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Maas Jan Heineman

Bio: Maas Jan Heineman is an academic researcher from University of Amsterdam. The author has contributed to research in topics: Pregnancy rate & Embryo transfer. The author has an hindex of 35, co-authored 115 publications receiving 4897 citations. Previous affiliations of Maas Jan Heineman include University Medical Center Groningen.


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Journal ArticleDOI
TL;DR: The most intriguing effects and mechanisms by which sex hormones affect different components of the immune system in humans are focused on.
Abstract: In addition to their effects on sexual differentiation and reproduction, sex hormones appear to influence the immune system. This results in a sexual dimorphism in the immune response in humans: for instance, females produce more vigorous cellular and more vigorous humoral immune reactions, are more resistant to certain infections, and suffer a higher incidence of autoimmune diseases. Disease expression is also affected by the reproductive status of the female. As sex steroids-estrogens, progesterone and testosterone-differ between gender and within different reproductive stages, a lot of research has focussed on the effects of sex hormones on immune responses. Although there is also a vast literature on the effects of sex hormones on immune responses in animals, in this review we will focus on the most intriguing effects and mechanisms by which sex hormones affect different components of the immune system in humans.

954 citations

Journal ArticleDOI
TL;DR: It is concluded that natural cycle IVF is a low-risk, low-cost and patient-friendly procedure, and a randomized controlled trial comparing natural cycleIVF with current standard treatment strategies is warranted.
Abstract: Since the introduction of IVF treatments, natural cycle IVF has been largely replaced by IVF with ovarian stimulation. However, natural cycle IVF has several advantages. It is associated with a close to zero multiple pregnancy rate, and a zero risk of ovarian hyperstimulation syndrome. Per cycle, natural cycle IVF is less time consuming, physically and emotionally less demanding for patients, and cheaper than stimulated IVF, but also less effective. This systematic literature review addresses the issue of effectiveness of natural cycle IVF. Herein, 20 studies describing natural cycle IVF are presented; 12 case series and eight in which a comparison was made between natural cycle IVF and IVF with ovarian stimulation. Good-quality randomized controlled trials and formal cost-effectiveness analyses are lacking. The 20 selected studies comprised a total of 1800 cycles of natural cycle IVF, resulting in 819 embryo transfers (45.5% per cycle) and 129 ongoing pregnancies (7.2% per cycle and 15.8% per embryo transfer). Efficacy of natural cycle IVF is hampered by high cancellation rates because of premature LH rise and premature ovulations. It is concluded that natural cycle IVF is a low-risk, low-cost and patient-friendly procedure. A randomized controlled trial comparing natural cycle IVF with current standard treatment strategies is warranted.

234 citations

Journal ArticleDOI
TL;DR: Dploid-aneuploid mosaicism is by far the most common chromosomal constitution in spare human preimplantation embryos after IVF, which undermines the reliable determination of the ploidy status of a cleavage-stage embryo based on the analysis of a single cell.
Abstract: results: A total of 815 embryos could be classified. Of these, 177 (22%) were diploid, 599 (73%) were mosaic, of which 480 (59% of the total number of embryos) were diploid -aneuploid mosaic and 119 (14% of the total number of embryos) were aneuploid mosaic, and 39 (5%) contained other numerical chromosomal abnormalities. The distribution of the embryos over these categories was associated with the developmental stage of the embryos, the method used for analysis and the number of chromosomes analysed. conclusions: Diploid -aneuploid mosaicism is by far the most common chromosomal constitution in spare human preimplantation embryos after IVF. This undermines the reliable determination of the ploidy status of a cleavage-stage embryo based on the analysis of a single cell. Future research should determine the origin and developmental potential of mosaic embryos.

229 citations

Journal ArticleDOI
TL;DR: The present review provides an update of current knowledge on the subject of the so-called 'immunological paradox of pregnancy', when the mother must accept a semi-allogeneic fetus.
Abstract: Immune responses play an important role in various reproductive processes, including ovulation, menstruation and parturition. Clearly, during pregnancy, when the mother must accept a semi-allogeneic fetus, immune responses also play a very important role. This was first recognized by Medawar in 1953, when the concept of the fetal allograft was presented in order to explain the immunological relationship between mother and fetus. Since then, the immunology of pregnancy has been the leading subject within reproductive immunology research. Yet, the question of why the semi-allogeneic fetus is not rejected by the mother remains unresolved. The present review provides an update of current knowledge on the subject of the so-called 'immunological paradox of pregnancy'.

