J.G. Bentzen
Copenhagen University Hospital
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Human Reproduction Update | 2012
Lone Schmidt; T. Sobotka; J.G. Bentzen; A. Nyboe Andersen
BACKGROUND Across the developed world couples are postponing parenthood. This review assesses the consequences of delayed family formation from a demographic and medical perspective. One main focus is on the quantitative importance of pregnancy postponement. METHODS Medical and social science databases were searched for publications on relevant subjects such as delayed parenthood, female and male age, fertility, infertility, time to pregnancy (TTP), fetal death, outcome of medically assisted reproduction (MAR) and mental well-being. RESULTS Postponement of parenthood is linked to a higher rate of involuntary childlessness and smaller families than desired due to increased infertility and fetal death with higher female and male age. For women, the increased risk of prolonged TTP, infertility, spontaneous abortions, ectopic pregnancies and trisomy 21 starts at around 30 years of age with a more pronounced effects >35 years, whereas the increasing risk of preterm births and stillbirths starts at around 35 years with a more pronounced effect >40 years. Advanced male age has an important but less pronounced effect on infertility and adverse outcomes. MAR treatment cannot overcome the age-related decline in fecundity. CONCLUSIONS In general, women have partners who are several years older than themselves and it is important to focus more on the combined effect of higher female and male age on infertility and reproductive outcome. Increasing public awareness of the impact of advanced female and male age on the reproductive outcome is essential for people to make well-informed decisions on when to start family formation.
Human Reproduction | 2014
Mette Petri Lauritsen; J.G. Bentzen; Anja Pinborg; A. Loft; Julie Lyng Forman; L.L. Thuesen; Arieh Cohen; David M. Hougaard; A. Nyboe Andersen
STUDY QUESTION What is the prevalence in a normal population of polycystic ovary syndrome (PCOS) according to the Rotterdam criteria versus revised criteria including anti-Müllerian hormone (AMH)? SUMMARY ANSWER The prevalence of PCOS was 16.6% according to the Rotterdam criteria. When replacing the criterion for polycystic ovaries by antral follicle count (AFC) > 19 or AMH > 35 pmol/l, the prevalence of PCOS was 6.3 and 8.5%, respectively. WHAT IS KNOWN ALREADY?: The Rotterdam criteria state that two out of the following three criteria should be present in the diagnosis of PCOS: oligo-anovulation, clinical and/or biochemical hyperandrogenism and polycystic ovaries (AFC ≥ 12 and/or ovarian volume >10 ml). However, with the advances in sonography, the relevance of the AFC threshold in the definition of polycystic ovaries has been challenged, and AMH has been proposed as a marker of polycystic ovaries in PCOS. STUDY DESIGN, SIZE, DURATION From 2008 to 2010, a prospective, cross-sectional study was performed including 863 women aged 20-40 years and employed at Copenhagen University Hospital, Rigshospitalet, Denmark. PARTICIPANTS/MATERIAL, SETTING, METHODS We studied a subgroup of 447 women with a mean (±SD) age of 33.5 (±4.0) years who were all non-users of hormonal contraception. Data on menstrual cycle disorder and the presence of hirsutism were obtained. On cycle Days 2-5, or on a random day in the case of oligo- or amenorrhoea, sonographic and endocrine parameters were measured. MAIN RESULTS AND THE ROLE OF CHANCE The prevalence of PCOS was 16.6% according to the Rotterdam criteria. PCOS prevalence significantly decreased with age from 33.3% in women < 30 years to 14.7% in women aged 30-34 years, and 10.2% in women ≥ 35 years (P < 0.001). In total, 53.5% fulfilled the criterion for polycystic ovaries with a significant age-related decrease from 69.0% in women < 30 years to 55.8% in women aged 30-34 years, and 42.8% in women ≥ 35 years (P < 0.001). AMH or age-adjusted AMH Z-score was found to be a reliable marker of polycystic ovaries in women with PCOS according to the Rotterdam criteria [area under the curve (AUC) 0.994; 95% confidence interval (CI): 0.990-0.999] and AUC 0.992 (95% CI: 0.987-0.998), respectively], and an AMH cut-off value of 18 pmol/l and AMH Z-score of -0.2 showed the best compromise between