on subfertility (treatment) were obtained from the medical records. The incidence of ovarian malignancies (including borderline ovarian tumours) through 2007 was assessed through linkage with disease registries. The risk of ovarian malignancies in the IVF group was compared with risks in the general population and the subfertile comparison group. RESULTS After a median follow-up of 14.7 years, the risk of borderline ovarian tumours was increased in the IVF group compared with the general population [standardized incidence ratio (SIR) = 1.76; 95% confidence interval (CI) = 1.16–2.56]. The overall SIR for invasive ovarian cancer was not significantly elevated, but increased with longer follow-up after first IVF (P = 0.02); the SIR was 3.54 (95% CI = 1.62–6.72) after 15 years. The risks of borderline ovarian tumours and of all ovarian malignancies combined in the IVF group were significantly increased compared with risks in the subfertile comparison group (hazard ratios = 4.23; 95% CI = 1.25–14.33 and 2.14; 95% CI = 1.07–4.25, respectively, adjusted for age, parity and subfertility cause). CONCLUSIONS Ovarian stimulation for IVF may increase the risk of ovarian malignancies, especially borderline ovarian tumours. More large cohort studies are needed to confirm these findings and to examine the effect of IVF treatment characteristics.


Prenatal Diagnosis | 1996

Maternal serum screening for fetal Down syndrome in IVF pregnancies

L. S. M. Ribbert; L. H. Kornman; B. T. H. M. De Wolf; Arnold Simons; C. A. M. Jansen; J. R. Beekhuis; A. Mantingh

To assess the influence of in vitro fertilization (IVF) on maternal serum human chorionic gonadotrophin (hCG) and alpha‐fetoprotein (AFP), the maternal serum hCG and AFP values were studied in 67 IVF pregnancies and compared with the results of a control group of 4732 spontaneously conceiving patients. Maternal serum hCG was significantly higher and AFP significantly lower in the IVF group. Possible explanations and implications for prenatal diagnosis in IVF pregnancies are discussed.


Journal of Clinical Oncology | 2007

Gonadal Function in Males After Chemotherapy for Early-Stage Hodgkin's Lymphoma Treated in Four Subsequent Trials by the European Organisation for Research and Treatment of Cancer: EORTC Lymphoma Group and the Groupe d'Étude des Lymphomes de l'Adulte

Marleen A.E. van der Kaaij; Natacha Heutte; Nolwenn Le Stang; John Raemaekers; Arnold Simons; Patrice Carde; Evert M. Noordijk; Christophe Fermé; José Thomas; Houchingue Eghbali; Hanneke C. Kluin-Nelemans; Michel Henry-Amar

PURPOSE To analyze fertility in male patients treated with various combinations of radiotherapy and chemotherapy, with or without alkylating agents, or with radiotherapy alone for Hodgkins lymphoma. PATIENTS AND METHODS Follicle-stimulating hormone (FSH) levels were measured in patients with early-stage upper-diaphragmatic disease enrolled in four European Organisation for Research and Treatment of Cancer (EORTC) trials (H6-H9). Median follow-up after therapy was 32 months. Patients with FSH measurement at least 12 months after end of treatment (n = 355) were selected to assess post-treatment fertility. Patients with FSH measurement 0 to 9 months after therapy (n = 349) were selected to analyze fertility recovery; of these, patients with elevated FSH (> 10 U/L; n = 101) were followed until recovery. Factors predictive for therapy-related infertility were assessed by logistic regression. RESULTS The proportion of elevated FSH was 3% and 8% in patients treated with radiotherapy only or with nonalkylating chemotherapy (doxorubicin, bleomycin, vinblastine, dacarbazine [ABVD], epirubicin, bleomycin, vinblastine, prednisone [EBVP]); it was 60% (P < .001) after chemotherapy containing alkylating agents (mechlorethamine, vincristine, procarbazine, prednisone [MOPP], MOPP/doxorubicin, bleomycin, vinblastine [ABV], bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, prednisone [BEACOPP]). After a median time of 19 months, recovery of fertility occurred in 82% of patients treated without alkylating chemotherapy. This proportion was 30%, statistically (P < .001) lower in those treated with alkylating chemotherapy, and median time to recovery was 27 months. The post-treatment proportion of elevated FSH increased significantly (P < .001) with the dose of alkylating chemotherapy administered, and recovery was less frequent and slower after higher doses. Age more than 50 years and stage II disease also contributed to poor outcome. CONCLUSION Fertility can be secured after nonalkylating chemotherapy for Hodgkins lymphoma. In contrast, alkylating chemotherapy has a dismal effect, even after a limited number of cycles.