227 citations

Journal ArticleDOI
TL;DR: Whether, for couples with unexplained subfertility, IUI improves the live birth rate compared with timed intercourse (TI), or expectant management, both with and without ovarian hyperstimulation (OH), is investigated.
Abstract: BACKGROUND: Intra-uterine insemination (IUI) is a widely-used fertility treatment for couples with unexplained subfertility. Although IUI is less invasive and less expensive than in vitro fertilisation (IVF), the safety of IUI in combination with ovarian hyperstimulation (OH) is debated. The main concern about IUI treatment with OH is the increase in multiple pregnancy rates. OBJECTIVES: To determine whether, for couples with unexplained subfertility, the live birth rate is improved following IUI treatment with or without OH compared to timed intercourse (TI) or expectant management with or without OH, or following IUI treatment with OH compared to IUI in a natural cycle. SEARCH METHODS: We searched the Cochrane Gynaecology and Fertility (CGF) Group trials register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL and two trials registers up to 17 October 2019, together with reference checking and contact with study authors for missing or unpublished data. SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing IUI with TI or expectant management, both in stimulated or natural cycles, or IUI in stimulated cycles with IUI in natural cycles in couples with unexplained subfertility. DATA COLLECTION AND ANALYSIS: Two review authors independently performed study selection, quality assessment and data extraction. Primary review outcomes were live birth rate and multiple pregnancy rate. MAIN RESULTS: We include 15 trials with 2068 women. The evidence was of very low to moderate quality. The main limitation was very serious imprecision. IUI in a natural cycle versus timed intercourse or expectant management in a natural cycle It is uncertain whether treatment with IUI in a natural cycle improves live birth rate compared to treatment with expectant management in a natural cycle (odds ratio (OR) 1.60, 95% confidence interval (CI) 0.92 to 2.78; 1 RCT, 334 women; low-quality evidence). If we assume the chance of a live birth with expectant management in a natural cycle to be 16%, that of IUI in a natural cycle would be between 15% and 34%. It is uncertain whether treatment with IUI in a natural cycle reduces multiple pregnancy rates compared to control (OR 0.50, 95% CI 0.04 to 5.53; 1 RCT, 334 women; low-quality evidence). IUI in a stimulated cycle versus timed intercourse or expectant management in a stimulated cycle It is uncertain whether treatment with IUI in a stimulated cycle improves live birth rates compared to treatment with TI in a stimulated cycle (OR 1.59, 95% CI 0.88 to 2.88; 2 RCTs, 208 women; I2 = 72%; low-quality evidence). If we assume the chance of achieving a live birth with TI in a stimulated cycle was 26%, the chance with IUI in a stimulated cycle would be between 23% and 50%. It is uncertain whether treatment with IUI in a stimulated cycle reduces multiple pregnancy rates compared to control (OR 1.46, 95% CI 0.55 to 3.87; 4 RCTs, 316 women; I2 = 0%; low-quality evidence). IUI in a stimulated cycle versus timed intercourse or expectant management in a natural cycle In couples with a low prediction score of natural conception, treatment with IUI combined with clomiphene citrate or letrozole probably results in a higher live birth rate compared to treatment with expectant management in a natural cycle (OR 4.48, 95% CI 2.00 to 10.01; 1 RCT; 201 women; moderate-quality evidence). If we assume the chance of a live birth with expectant management in a natural cycle was 9%, the chance of a live birth with IUI in a stimulated cycle would be between 17% and 50%. It is uncertain whether treatment with IUI in a stimulated cycle results in a lower multiple pregnancy rate compared to control (OR 3.01, 95% CI 0.47 to 19.28; 2 RCTs, 454 women; I2 = 0%; low-quality evidence). IUI in a natural cycle versus timed intercourse or expectant management in a stimulated cycle Treatment with IUI in a natural cycle probably results in a higher cumulative live birth rate compared to treatment with expectant management in a stimulated cycle (OR 1.95, 95% CI 1.10 to 3.44; 1 RCT, 342 women: moderate-quality evidence). If we assume the chance of a live birth with expectant management in a stimulated cycle was 13%, the chance of a live birth with IUI in a natural cycle would be between 14% and 34%. It is uncertain whether treatment with IUI in a natural cycle results in a lower multiple pregnancy rate compared to control (OR 1.05, 95% CI 0.07 to 16.90; 1 RCT, 342 women; low-quality evidence). IUI in a stimulated cycle versus IUI in a natural cycle Treatment with IUI in a stimulated cycle may result in a higher cumulative live birth rate compared to treatment with IUI in a natural cycle (OR 2.07, 95% CI 1.22 to 3.50; 4 RCTs, 396 women; I2 = 0%; low-quality evidence). If we assume the chance of a live birth with IUI in a natural cycle was 14%, the chance of a live birth with IUI in a stimulated cycle would be between 17% and 36%. It is uncertain whether treatment with IUI in a stimulated cycle results in a higher multiple pregnancy rate compared to control (OR 3.00, 95% CI 0.11 to 78.27; 2 RCTs, 65 women; low-quality evidence). AUTHORS' CONCLUSIONS: Due to insufficient data, it is uncertain whether treatment with IUI with or without OH compared to timed intercourse or expectant management with or without OH improves cumulative live birth rates with acceptable multiple pregnancy rates in couples with unexplained subfertility. However, treatment with IUI with OH probably results in a higher cumulative live birth rate compared to expectant management without OH in couples with a low prediction score of natural conception. Similarly, treatment with IUI in a natural cycle probably results in a higher cumulative live birth rate compared to treatment with timed intercourse with OH. Treatment with IUI in a stimulated cycle may result in a higher cumulative live birth rate compared to treatment with IUI in a natural cycle.