sensitivity (91.8 and 90.4%, respectively) and specificity (98.1 and 97.9%, respectively). In total, AFC > 19 or AMH > 35 occurred in 17.7 and 23.0%, respectively. The occurrence of AFC > 19 or AMH > 35 in the age groups < 30, 30-34 and ≥ 35 years was 31.0 and 35.7%, 18.8 and 21.3%, and 9.6 and 18.7%, respectively. When replacing the Rotterdam criterion for polycystic ovaries by AFC > 19 or AMH > 35 pmol/l, the prevalence of PCOS was 6.3 or 8.5%, respectively, and in the age groups < 30, 30-34 and ≥ 35 years, the prevalences were 17.9 and 22.6%, 3.6 and 5.6%, and 3.6 and 4.8%, respectively. LIMITATIONS, REASON FOR CAUTION The participants of the study were all health-care workers, which may be a source of selection bias. Furthermore, the exclusion of hormonal contraceptive users from the study population may have biased the results, potentially excluding women with symptoms of PCOS. WIDER IMPLICATIONS OF THE FINDINGS AMH may be used as a marker of polycystic ovaries in PCOS. However, future studies are needed to validate AMH threshold levels, and AMH Z-score may be appropriate to adjust for the age-related decline in the AFC. STUDY FUNDING/COMPETING INTEREST(S) None. TRIAL REGISTRATION NUMBER Not applicable.
Reproductive Biomedicine Online | 2012
J.G. Bentzen; Julie Lyng Forman; Anja Pinborg; Øjvind Lidegaard; Elisabeth C. Larsen; L. Friis-Hansen; Th Johannsen; A. Nyboe Andersen
It remains controversial whether anti-Müllerian hormone (AMH) concentration is influenced by hormonal contraception. This study quantified the effect of hormonal contraception on both endocrine and sonographic ovarian reserve markers in 228 users and 504 non-users of hormonal contraception. On day 2-5 of the menstrual cycle or during withdrawal bleeding, blood sampling and transvaginal sonography was performed. After adjusting for age, ovarian reserve parameters were lower among users than among non-users of hormonal contraception: serum AMH concentration by 29.8% (95% CI 19.9 to 38.5%), antral follicle count (AFC) by 30.4% (95% CI 23.6 to 36.7%) and ovarian volume by 42.2% (95% CI 37.8 to 46.3%). AFC in all follicle size categories (small, 2-4 mm; intermediate, 5-7 mm; large, 8-10 mm) was lower in users than in non-users of hormonal contraception. A negatively linear association was observed between duration of hormonal-contraception use and ovarian reserve parameters. No dose-response relation was found between the dose of ethinyloestradiol and AMH or AFC. This study indicates that ovarian reserve markers are lower in women using sex steroids for contraception. Thus, AMH concentration and AFC may not retain their accuracy as predictors of ovarian reserve in women using hormonal contraception. Serum anti-Müllerian hormone (AMH) concentration is an indirect marker of the number of small follicles in the ovary and thereby the ovarian reserve. The AMH concentration is now widely used as one of the markers of the ovarian reserve in ovarian hormonal stimulation regimens. Hence the AMH concentration in a patient is used to decide the dose of the ovarian hormonal stimulation prior to IVF treatment. In some infertile patients, hormonal contraception is used prior to ovarian hormonal stimulation and therefore it is important to clarify whether serum AMH concentration is influenced by the use of sex steroids. The aim of this study was to quantify the potential effect of hormonal contraception on the ovarian function by hormonal analyses and ovarian ultrasound examination. Examinations were performed in the early phase of the menstrual cycle or the hormone-free interval of hormonal contraception. We compared the AMH concentration, the antral follicle count (AFC) and the ovarian volume in 228 users versus 504 non-users of hormonal contraception. Users of hormonal contraception had 29.8% lower AMH concentration, 30.4% lower AFC and 42.2% lower ovarian volume than non-users. These findings were more pronounced with increasing duration of hormonal contraception. No dose-response relation was found between the dose of ethinylestradiol and the impact on serum AMH and AFC. The study indicates that ovarian reserve markers are lower in women using sex steroids for contraception. Thus, serum AMH concentration and AFC may not retain their accuracy as predictors of the ovarian reserve in women using hormonal contraception.