Hematological Oncology | 2010

Fertility preservation after chemotherapy for Hodgkin lymphoma

Marleen A.E. van der Kaaij; Jannie van Echten-Arends; Arnold Simons; Hanneke C. Kluin-Nelemans

Treatment for Hodgkin lymphoma can negatively affect fertility. This review summarizes data on fertility after chemotherapy in adult patients. Alkylating chemotherapy, especially if containing procarbazine and/or cyclophosphamide, is most harmful to gonadal functioning. Alkylating regimens cause prolonged azoospermia in 90–100% of men and ovarian failure in 5–25% of women under the age of 30. Non‐alkylating chemotherapy, like ABVD, is much less harmful: one‐third of male patients develop transient azoospermia, and almost no female patients experience ovarian failure. Age is an important factor for women: females over 30 years have a much higher risk of acute ovarian failure. However, with long‐term follow‐up the cumulative risk of menopause before the age of 40 becomes the same irrespective of treatment age. In males, semen cryopreservation before start of treatment should be offered to all (post)pubertal patients. For females with a partner, IVF followed by embryo cryopreservation is a widely available method, but this necessitates postponement of lymphoma therapy for at least a month. Oocyte cryopreservation and ovarian tissue cryopreservation are experimental techniques showing great promise. GnRH‐analogues are being investigated as possible means to preserve fertility in women, but effectiveness has not yet been proven conclusively. Copyright


European Journal of Obstetrics & Gynecology and Reproductive Biology | 2010

Perinatal outcome in singletons after modified natural cycle IVF and standard IVF with ovarian stimulation

M. J. Pelinck; Marjan H. Keizer; Annemieke Hoek; Arnold Simons; Karin Schelling; Karin J. Middelburg; M. J. Heineman

OBJECTIVE Singletons born after IVF treatment are at risk for adverse pregnancy outcome, the cause of which is unknown. The aim of the present study was to investigate the influence of ovarian stimulation on perinatal outcome. STUDY DESIGN In this single-centre retrospective study, perinatal outcome of singleton pregnancies resulting from IVF treatment with (n=106) and without ovarian stimulation (n=84) were compared. For IVF without ovarian stimulation, a modified natural cycle protocol was used. RESULTS No differences were found in pregnancy duration, proportion of prematurity and proportion of low birth weight. Mean birth weight of modified natural cycle vs standard IVF singletons was 3485 (+/-527) vs 3218 (+/-670)g; P=0.003. After adjustment for prognostic factors by linear regression analysis, the difference in birth weight remaining was 134 g; P=0.045. CONCLUSIONS Birth weights of modified natural cycle IVF singletons found in this study are higher than standard IVF singletons, suggesting that ovarian stimulation may be a causative factor in the occurrence of low birth weight in standard IVF.


Human Reproduction | 2008

Cumulative pregnancy rates after sequential treatment with modified natural cycle IVF followed by IVF with controlled ovarian stimulation

M. J. Pelinck; H. M. Knol; Niels E. A. Vogel; Eric Arts; Arnold Simons; M. J. Heineman; Annemieke Hoek

BACKGROUND In modified natural cycle IVF (MNC-IVF), treatment is aimed at using the one follicle that spontaneously develops to dominance, using a GnRH-antagonist together with gonadotrophins in the late follicular phase only. The MNC-IVF is of interest because of its low-risk and patient-friendly profile. The effect of application of MNC-IVF preceding standard IVF with ovarian stimulation on overall results is unknown. METHODS This single-center cohort study provides follow-up of an earlier study in which nine cycles of MNC-IVF were offered to 268 patients. Ongoing pregnancy rates and live birth rates, as well as time-to-pregnancy after controlled ovarian stimulation-IVF (COS-IVF) following MNC-IVF, were evaluated. RESULTS Actual observed cumulative ongoing pregnancy rates and live birth rates after sequential treatment with MNC-IVF followed by COS-IVF were 51.5 (95% CI: 45.4-57.6) and 50.0% (95% CI: 43.9-56.1) per patient, of which 8.0 and 6.7% were twins. Median time to ongoing pregnancy was 28.8 weeks. Including treatment-independent pregnancies, cumulative ongoing pregnancy rate was 56.7% (95% CI: 50.7-62.8). CONCLUSIONS Sequential treatment with MNC-IVF followed by COS-IVF does not appear to compromise overall success rates, while twin pregnancy rate is low. Because of its patient-friendly and low-risk profile, it seems appropriate to perform MNC-IVF preceding COS-IVF.


