Nicole G.M. Beckers
Erasmus University Rotterdam
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Featured researches published by Nicole G.M. Beckers.
Fertility and Sterility | 2002
Nicole G.M. Beckers; Nick S. Macklon; Marinus J.C. Eijkemans; Bart C.J.M. Fauser
OBJECTIVE To investigate whether follicular phase characteristics associated with ovarian aging can be observed in women of normal reproductive age, who had previously shown a poor response to ovarian hyperstimulation for IVF. DESIGN Observational, prospective study. SETTING Tertiary fertility center. PATIENT(S) Eleven regularly cycling, ovulatory women, aged 29-40 years who previously presented with fewer than four dominant follicles after ovarian hyperstimulation for IVF. INTERVENTION(S) Frequent serum hormone assessments and transvaginal ultrasound during the follicular phase of a spontaneous, unstimulated cycle. MAIN OUTCOME MEASURE(S) Duration of the follicular phase; serum LH, FSH, E(2), P, inhibin A, and inhibin B levels; and number of antral follicles observed by ultrasound. Results were compared with the cycle characteristics of a reference population of 38 healthy normo-ovulatory women aged 20-36 years (as published elsewhere). RESULT(S) Poor responders had significantly fewer antral follicles than controls. Median FSH concentrations were significantly higher compared with controls, but the majority had FSH levels within the normal range. Follicular phase P levels were significantly higher in poor responders. Duration of the follicular phase, E(2), and inhibin A and inhibin B serum levels did not differ between poor responders and controls. CONCLUSION(S) Normo-ovulatory regularly cycling women with a previous poor response to ovarian hyperstimulation for IVF show follicular phase characteristics suggestive of ovarian aging.
Human Reproduction | 2009
Jolanda C. Boxmeer; Nick S. Macklon; Jan Lindemans; Nicole G.M. Beckers; Marinus J.C. Eijkemans; Joop S.E. Laven; Eric A.P. Steegers; Régine P.M. Steegers-Theunissen
BACKGROUND Maternal hyperhomocysteinemia is detrimental for reproduction, but the effects on embryo quality are unknown. The aim of this study was to investigate whether biomarkers of the homocysteine pathway are associated with in vitro fertilization (IVF) outcome. METHODS In a prospective study, we investigated biomarkers of the homocysteine pathway for associations with embryo quality and biochemical pregnancy in women undergoing IVF or intracytoplasmic sperm injection treatment (n = 181). In the treatment cycle, blood and monofollicular fluid samples were collected for determination of folate, cobalamin and total homocysteine (tHcy) concentrations. RESULTS Of all the women in the study, 67% used folic acid supplements. In blood, a significant correlation was established between high cobalamin and better embryo quality [standardized adjusted regression coefficient: -0.17, 95% confidence interval (CI): -0.30, -0.01]. In monofollicular fluid of non-supplemented women, high cobalamin correlated with better embryo quality (estimate: -0.87; 95% CI: -1.68, -0.06), whereas high tHcy resulted in poor embryo quality (estimate: 1.01; 95% CI: 0.08, 1.95). However, in monofollicular fluid of supplemented women, high tHcy correlated with better embryo quality (estimate: -0.58; 95% CI: -1.12, -0.04). In the total group, a 2-fold increase of monofollicular fluid folate corresponded with a 3.3 times higher chance (95% CI: 1.09, 9.71) of achieving pregnancy. CONCLUSIONS An optimal homocysteine pathway in follicular fluid is associated with a better embryo quality and chance of pregnancy.
Fertility and Sterility | 2003
Nicole G.M. Beckers; Nick S. Macklon; Paul Devroey; Peter Platteau; Peter J Boerrigter; Bart C.J.M. Fauser
OBJECTIVE To report the first pregnancy and live birth after ovarian stimulation using a chimeric long-acting human recombinant FSH agonist (recFSH-CTP) for IVF. DESIGN Case report. SETTING Tertiary fertility center. PATIENT(S) A 32-year-old woman with a 7-year history of primary infertility. INTERVENTION(S) Ovarian stimulation with a single SC injection of 180 microg recFSH-CTP on cycle day 3, followed by daily injections of 150 IU recFSH from cycle day 10 onward, combined with daily GnRH antagonist 0.25 mg SC to prevent a premature LH rise. Final oocyte maturation was induced by 10,000 IU hCG. MAIN OUTCOME MEASURE(S) First ongoing pregnancy obtained with recFSH-CTP. RESULT(S) Twelve oocytes were retrieved. Ten oocytes were fertilized in vitro by intracytoplasmic sperm injection, and from these 10 oocytes, two embryos were subsequently transferred after 3 days of culture. A pregnancy test 2 weeks after ET was positive, and ultrasound investigation revealed an intact, intrauterine, singleton pregnancy after 12 weeks. CONCLUSION(S) The first pregnancy and live birth was achieved after ovarian stimulation using recFSH-CTP for IVF.
