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Log-linear analysis is a practical tool for examining relationships, successfully applied in many fields of science. This paper discusses the topic of estimation of the chance of getting pregnant in couples that underwent ART insemination. The authors focus on finding significant interactions between variables, on the basis of which statistical models are built. With the use of results of log-linear analysis, a model predicting the chances of achieving a clinical pregnancy that contained interactions was successfully built. Moreover, it was more complete than the model obtained with the use of logistic regression alone.

Infertility is a huge problem nowadays, not only from the medical but also from the social point of view. A key step to improve treatment outcomes is the possibility of effective prediction of treatment result. In a situation when a phenomenon with more than 2 states needs to be explained, e.g. pregnancy, miscarriage, non-pregnancy, the use of multinomial logistic regression is a good solution. The aim of this paper is to select those features that have a significant impact on achieving clinical pregnancy as well as those that determine the occurrence of spontaneous miscarriage (non-pregnancy was set as the reference category). Two multi-factor models were obtained, used in predicting infertility treatment outcomes. One of the models enabled to conclude that the number of follicles and the percentage of retrieved mature oocytes have a significant impact when prediction of treatment outcome is made on the basis of information about oocytes. The other model, built on the basis of information about embryos, showed the significance of the number of fertilized oocytes, the percentage of at least 7-cell embryos on day 3, the percentage of blasts on day 5, and the day of transfer.

Maternal effect genes (MEGs) are expressed in oocytes and embryos and play an important role in activation of the embryonic genome. An abnormality in the expression of these genes may lead to arrest of embryonic cleavage or to altered transcription of factors responsible for further embryonic development. In vitro-produced porcine embryos have a lower developmental potential than embryos produced in vivo. We hypothesized that in vitro embryo culture conditions have an effect on the expression of MEGs at various developmental stages, which may affect their developmental potential. Here, using real-time polymerase chain reaction, we examined mRNA profiles of the MEGs, zygote arrest 1 (ZAR-1), nucleoplasmin 2 (NPM2), and developmentally associated pluripotency protein 3 (DPPA3), in porcine oocytes and embryos produced in vitro and in vivo. Further, we evaluated the effect of the combined addition of EGF, interleukin 1β, and leukemia inhibitory factor to the porcine in vitro embryo production system on mRNA profiles of selected MEGs. Finally, we studied localization of the MEG protein products in in vitro-obtained oocytes and embryos using confocal microscopy. We found that the ZAR-1 mRNA profile differed throughout in vitro and in vivo embryo development. In the embryos produced in vitro, the decrease in ZAR-1 mRNA levels was observed at the 2-cell stage, whereas in in vivo embryos, ZAR-1 mRNA levels declined significantly starting at the 4-cell stage (P 0.05). In vitro culture conditions affected transiently also DPPA3 mRNA levels at the 4-cell stage (P 0.05). There was no difference in the NPM2 mRNA profile during in vitro and in vivo embryo development. The ZAR-1 and DPPA3 proteins were localized in the cytoplasm of the oocytes and embryos, whereas the NPM2 protein was found both in the cytoplasm and in the nucleus. All proteins were expressed until blastocyst stage. The addition of EGF and cytokines to the culture medium decreased DPPA3 mRNA levels in 8-cell embryos (P 0.05). This study indicated that IVC conditions affect ZAR-1 mRNA levels before the 4-cell stage, which may disturb the activation of the embryonic genome in pigs. The expression of the proteins after the 4-cell to 8-cell transition indicates that these factors play a role beyond activation of the embryonic genome. Supplementation of the culture media with EGF and cytokines affects DPPA3 mRNA levels after maternal to embryonic transition.

There are high hopes for using the artificial neural networks (ANN) technique to predict results of infertility treatment using the in vitro fertilization (IVF) method. Some reports show superiority of the ANN approach over conventional methods. However, fully satisfactory results have not yet been achieved. Hence, there is a need to continue searching for new data describing the treatment process, as well as for new methods of extracting information from these data. There are also some reports that the use of principal component analysis (PCA) before the process of training the neural network can further improve the efficiency of generated models. The aim of the study herein presented was to verify the thesis that the use of PCA increases the effectiveness of the prediction by ANN for the analysis of results of IVF treatment. Results for the PCA-ANN approach proved to be slightly better than the ANN approach, however the obtained differences were not statistically significant.

Infertility is currently a common problem with causes that are often unexplained, which complicates treatment. In many cases, the use of ART methods provides the only possibility of getting pregnant. Analysis of this type of data is very complex. More and more often, data mining methods or artificial intelligence techniques are appropriate for solving such problems. In this study, classification trees were used for analysis. This resulted in obtaining a group of patients characterized most likely to get pregnant while using in vitro fertilization.

One of the most effective methods of infertility treatment is in vitro fertilization (IVF). Effectiveness of the treatment, as well as classification of the data obtained from it, is still an ongoing issue. Classifiers obtained so far are powerful, but even the best ones do not exhibit equal quality concerning possible treatment outcome predictions. Usually, lack of pregnancy is predicted far too often. This creates a constant need for further exploration of this issue. Careful use of different classification methods can, however, help to achieve that goal.