194 citations


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01 Jan 2016
TL;DR: The using multivariate statistics is universally compatible with any devices to read, allowing you to get the most less latency time to download any of the authors' books like this one.
Abstract: Thank you for downloading using multivariate statistics. As you may know, people have look hundreds times for their favorite novels like this using multivariate statistics, but end up in infectious downloads. Rather than reading a good book with a cup of tea in the afternoon, instead they juggled with some harmful bugs inside their laptop. using multivariate statistics is available in our digital library an online access to it is set as public so you can download it instantly. Our books collection saves in multiple locations, allowing you to get the most less latency time to download any of our books like this one. Merely said, the using multivariate statistics is universally compatible with any devices to read.

14,604 citations

Posted Content
TL;DR: Deming's theory of management based on the 14 Points for Management is described in Out of the Crisis, originally published in 1982 as mentioned in this paper, where he explains the principles of management transformation and how to apply them.
Abstract: According to W. Edwards Deming, American companies require nothing less than a transformation of management style and of governmental relations with industry. In Out of the Crisis, originally published in 1982, Deming offers a theory of management based on his famous 14 Points for Management. Management's failure to plan for the future, he claims, brings about loss of market, which brings about loss of jobs. Management must be judged not only by the quarterly dividend, but by innovative plans to stay in business, protect investment, ensure future dividends, and provide more jobs through improved product and service. In simple, direct language, he explains the principles of management transformation and how to apply them.

9,241 citations

Journal Article

4,293 citations

Journal ArticleDOI
TL;DR: It is emphasized that sex is a biological variable that should be considered in immunological studies and contribute to variations in the incidence of autoimmune diseases and malignancies, susceptibility to infectious diseases and responses to vaccines in males and females.
Abstract: Males and females differ in their immunological responses to foreign and self-antigens and show distinctions in innate and adaptive immune responses. Certain immunological sex differences are present throughout life, whereas others are only apparent after puberty and before reproductive senescence, suggesting that both genes and hormones are involved. Furthermore, early environmental exposures influence the microbiome and have sex-dependent effects on immune function. Importantly, these sex-based immunological differences contribute to variations in the incidence of autoimmune diseases and malignancies, susceptibility to infectious diseases and responses to vaccines in males and females. Here, we discuss these differences and emphasize that sex is a biological variable that should be considered in immunological studies.

3,214 citations

Journal ArticleDOI
TL;DR: Polanyi is at pains to expunge what he believes to be the false notion contained in the contemporary view of science which treats it as an object and basically impersonal discipline.
Abstract: The Study of Man. By Michael Polanyi. Price, $1.75. Pp. 102. University of Chicago Press, 5750 Ellis Ave., Chicago 37, 1959. One subtitle to Polanyi's challenging and fascinating book might be The Evolution and Natural History of Error , for Polanyi is at pains to expunge what he believes to be the false notion contained in the contemporary view of science which treats it as an object and basically impersonal discipline. According to Polanyi not only is this a radical and important error, but it is harmful to the objectives of science itself. Another subtitle could be Farewell to Detachment , for in place of cold objectivity he develops the idea that science is necessarily intensely personal. It is a human endeavor and human point of view which cannot be divorced from nor uprooted out of the human matrix from which it arises and in which it works. For a good while

2,248 citations