Human Reproduction | 2013

Modified natural cycle versus controlled ovarian hyperstimulation IVF: a cost-effectiveness evaluation of three simulated treatment scenarios

Henk Groen; Nino Tonch; Arnold Simons; Fulco van der Veen; Annemieke Hoek; Jolande A. Land

STUDY QUESTION Can modified natural cycle IVF or ICSI (MNC) be a cost-effective alternative for controlled ovarian hyperstimulation IVF or ICSI (COH)? SUMMARY ANSWER The comparison of simulated scenarios indicates that a strategy of three to six cycles of MNC with minimized medication is a cost-effective alternative for one cycle of COH with strict application of single embryo transfer (SET). WHAT IS KNOWN ALREADY MNC is cheaper per cycle than COH but also less effective in terms of live birth rate (LBR). However, strict application of SET in COH cycles reduces effectiveness and up to three MNC cycles can be performed at the same costs as one COH cycle. STUDY DESIGN, SIZE, DURATION The cost-effectiveness of MNC versus COH was evaluated in three simulated treatment scenarios: three cycles of MNC versus one cycle of COH with SET or double embryo transfer (DET) and subsequent transfer of cryopreserved embryos (Scenario 1); six cycles of MNC versus one cycle of COH with strictly SET and subsequent transfer of cryopreserved embryos (Scenario 2); six cycles of MNC with minimized medication (hCG ovulation trigger only) versus one cycle of COH with SET or DET and subsequent transfer of cryopreserved embryos (Scenario 3). We used baseline data obtained from two retrospective cohorts of consecutive patients (2005-2008) undergoing MNC in the University Medical Center Groningen (n = 499, maximum six cycles per patient) or their first COH cycle with subsequent transfer of cryopreserved embryos in the Academic Medical Center Amsterdam (n = 392). PARTICIPANTS/MATERIALS, SETTING, METHODS Data from 1994 MNC cycles (958 MNC-IVF and 1036 MNC-ICSI) and 392 fresh COH cycles (one per patient, 196 COH-IVF and 196 COH-ICSI) with subsequent transfer of cryopreserved embryos (n = 72 and n = 94 in MNC and COH cycles, respectively) in ovulatory, subfertile women <36 years of age served as baseline for the three simulated scenarios. To compare the scenarios, the incremental cost-effectiveness ratio (ICER) was calculated, defined as the ratio of the difference in IVF costs up to 6 weeks postpartum to the difference in LBR. Live birth was the primary outcome measure and was defined as the birth of at least one living child after a gestation of ≥25 weeks. MAIN RESULTS AND THE ROLE OF CHANCE In the baseline data, MNC was not cost-effective, as COH dominated MNC with a higher cumulative LBR (27.0 versus 24.0%) and lower cost per patient (€3694 versus €5254). The simulations showed that in scenario 1 three instead of six cycles lowered the costs of MNC to below the level of COH (€3390 versus €3694, respectively), but also lowered the LBR per patient (from 24.0 to 16.2%, respectively); Scenario 2: COH with strict SET was less effective than six cycles MNC (LBR 17.5 versus 24.0%, respectively), but also less expensive per patient (€2908) than MNC (€5254); Scenario 3: improved the cost-effectiveness of MNC but COH still dominated MNC when medication was minimized in terms of costs, i.e. €855 difference in favor of COH and 3% difference in LBR in favor of COH (ICER: €855/-3.0%). LIMITATIONS, REASONS FOR CAUTION Owing to the retrospective nature of the study, the analyses required some assumptions, for example regarding the costs of pregnancy and delivery, which had to be based on the literature rather than on individual data. Furthermore, costs of IVF treatment were based on tariffs and not on actual costs. Although this may limit the external generalizability of the results, the limitations will influence both treatments equally, and would therefore not bias the comparison of MNC versus COH. WIDER IMPLICATIONS OF THE FINDINGS The combined results suggest that MNC with minimized medication might be a cost-effective alternative for COH with strict SET. The scenarios reflect realistic alternatives for daily clinical practice. A preference for MNC depends on the willingness to trade off effectiveness in terms of LBR against the benefits of a milder stimulation regimen, including a very low rate of multiple pregnancies and hyperstimulation syndrome and ensuing lower costs per live birth. STUDY FUNDING/COMPETING INTEREST(S) The study was supported by research grants from Merck Serono and Ferring Pharmaceuticals. The authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER Not applicable.