Journal of Assisted Reproduction and Genetics | 2002
D. de Jong; Marinus J.C. Eijkemans; Nicole G.M. Beckers; R. V. Pruijsten; B.C.J.M. Fauser; Nick S. Macklon
AbstractPurpose: To calculate the added benefit of a cryopreservation program to the cumulative ongoing pregnancy rate over a maximum of three cycles of IVF. Methods: A total of 1251 couples beginning their first IVF treatment between January 1995 and December 1999 were evaluated. Ongoing pregnancies from fresh and subsequent cryopreserved embryo transfer cycles were analyzed. Pregnancies arising from the cryopreservation cycle were considered to augment the cumulative pregnancy rate when no ongoing pregnancy arose from the fresh embryo transfer cycle. Results: The ongoing pregnancy rate per cryopreserved embryo transfer was 11.7%. The cumulative ongoing pregnancy rate following three successive started fresh IVF cycles was 42.5%. When pregnancies arising from the transfer of thawed cryopreserved embryos were included, the cumulative ongoing pregnancy rate increased to 43.8%, rising to 44.8% when extrapolated data from as yet unthawed embryos was included. Conclusions: When analyzed in these terms, the supplementary benefit of cryopreserving supranumerical embryos appears limited.
Reproductive Biomedicine Online | 2002
M. H. van der Gaast; Nicole G.M. Beckers; K. Beier-Hellwig; Henning M. Beier; Nick S. Macklon; B.C.J.M. Fauser
The contemporary approach to ovarian stimulation for IVF treatment results in supraphysiological concentrations of steroids during the follicular and luteal phases of the menstrual cycle. These sex steroids act directly and indirectly to mature the endometrium, influencing receptivity for implantation. Corpus luteum function is distinctly abnormal in IVF cycles, and therefore luteal support is widely used. Various reasons may underlie the defective luteal phase, including (i) ovarian hyperstimulation per se, (ii) gonadotrophin-releasing hormone (GnRH) analogue co-treatment and (iii) the use of human chorionic gonadotrophin (HCG) to induce final oocyte maturation. The recent introduction of GnRH antagonist co-treatment for the prevention of a premature LH rise during the late follicular phase allows for different approaches to ovarian stimulation for IVF. However, a recent meta-analysis showed that implantation rates may be compromised by using GnRH antagonists in currently employed regimens. The development of endometrium receptive to embryo implantation is a complex process and may be altered by inappropriate exposure to sex steroids in terms of timing, duration and magnitude. New approaches to the assessment of endometrial receptivity are now required. Novel approaches to ovarian stimulation aimed at adjusted GnRH antagonist regimens and achieving a more physiological luteal phase endocrinology are now appearing in the literature and may represent an important step in the improvement of the overall health economics of IVF.
The Journal of Clinical Endocrinology and Metabolism | 2011
John M. Twigt; Fatima Hammiche; Kevin D. Sinclair; Nicole G.M. Beckers; Jenny A. Visser; Jan Lindemans; Frank H. de Jong; Joop S.E. Laven; Régine P.M. Steegers-Theunissen
BACKGROUND Folate is a methyl donor. Availability of folate affects DNA methylation profiles and thereby gene expression profiles. We investigated the effects of low-dose folic acid use (0.4 mg/d) on the ovarian response to mild and conventional ovarian stimulation in women. METHODS In a randomized trial among subfertile women, 24 and 26 subjects received conventional and mild ovarian stimulation, respectively. Blood samples were taken during the early follicular phase of the cycle prior to treatment and on the day of human chorionic gonadotropin administration for determination of serum total homocysteine, anti-Müllerian hormone (AMH), estradiol, and folate. Folic acid use was validated by questionnaire and serum folate levels. Preovulatory follicles were visualized, counted, and diameters recorded using transvaginal ultrasound. The relation between folic acid use and ovarian response was assessed using linear regression analysis. RESULTS Folic acid use modified the ovarian response to ovarian stimulation treatment. The estradiol response was higher in nonfolic acid users receiving conventional treatment [β(interaction) = 0.52 (0.07-0.97); P = 0.03], and this effect was independent of serum AMH levels and the preovulatory follicle count. In the conventional treatment, the mean follicle number was also greater in nonusers compared with the users group (14.1 vs. 8.9, P = 0.03). CONCLUSION Low-dose folic acid use attenuates follicular and endocrine responses to conventional stimulation, independent of AMH and follicle count. The nature of this observation suggests that the effect of folic acid is most prominent during early follicle development, affecting immature follicles. Deleterious effects of folate deficiency, like DNA hypomethylation and oxidative stress, can help to explain our observations.
