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Dive into the research topics where Frank J. Broekmans is active.

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Featured researches published by Frank J. Broekmans.


Fertility and Sterility | 2002

Predictors of poor ovarian response in in vitro fertilization: a prospective study comparing basal markers of ovarian reserve

L.F.J.M.M. Bancsi; Frank J. Broekmans; Marinus J.C. Eijkemans; Frank H. de Jong; J. Dik F. Habbema; Egbert R. te Velde

OBJECTIVE To identify and quantify predictors of poor ovarian response in in vitro fertilization (IVF). DESIGN; Prospective study. SETTING; Tertiary fertility center. PATIENT(S) One hundred twenty women undergoing their first IVF cycle. INTERVENTION(S) Measurement of the number of antral follicles and the total ovarian volume by ultrasound, and of basal levels of FSH, E(2), and inhibin B on cycle day 3. MAIN OUTCOME MEASURE(S) Ovarian response, and clinical and ongoing pregnancy rates. RESULT(S); The antral follicle count was the best single predictor for poor ovarian response: area under the receiver operating characteristic curve = 0.87. Addition of basal FSH and inhibin B levels to a logistic model with the antral follicle count significantly improved the prediction of poor response; the addition of basal E(2) levels and total ovarian volume did not improve the prediction. To express the discriminative performance of this model toward poor response, a maximum area under the receiver operating characteristic curve of 0.92 was calculated. Poor responders had significantly lower clinical and ongoing pregnancy rates than did normal responders. CONCLUSION(S) Our data demonstrate that the antral follicle count provides better prognostic information on the occurrence of poor response during hormone stimulation for IVF than does the patients chronological age and the currently used endocrine markers. However, endocrine tests remain informative. Multivariate models can achieve more accurate predictions of outcomes of complex events like ovarian response in IVF.


Fertility and Sterility | 2009

The role of antimullerian hormone in prediction of outcome after IVF: comparison with the antral follicle count

Simone L. Broer; Ben Willem J. Mol; Dave J. Hendriks; Frank J. Broekmans

OBJECTIVE To assess the value of antimullerian hormone (AMH) as a test to predict poor ovarian response and pregnancy occurrence after IVF and to compare it with the performance of the antral follicle count (AFC). DESIGN A systematic review of existing literature and a meta-analysis were carried out. After a comprehensive search, studies were included if 2 x 2 tables for outcomes poor response and pregnancy in IVF patients in relation to AMH or AFC could be constructed. SETTING Academic referral center for tertiary care. PATIENT(S) Cases indicated for IVF. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Poor response and nonpregnancy after IVF. RESULT(S) A total of 13 studies were found reporting on AMH and 17 on AFC. Because of heterogeneity among studies, calculation of a summary point estimate for sensitivity and specificity was not possible. However, for both tests summary receiver operating characteristic curves for the outcome measures poor response and nonpregnancy could be estimated and compared. The curves for the prediction of poor response indicated no significant difference between the performances of AMH and AFC. For the prediction of nonpregnancy, poor performance for both AMH and AFC was found. CONCLUSION(S) In this meta-analysis it was shown that AMH has at least the same level of accuracy and clinical value for the prediction of poor response and nonpregnancy as AFC.


Fertility and Sterility | 1999

Antral follicle counts by transvaginal ultrasonography are related to age in women with proven natural fertility

G.J. Scheffer; Frank J. Broekmans; Marinus Dorland; J.D.F. Habbema; Caspar W. N. Looman; Egbert R. te Velde

OBJECTIVE To investigate the relation between reproductive age and ultrasound (US)-based follicle counts and the reproducibility of follicle counts in regularly cycling women with proven fertility. DESIGN Prospective observational study. SETTING Tertiary fertility center. PATIENT(S) Healthy female volunteers with proven fertility, recruited by advertisement in local newspapers. INTERVENTION(S) The number of antral follicles sized 2-10 mm and ovarian volume were estimated by transvaginal US in the early follicular phase of the menstrual cycle in 162 women. A subgroup of 81 women underwent transvaginal US at several times in three subsequent cycles. MAIN OUTCOME MEASURE(S) Antral follicle count and total ovarian volume. RESULT(S) Women aged 25-46 years (n = 162) were studied. The relation of age with the US indices was computed after natural log transformation. Antral follicle count showed the clearest correlation with age (R = -0.67). A biphasic linear model gave the best fit to the data. Before the age of 37 years, the antral follicle count showed a mean yearly decline of 4.8%, compared with 11.7% thereafter. The reproducibility of the antral follicle count in two subsequent cycles was moderate. CONCLUSION(S) The number of small antral follicles in both ovaries as measured by US is clearly related to reproductive age and could well reflect the size of the remaining primordial follicle pool.