The Journal of Clinical Endocrinology and Metabolism | 2013
J.G. Bentzen; Julie Lyng Forman; Trine Holm Johannsen; Anja Pinborg; Elisabeth C. Larsen; A. Nyboe Andersen
CONTEXT The interindividual variation in the age-related decline of ovarian follicles is wide. Hence, it is important to identify reliable, sensitive, and specific markers to assess the ovarian reserve of the individual woman. OBJECTIVE The aim of this study was to characterize the relation between age and ovarian reserve parameters in a population of healthy women with regular menstrual cycle. DESIGN AND SETTING We conducted a prospective, population-based, cross-sectional study. PARTICIPANTS A total of 366 health care workers aged 21-41 years employed at a University Hospital were included. INTERVENTIONS There were no interventions. MAIN OUTCOME MEASURES Serum anti-Müllerian hormone (AMH) concentration, antral follicle count (AFC), antral follicle size categories (small: 2-4 mm; intermediate: 5-7 mm; and large: 8-10 mm), and ovarian volume were measured. RESULTS Serum AMH level declined by 5.6% per year (95% confidence interval 3.7-7.4%, P < .001), AFC (2-10 mm) declined by 4.4% per year (3.2-5.7%, P < .001), and ovarian volume declined by 1.1% per year (0.2-2.0, P = .002), respectively. The mean proportion of small follicles decreased with age (P = .04), the proportion of intermediate follicles displayed no significant change with age (P = .58), and the mean proportion of large follicles increased with age (P < .001). The prevalence of large follicles increased with decreasing serum AMH concentration [odds ratio 1.04 per 1 pmol/L (1.02-1.06), P < .001, area under the curve 0.66], and with decreasing total AFC [odds ratio 1.04 per follicle (1.02-1.05), P < .001, area under the curve 0.62]. CONCLUSION Chronological age was inversely related to serum AMH concentration, total AFC, and ovarian volume. Subclasses of AFC sized 2-4 and 5-7 mm decreased with increasing age, whereas AFC sized 8-10 mm increased with increasing age. Within AFC, a shift toward larger follicles with increasing age was observed. The occurrence of large follicles was more strongly related to biological age in terms of AMH and AFC than chronological age.
Reproductive Biomedicine Online | 2013
S.N. Nielsen; Anders Nyboe Andersen; Kirsten Tryde Schmidt; Catherine Rechnitzer; Kjeld Schmiegelow; J.G. Bentzen; Elisabeth C. Larsen
Previously, this study group found that female childhood cancer survivors could be at risk of early cessation of fertility. The aim of the present study was to evaluate reproductive function in the same group of survivors 10 years after the initial study. Of the original cohort of 100, 71 were re-examined. Thirty-six survivors reported regular menstrual cycles. When they were compared with 210 controls, they differed significantly in antral follicle count (AFC) (median 15 versus 18, P=0.047) but not in anti-Müllerian hormone (AMH) (median 13.0 versus 17.8 pmol/l). Survivors cured with minimal gonadotoxic treatment had significantly higher AMH and AFC compared with survivors cured with either potentially gonadotoxic treatment or treatment including alkylating chemotherapy and ovarian irradiation (20.0, 5.8 and <3 pmol/l, P<0.001; and 15, 9 and 2, P=0.03, respectively). Thirty-eight survivors had achieved at least one live birth. Complicated second-trimester abortions (n=4) were observed primarily in survivors cured with radiotherapy affecting pelvic organs. In conclusion, childhood cancer survivors have signs of diminished ovarian reserve. However, if the ovarian function is preserved in the early to mid-twenties, it is likely to persist until the mid-thirties, giving a good chance of childbearing.
The European Journal of Contraception & Reproductive Health Care | 2012
Luise Lermark Mortensen; Hanne Kristine Hegaard; Anders Nyboe Andersen; J.G. Bentzen
ABSTRACT Objective To explore attitudes towards family formation and fertility awareness among Danish female healthcare professionals. Methods We collected cross-sectional baseline data from a prospective cohort study of 863 women, ranging in age from 20 to 40 years, working at a hospital in Denmark. Information about participants’ intentions and attitudes towards family formation and fertility knowledge was gathered by means of a questionnaire. Results Only 2% of the respondents did not want children. Most women believed that motherhood is important, and hoped to have two to three children. About half of the respondents intended to have their last child after the age of 35 years. The most important prerequisites for family formation included: living in a stable relationship, having completed ones studies, a sound financial situation, a job that can be kept when having children, access to public child day care, and the possibility of travelling. As many as 50% of women underrated the impact of a womans age on fertility, and overestimated the success rates of assisted reproductive technology (ART) treatments. Conclusions Many female healthcare professionals contemplated giving birth after the age of 35 years. Knowledge of fertility and ART success rates is needed to make well-informed decisions about when to have children.