Reproductive Biomedicine Online | 2014
Minouche M.E. van Rumste; Inge M. Custers; Madelon van Wely; Carolien A. M. Koks; Hans G.I. van Weering; Nicole G.M. Beckers; G.J. Scheffer; Frank J. Broekmans; Peter G.A. Hompes; M.H. Mochtar; Fulco van der Veen; Ben Willem J. Mol
Couples with unexplained subfertility are often treated with intrauterine insemination (IUI) with ovarian stimulation, which carries the risk of multiple pregnancies. An explorative randomized controlled trial was performed comparing one cycle of IVF with elective single-embryo transfer (eSET) versus three cycles of IUI-ovarian stimulation in couples with unexplained subfertility and a poor prognosis for natural conception, to assess the economic burden of the treatment modalities. The main outcome measures were ongoing pregnancy rates and costs. This study randomly assigned 58 couples to IVF-eSET and 58 couples to IUI-ovarian stimulation. The ongoing pregnancy rates were 24% in with IVF-eSET versus 21% with IUI-ovarian stimulation, with two and three multiple pregnancies, respectively. The mean cost per included couple was significantly different: €2781 with IVF-eSET and €1876 with IUI-ovarian stimulation (P<0.01). The additional costs per ongoing pregnancy were €2456 for IVF-eSET. In couples with unexplained subfertility, one cycle of IVF-eSET cost an additional €900 per couple compared with three cycles of IUI-ovarian stimulation, for no increase in ongoing pregnancy rates or decrease in multiple pregnancies. When IVF-eSET results in higher ongoing pregnancy rates, IVF would be the preferred treatment. Couples that have been trying to conceive unsuccessfully are often treated with intrauterine insemination (IUI) and medication to improve egg production (ovarian stimulation). This treatment carries the risk of multiple pregnancies like twins. We performed an explorative study among those couples that had a poor prognosis for natural conception. One cycle of IVF with transfer of one selected embryo (elective single-embryo transfer, eSET) was compared with three cycles of IUI-ovarian stimulation. The aim of this study was to assess the economic burden of both treatments. The Main outcome measures were number of good pregnancies above 12weeks and costs. We randomly assigned 58 couples to IVF-eSET and 58 couples to IUI-ovarian stimulation. The ongoing pregnancy rates were comparable: 24% with IVF-eSET versus 21% with IUI-ovarian stimulation. There were two multiple pregnancies with IVF-eSET and three multiple pregnancies with IUI-ovarian stimulation. The mean cost per included couple was significantly different, €2781 with IVF-eSET and €1876 with IUI-ovarian stimulation. The additional costs per ongoing pregnancy were €2456 for IVF-eSET. In couples with unexplained subfertility, one cycle of IVF-eSET costed an additional €900 per couple compared to three cycles of IUI-ovarian stimulation, for no increase in ongoing pregnancy rates or decrease in multiple pregnancies. We conclude that IUI-ovarian stimulation is the preferred treatment to start with. When IVF-eSET results in a higher ongoing pregnancy rate (>38%), IVF would be the preferred treatment.
Journal of Assisted Reproduction and Genetics | 1999
Nicole G.M. Beckers; Math H. E. C. Pieters; Liliana Ramos; Gerard H. Zeilmaker; Bart C.J.M. Fauser; Didi D. M. Braat
Purpose:Our purpose was to determine whether immature oocytes could be retrieved under local anesthesia, whether these oocytes would mature and fertilize in vitro, and whether adequate endometrium development could be obtained after hormonal supplementation.Methods:Ovum pick-up was performed under local anesthesia. Immature oocytes were cultured and inseminated. To prepare the endometrium, estradiolvalerate was administered in combination with micronized progesterone.Results:Immature oocytes were obtained in all cases. Fifty-six percent (n = 30) of the oocytes developed into metaphase II (MII) after 48 hr of culture, and another 20% reached the MII stage by 72 hr. Normal fertilization was observed in only 10% of oocytes inseminated. No embryonic development occurred, and therefore embryo transfer was not performed in any of the patients. Endometrial microbiopsy was performed in all subjects and endometrial development was considered sufficient in eight patients.Conclusions:We collected immature oocytes from patients with polycystic ovary syndrome without general anesthesia. In vitro maturation of these oocytes seemed adequate but fertilization rates were poor. Sufficient endometrial quality was obtained after hormonal substitution.
Human Reproduction | 2007
Esther B. Baart; Elena Martini; Marinus J.C. Eijkemans; Diane Van Opstal; Nicole G.M. Beckers; Arie Verhoeff; Nick S. Macklon; Bart C.J.M. Fauser
The Lancet | 2007
E.M.E.W. Heijnen; Marinus J.C. Eijkemans; Cora de Klerk; Suzanne Polinder; Nicole G.M. Beckers; Ellen R. Klinkert; Frank J. Broekmans; Jan Passchier; Egbert R. te Velde; Nick S. Macklon; Bart C.J.M. Fauser