Menopause | 2004

Anti-Müllerian hormone is a promising predictor for the occurrence of the menopausal transition.

I.A.J. van Rooij; I. den Tonkelaar; Frank J. Broekmans; C.W.N. Looman; G.J. Scheffer; F.H. de Jong; Axel P. N. Themmen; E.R. te Velde

Objective: Age at menopause and age at the start of the preceding period of cycle irregularity (menopausal transition) show considerable individual variation. In this study we explored several markers for their ability to predict the occurrence of the transition to menopause. Design: A group of 81 normal women between 25 and 46 years of age visited the clinic two times (at T1 and T2) with an average interval of 4 years. All had a regular menstrual cycle pattern at T1. At T1, anti-müllerian hormone (AMH), follicle-stimulating hormone (FSH), inhibin B and estradiol (E2) were measured, and an antral follicle count (AFC) was made during the early follicular phase. At T2, information regarding cycle length and variability was obtained. Menopause transition was defined as a mean cycle length of less than 21 days or more than 35 days or as a mean cycle length of 21 to 35 days, but with the next cycle not predictable within 7 days during the last half year. A logistic regression analysis was performed, with the outcome measure as menopause transition. The area under the receiver operating curve (ROCAUC) was calculated as a measure of predictive accuracy. Results: In 14 volunteers, the cycle had become irregular at T2. Compared with women with a regular cycle at T2, these women were significantly older (median 44.7 vs 39.8 y, P < 0.001) and differed significantly in AFC, AMH, FSH, and inhibin B levels assessed at T1. All parameters with the exception of E2 were significantly associated with the occurrence of cycle irregularity; AMH, AFC, and age had the highest predictive accuracy (ROCAUC 0.87, 0.80, and 0.82, respectively). After adjusting for age, only AMH and inhibin B were significantly associated with cycle irregularity. Inclusion of inhibin B and age to AMH in a multivariable model improved the predictive accuracy (ROCAUC 0.92). Conclusions: The novel marker AMH is a promising predictor for the occurrence of menopausal transition within 4 years. Adding inhibin B improved the prediction. Therefore, AMH alone or in combination with inhibin B may well prove a useful indicator for the reproductive status of an individual woman.


Trends in Endocrinology and Metabolism | 2007

Female reproductive ageing: current knowledge and future trends

Frank J. Broekmans; Erik A. H. Knauff; Egbert R. te Velde; Nick S. Macklon; Bart C.J.M. Fauser

Over the past few decades, postponement of childbearing has led to a decrease in family size and increased rates of age-related female subfertility. Age-related decrease in ovarian follicle numbers and a decay in oocyte quality dictate the occurrence of natural loss of fecundity and, ultimately, menopause. The rate of this ovarian ageing process is highly variable among women. Identification of women who have severely decreased ovarian reserve for their age is, therefore, clinically relevant. Endocrine and imaging tests for ovarian reserve relate mainly to the quantitative aspect of ovarian reserve, but their capacity to predict the chances for pregnancy is limited. Genetic factors regulating the size of the follicle pool and the rate of its depletion might be identified in the near future and, possibly, assist the accurate prediction of a womans reproductive lifespan.


Human Reproduction | 2010

Comparison of inter- and intra-cycle variability of anti-Müllerian hormone and antral follicle counts

J. van Disseldorp; C.B. Lambalk; Janet Kwee; Caspar W. N. Looman; Marinus J.C. Eijkemans; B.C.J.M. Fauser; Frank J. Broekmans