Fertility and Sterility | 2010

Embryo quality and impact of specific embryo characteristics on ongoing implantation in unselected embryos derived from modified natural cycle in vitro fertilization

M. J. Pelinck; Annemieke Hoek; Arnold Simons; M. J. Heineman; Janny van Echten-Arends; Eus G. J. M. Arts

OBJECTIVE To study the implantation potential of unselected embryos derived from modified natural cycle IVF according to their morphological characteristics. DESIGN Cohort study. SETTING Academic department of reproductive medicine. PATIENT(S) A series of 449 single embryo transfers derived from modified natural cycle IVF. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Ongoing implantation rate according to embryo characteristics. RESULT(S) The best implantation was found in embryos with 4 and 8 cells on day 2 and 3 respectively, <or=10% fragmentation, and absence of multinucleated blastomeres. In contrast to findings from other studies, we found embryos with fewer than four blastomeres on day 2 to do relatively well. Furthermore, we found the implantation potential of embryos containing multinucleated blastomeres to be less severely impaired than expected. CONCLUSION(S) Findings from this study suggest that in currently used embryo scoring systems, the implantation potential of embryos with low numbers of blastomeres on day 2, as well as embryos containing multinucleated blastomeres, is underestimated. However, it is unclear whether the results of our study apply to embryos derived from controlled ovarian hyperstimulation cycles.


Journal of Clinical Oncology | 2011

Parenthood in Survivors of Hodgkin Lymphoma: An EORTC-GELA General Population Case-Control Study

Marleen A.E. van der Kaaij; Natacha Heutte; Paul Meijnders; Edwige Abeilard-Lemoisson; Michele Spina; Lotte C. Moser; Anouk Allgeier; Bart Meulemans; Brice Dubois; Arnold Simons; Pieternella J. Lugtenburg; Berthe M.P. Aleman; Evert M. Noordijk; Christophe Fermé; José Thomas; Aspasia Stamatoullas; Christophe Fruchart; Pauline Brice; Isabelle Gaillard; Jeanette K. Doorduijn; Catherine Sebban; Wilma G.J.M. Smit; Serge Bologna; Judith M. Roesink; Francisca Ong; Marc André; John Raemaekers; Michel Henry-Amar; Hanneke C. Kluin-Nelemans

PURPOSE We investigated the impact of Hodgkin lymphoma (HL) on parenthood, including factors influencing parenthood probability, by comparing long-term HL survivors with matched general population controls. PATIENTS AND METHODS A Life Situation Questionnaire was sent to 3,604 survivors treated from 1964 to 2004 in successive clinical trials. Responders were matched with controls (1:3 or 4) for sex, country, education, and year of birth (10-year groups). Controls were given an artificial date of start of treatment equal to that of their matched case. The main end point was presence of biologic children after treatment, which was evaluated by using conditional logistic regression analysis. Logistic regression analysis was used to analyze factors influencing spontaneous post-treatment parenthood. RESULTS In all, 1,654 French and Dutch survivors were matched with 6,414 controls. Median follow-up was 14 years (range, 5 to 44 years). After treatment, the odds ratio (OR) for having children was 0.77 (95% CI, 0.68 to 0.87; P < .001) for survivors compared with controls. Of 898 survivors who were childless before treatment, 46.7% achieved post-treatment parenthood compared with 49.3% of 3,196 childless controls (OR, 0.87; P = .08). Among 756 survivors with children before treatment, 12.4% became parents after HL treatment compared with 22.2% of 3,218 controls with children before treatment (OR, 0.49; P < .001). Treatment with alkylating agents, second-line therapy, and age older than 35 years at treatment appeared to reduce the chances of spontaneous post-treatment parenthood. CONCLUSION Survivors of HL had slightly but significantly fewer children after treatment than matched general population controls. The difference concerned only survivors who had children before treatment and appears to have more personal than biologic reasons. The chance of successful post-treatment parenthood was 76%.