Reproductive Biomedicine Online | 2018
Anne-Sofie Korsholm; Kathrine Birch Petersen; J.G. Bentzen; Linda Hilsted; Anders Nyboe Andersen; Helene Westring Hvidman
The objectives of this study were to investigate whether anti-Müllerian hormone (AMH) concentrations can predict pregnancy rates and time to pregnancy (TTP) in women attempting to conceive naturally/having an unplanned conception, and whether there is a lower AMH threshold compatible with natural conception. This prospective cohort study included 260 women aged 25-42 years in two subcohorts: (A) healthcare workers at Rigshospitalet (2008-2010), and (B) women consulting the Fertility Assessment and Counselling Clinic (2011-2014), Rigshospitalet, Denmark. Pregnancy rates and TTP at 2-year follow-up were stratified into AMH groups: low: < 9.5 pmol/l, intermediate: 9.5-33 pmol/l, high: > 33 pmol/l. Pregnancy rates increased with increasing AMH: 60.1% (low) versus 70.0% (intermediate) versus 78.3% (high) (P = 0.03). The highest pregnancy rate (84.1%) was seen in regular cycling women with high AMH. TTP was reduced in women with high AMH compared with intermediate or low AMH (stepwise trend test P = 0.01). Natural conceptions were observed with AMH concentrations down to 1.2 pmol/l. In conclusion, high AMH, especially in ovulatory women, was associated with higher pregnancy rates. Nonetheless, TTP reflected a large variation in fecundity within similar AMH concentrations and natural conceptions occurred with AMH down to 1.2 pmol/l.
Gynecological Endocrinology | 2017
Anne-Sofie Korsholm; Helene Westring Hvidman; J.G. Bentzen; Anders Nyboe Andersen; Kathrine Birch Petersen
Abstract The aim of this cross-sectional study was to investigate side differences in antral follicle count (AFC) and ovarian volume in left versus right ovaries in relation to chronological and “biological” age, the latter estimated by anti-Müllerian hormone (AMH) levels. The cohort comprised 1423 women: 1014 fertile and 409 infertile. All were examined by transvaginal sonography and serum AMH. Overall the right ovary contained 8.1% more antral follicles (p = 0.002) and had 10.7% larger volume compared with the left (p < 0.001). In all AMH quartiles, the right ovarian volume was larger than the left (p ≤ 0.003). AFC was significantly higher in the right compared to the left ovary in the three upper AMH quartiles (p ≤ 0.005). The findings were similar when stratified in age quartiles. More than half (54.8%) had polycystic ovarian (PCO) morphology in at least one ovary. Of these women, 46.3% (n = 361) had PCO morphology unilateral – most frequently on the right side (27.6%) compared to the left (18.7%, p < 0.001). The consistent difference in AFC and ovarian volume found in AMH and age quartiles may be explained by presence of a larger pool of primordial follicles in the right ovary established during fetal life.
Human Reproduction | 2016
Helene Westring Hvidman; J.G. Bentzen; L.L. Thuesen; Mette Petri Lauritsen; Julie Lyng Forman; A. Loft; Anja Pinborg; A. Nyboe Andersen
Human Reproduction | 2012
Y.V. Louwers; M. Roest-Schalken; J. Roeters-van Lennep; Eric J.G. Sijbrands; J.S.E. Laven; J.P. de Bruin; S.C. Braam; M. Brandes; J.M.J. Smeenk; W.L.D.M. Nelen; B.W. Mol; C.J.C.M. Hamilton; Z. Yapici Coskun; G. Bozdag; B.O. Yildiz; I. Esinler; H. Yarali; Mette Petri Lauritsen; J.G. Bentzen; Anja Pinborg; Anne Loft; L.L. Thuesen; A. Nyboe Andersen; F. Yarde; M. Voorhuis; B.C.J.M. Fauser; M.J. Eijkemans; F.J. Broekmans; O. Rustamov; P.W. Pemberton