BACKGROUND The antral follicle count (AFC) and anti-Müllerian hormone (AMH) both represent age-related follicular decline quite accurately, although long-term follow-up studies are still lacking. The best ovarian reserve test would need only a single, cycle-independent measurement to be representative. METHODS To compare the inter- and intra-cycle stability of AFC and AMH, we used age-adjusted intra-class correlation coefficients (ICCs). To measure inter-cycle stability across a number of up to four menstrual cycles, we used data, prospectively collected for the purpose of an other study, from 77 regularly cycling, infertile women aged 24-40 years. AMH and AFC values were measured on cycle day 3. To study intra-cycle variability, we used data from a prospective cohort study of 44 regularly cycling volunteers, aged 25-46 years and measured AMH and assessed the AFC (2-10 mm) every 1-3 cycle days. RESULTS Between menstrual cycles, AFC and AMH varied between 0 and 25 follicles (median 10), and 0.3 and 27.1 ng/ml (median 4.64). The difference in age-adjusted ICC between AMH [ICC, 0.89 (95% CI, 0.84-0.94)] and AFC [ICC, 0.71 (95% CI, 0.63-0.77)] was 0.18 (95% CI, 0.12-0.27). For the intra-cycle variation, 0-43 antral follicles (median 7) were counted per volunteer. The difference in age-adjusted ICC between AMH [ICC, 0.87 (95% CI, 0.82-0.91)] and AFC [ICC, 0.69 (95% CI, 0.46-0.82)] was 0.18 (95% CI, 0.034-0.42). CONCLUSIONS Serum AMH demonstrated less individual intra- and inter-cycle variation than AFCs and may therefore be considered a more reliable and robust means of assessing ovarian reserve in subfertile women.


The Journal of Clinical Endocrinology and Metabolism | 2008

Relationship of Serum Antimüllerian Hormone Concentration to Age at Menopause

J. van Disseldorp; Malcolm J. Faddy; Axel P. N. Themmen; F. H. de Jong; P.H.M. Peeters; Y. T. van der Schouw; Frank J. Broekmans

BACKGROUND Serum antimüllerian hormone (AMH) levels are highly correlated with antral follicle counts, while being menstrual cycle independent and easily measurable. However, AMH, unlike antral follicle counts, has not been tested as yet as a predictor of reproductive status. By relating AMH levels to the age distribution of reproductive events like onset of menopause, we tested this hypothesis. METHODS AMH levels were measured in 144 fertile normal volunteers and used to determine an estimate of mean AMH as a function of age. Data on the onset of menopause were obtained from the population-based Prospect-European Prospective Investigation into Cancer and Nutrition [Prospect-EPIC] cohort. Estimation of an AMH threshold to predict menopause was done by maximum likelihood using the observed (Prospect-EPIC) distribution of age at menopause and the predictive distribution from this AMH threshold. Predictions of age at menopause follow from an individual womans AMH relative to percentiles of the distribution of AMH for a given age, and the corresponding percentiles of the predictive distribution of age at menopause. RESULTS There was good conformity between the observed distribution of age at menopause and that predicted from declining AMH levels. CONCLUSIONS The similarity between observed and predictive distributions of age at menopause supports the hypothesis that AMH levels are related to onset of menopause. Results of this study suggest that AMH is able to specify a womans reproductive age more realistically than chronological age alone.


Human Reproduction | 2009

Anti-Müllerian hormone (AMH): what do we still need to know?

A. La Marca; Frank J. Broekmans; Annibale Volpe; B.C.J.M. Fauser; Nick S. Macklon

In the ovary, Anti-Müllerian hormone (AMH) is produced by the granulosa cells of early developing follicles and inhibits the transition from the primordial to the primary follicular stage. AMH levels can be measured in serum and have been shown to be proportional to the number of small antral follicles. In women serum AMH levels decrease with age and are undetectable in the post-menopausal period. In patients with premature ovarian failure AMH is undetectable or greatly reduced depending of the number of antral follicles in the ovaries. In contrast, AMH levels have been shown to be increased in women with polycystic ovary syndrome (PCOS). AMH levels appear to represent the quantity of the ovarian follicle pool and may become a useful marker of ovarian reserve. AMH measurement could also be useful in the prediction of the extremes of ovarian response to gonadotrophin stimulation for in vitro fertilization, namely poor- and hyper-response. Although AMH has the potential to increase our understanding of ovarian pathophysiology, and to guide clinical management in a broad range of conditions, a number of important questions relating to both the basic physiology of AMH and its clinical implications need to be answered.