Human Reproduction | 2015

Melanoma risk after ovarian stimulation for in vitro fertilization

M. Spaan; A.W. van den Belt-Dusebout; Michael Schaapveld; T.M. Mooij; Curt W. Burger; F.E. van Leeuwen; R. Schats; C.B. Lambalk; M. Kortman; J.S.E. Laven; C.A.M. Jansen; Frans M. Helmerhorst; B.J. Cohlen; D.D.M. Braat; J.M.J. Smeenk; Arnold Simons; F. van der Veen; J.L.H. Evers; P.A. van Dop

STUDY QUESTION Do women treated with ovarian stimulation for IVF have an increased risk of melanoma? SUMMARY ANSWER Ovarian stimulation for IVF does not increase risk of melanoma, even after a prolonged follow-up. WHAT IS KNOWN ALREADY Although exposure to ultraviolet radiation is the major risk factor for melanoma, associations between female sex steroids and melanoma risk have also been suggested. The results of available studies on fertility drugs and melanoma risk are inconclusive since most studies had several methodological limitations such as short follow-up, a small number of cases and no subfertile comparison group. STUDY DESIGN, SIZE, DURATION In 1996, a nationwide historic cohort study (the OMEGA-cohort) was established to examine the risk of cancer after ovarian stimulation for IVF. After a median follow-up of 17 years, cancer incidence was ascertained through linkage with the Netherlands Cancer Registry. Melanoma risk in the cohort was compared with that in the general population and between the IVF group and non-IVF group using multivariable Cox regression analyses. PARTICIPANTS/MATERIALS, SETTING, METHODS The cohort comprises 19 158 women who received IVF between 1983 and 1995 and a comparison group of 5950 women who underwent subfertility treatments other than IVF. Detailed IVF-treatment data were obtained from the medical records and complete information on parity and age at first birth was obtained through linkage with the Dutch Municipal Personal Records Database. MAIN RESULTS AND THE ROLE OF CHANCE In total, 93 melanoma cases were observed. The risk of melanoma was not elevated among IVF-treated women, neither when compared with the general population (standardized incidence ratio = 0.89; 95% confidence interval (CI): 0.69-1.12), nor when compared with the non-IVF group (adjusted hazard ratio (HR) = 1.27; 95% CI: 0.75-2.15). A higher number of IVF cycles was associated with apparent but statistically non-significant risk increases (5-6 cycles HR = 1.92; ≥7 cycles HR = 1.79). However, no significant trend emerged. In women with more follicle stimulating hormone/human menopausal gonadotrophin ampoules comparable non-significant risk increases were found. A longer follow-up did not increase melanoma risk. Nulliparous women did not have a significantly higher melanoma risk than parous women (HR = 1.22; 95% CI: 0.81-1.84). However, women who were 30 years of age or older at first birth had a significantly higher melanoma risk than women who were younger than 30 years at first birth (age: 30-34 years HR = 4.57; 95% CI: 2.07-10.08, >34 years HR = 2.98; 95% CI: 1.23-7.21). LIMITATIONS, REASONS FOR CAUTION Despite our large cohort, the number of melanoma cases was rather small, especially in our comparison group, which hampered subgroup analyses. WIDER IMPLICATIONS OF THE FINDINGS Our results are reassuring for women who underwent IVF or are contemplating to start IVF. Since our cohort study is one of the largest published so far, with long-term follow-up, a subfertile comparison group, and detailed IVF-treatment data, our results add important information to the available evidence. STUDY FUNDING/COMPETING INTEREST This study was supported by grants from the Dutch Cancer Society (NKI 2006-3631), the Health Research and Development Counsel (28-2540) and the Dutch Ministry of Health.

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Annemieke Hoek

University Medical Center Groningen

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M. J. Pelinck

University Medical Center Groningen

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M. J. Heineman

University Medical Center Groningen

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Niels E. A. Vogel

University Medical Center Groningen

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Eric Arts

University Medical Center Groningen

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Eus G. J. M. Arts

University Medical Center Groningen

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Hanneke C. Kluin-Nelemans

University Medical Center Groningen

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John Raemaekers

Radboud University Nijmegen

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