Human Reproduction | 2008

Why do couples drop-out from IVF treatment? A prospective cohort study

M.F.G. Verberg; Marinus J.C. Eijkemans; E.M.E.W. Heijnen; Frank J. Broekmans; C. de Klerk; B.C.J.M. Fauser; Nick S. Macklon

BACKGROUND Cumulative IVF pregnancy rates are compromised by the large number of couples who drop-out of treatment before achieving pregnancy. The aim of this study was to identify the role of the treatment strategy applied, and potential other factors that influence the decision of couples to discontinue treatment. METHODS The incidence of drop-out from IVF treatment and factors related to drop-out were studied in a cohort of IVF patients aged <38 years embarking on IVF treatment either with a mild or a standard treatment strategy for a planned maximum number of treatment cycles. RESULTS Of the 384 couples studied, 17% dropped out of IVF treatment. The physical or psychological burden of treatment was the most frequent cause of drop-out (28%). The application of a mild treatment strategy (mild ovarian stimulation along with the transfer of a single embryo) significantly reduced the chance of drop-out (hazard ratio (HR) 0.55; 95% confidence interval (CI), 0.31-0.96). When a mild IVF strategy was employed, the association between the baseline anxiety score and drop-out was reduced by >50%. The presence of severe male subfertility (HR 4.80; 95% CI, 1.63-14.13) and the failure to achieve embryo transfer (odds ratio 0.41; 95% CI, 0.24-0.72) were also related to drop-out. CONCLUSIONS Reducing drop-out rate is crucial to further improve the efficacy and cost-effectiveness of IVF treatment. An important factor determining the risk of drop-out is the burden of the treatment strategy. The application of a mild treatment strategy and managing patients expectations might reduce drop-out rates.


Human Reproduction Update | 2013

Added value of ovarian reserve testing on patient characteristics in the prediction of ovarian response and ongoing pregnancy: an individual patient data approach

Simone L. Broer; J. van Disseldorp; K.A. Broeze; Madeleine Dólleman; B.C. Opmeer; P. Bossuyt; Marinus J.C. Eijkemans; B.W. Mol; Frank J. Broekmans; Richard A. Anderson; M. Ashrafi; L.F.J.M.M. Bancsi; Ettore Caroppo; A.B. Copperman; T. Ebner; M. Eldar Geva; M. Erdem; E.M. Greenblatt; K. Jayaprakasan; R. Fenning; E. R. Klinkert; Janet Kwee; C.B. Lambalk; A. La Marca; M. McIlveen; L.T. Merce; Shanthi Muttukrishna; Scott M. Nelson; H.Y. Ng; B. Popovic-Todorovic

BACKGROUND Although ovarian reserve tests (ORTs) are frequently used prior to IVF treatment for outcome prediction, their added predictive value is unclear. We assessed the added value of ORTs to patient characteristics in the prediction of IVF outcome. METHODS An individual patient data (IPD) meta-analysis from published studies was performed. Studies on FSH, anti-Müllerian hormone (AMH) or antral follicle count (AFC) in women undergoing IVF were identified and authors were contacted. Using random intercept logistic regression models, we estimated the added predictive value of ORTs for poor response and ongoing pregnancy after IVF, relative to patient characteristics. RESULTS We were able to collect 28 study databases, comprising 5705 women undergoing IVF. The area under the receiver-operating characteristic curve (AUC) for female age in predicting poor response was 0.61. AFC and AMH each significantly improved the model fit (P-value <0.001). Moreover, almost a similar accuracy was reached using AMH or AFC alone (AUC 0.78 and 0.76, respectively). Combining the two tests, however, did not improve prediction (AUC 0.80, P = 0.19) of poor response. In predicting ongoing pregnancy after IVF, age was the best single predictor (AUC 0.57), and none of the ORTs added any value. CONCLUSIONS This IPD meta-analysis demonstrates that AFC and AMH clearly add to age in predicting poor response. As single tests, AFC and AMH both fully cover the prediction of poor ovarian response. In contrast, none of the ORTs add any information to the limited capacity of female age to predict ongoing pregnancy after IVF. The clinical usefulness of ORTs prior to IVF will be limited to the prediction of ovarian response.

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Annemieke Hoek

University Medical Center Groningen

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Joop S.E. Laven

Erasmus University Rotterdam

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Cornelis B. Lambalk

VU University Medical Center

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