Many factors play an important role in prediction of infertility treatment outcome (for example, female age and quality of oocytes or embryos are the most important prognostic factors concerning positive IVF outcome). The purpose of this study was to identify a set of variables that could fulfill criteria for prediction of pregnancy in IVF patients through the application of data mining – using the discriminant analysis method. The principle of this method is to establish a set of rules that allows one to place multi-dimensional objects into one of two analyzed groups (pregnant or not pregnant). Six hundred and ten IVF cycles were included in the analysis and the following variables were taken into consideration: female age, number and quality of retrieved oocytes, number and quality of embryos, number of transferred embryos, and outcome of treatment. Discriminant analysis allowed for the creation of a model with a 51.22% correctness of prediction to achieve pregnancy during IVF treatment and with 74.07% correctly predicted failure of pregnancy. Therefore, the created model is more suitable for the prediction of a negative outcome (lack of pregnancy) during IVF treatment and offers an option for adjustments to be made during infertility treatment.

Principal Component Analysis is one of the data mining methods that can be used to analyze multidimensional datasets. The main objective of this method is a reduction of the number of studied variables with the mainte- nance of as much information as possible, uncovering the structure of the data, its visualization as well as classification of the objects within the space defined by the newly created components. PCA is very often used as a preliminary step in data preparation through the creation of independent components for further analysis. We used the PCA method as a first step in analyzing data from IVF (in vitro fertilization). The next step and main purpose of the analysis was to create models that predict pregnancy. Therefore, 805 different types of IVF cy- cles were analyzed and pregnancy was correctly classified in 61-80% of cases for different analyzed groups in obtained models.

The purpose of our study was to assess the effect of vitrification with or without the presence of calcium in the vitrification solution on the: 1) diameter of oocytes and thickness of the zona pellucida, 2) zona pellucida hardening, 3) expression of mRNA follistatin (FST) and cathepsin B (CTSB) in oocytes and 4) developmental competence of embryos derived from in vitro matured and vitrified oocytes. The results of our study demonstrate, that vitrification did not alter thickness of the zona pellucida and diameter of the oocytes, however it triggered hardening of the zona pellucida. The presence of calcium in the vitrification solutions intensified hardening of zona in immature and mature oocytes (P 0.04, P 0.001, respectively) and provoked increased mRNA FST expression in oocytes matured in vitro compared to immature oocytes (P 0.01) and those vitrified without calcium (P 0.004). CTSB mRNA expression was increased in immature oocytes and oocytes vitrified with calcium compare to mature oocytes (P 0.02). The developmental potential of vitrified oocytes was impaired compared to non-vitrified oocytes, being more evident in oocytes vitrified with calcium. In summary, vitrification did not change the oocyte diameter and thickness of the zona pellucida and expression of FST and CTSB mRNA. It diminished developmental potential of the vitrified oocytes. The presence of calcium in the vitrification solutions increased hardening of zona pellucida as well as affected the level of FST and CTSB mRNA in oocytes and developmental potential of these oocytes.

SummaryMaternal effect genes (MEG) play a crucial role in early embryogenesis. In vitro culture conditions may affect MEG expression in porcine oocytes and embryos. We investigated whether in vitro culture medium supplementation with epidermal growth factor (EGF), IL-1β or LIF (leukemia inhibitory factor) affects the mRNA level of ZAR-1 (zygote arrest 1), NPM2 (nucleoplasmin 2) and DPPA3 (developmental associated protein 3) in porcine MII oocytes and embryos. Cumulus–oocyte complexes (COCs) were matured in NCSU-37 medium (control) or in NCSU-37 with EGF 10 ng/ml, IL-1β 10 ng/ml or LIF 50 ng/ml. After maturation for 44–46 h, MII oocytes were preserved for the analysis of MEG mRNA levels (experiment 1). In experiment 2, COCs were fertilized, and the presumptive zygotes were cultured in the same groups. Then, 2-, 4-, 8-cell embryos, morulae and blastocysts were collected for the analysis of MEG mRNA levels. LIF addition to the maturation medium increased MII oocyte numbers (P < 0.05), while EGF and IL-1β did not affect oocyte maturation. Medium supplementation with EGF resulted in lower DPPA3 mRNA levels in MII oocytes and in 2- and 4-cell embryos versus control embryos (P < 0.05). LIF treatment increased DPPA3 mRNA levels in morulae and blastocysts (P < 0.05). Culture with EGF and IL-1β decreased ZAR-1 and NPM2 mRNA levels in 2-cell embryos (P < 0.05). The inclusion of EGF or IL-1β in the porcine in vitro production system influences ZAR-1, NPM2 and DPPA3 mRNA in MII oocytes and embryos but not beyond the 4-cell stage. LIF stimulates oocyte maturation and affects DPPA3 mRNA in porcine morulae and blastocysts in vitro.

Intrauterine insemination (IUI) is one of many treatments provided to infertility patients. Many factors such as, but not limited to, quality of semen, the age of a woman, and reproductive hormone levels contribute to infertility. Therefore, the aim of our study is to establish a statistical probability concerning the prediction of which groups of patients have a very good or poor prognosis for pregnancy after IUI insemination. For that purpose, we compare the results of two analyses: Cluster Analysis and Kohonen Neural Networks. The k-means algorithm from the clustering methods was the best to use for selecting patients with a good prognosis but the Kohonen Neural Networks was better for selecting groups of patients with the lowest chances for pregnancy.

Infertility is recognized as a major problem of modern society. Assisted Reproductive Technology (ART) is the one of many available treatment options to cure infertility. However, the efficiency of the ART treatment is still inadequate. Therefore, the procedure’s quality is constantly improving and there is a need to determine statistical predictors as well as contributing factors to the successful treatment. There is a concern over the application of adequate statistical analysis to clinical data: should classic statistical methods be used or would it be more appropriate to apply advanced data mining technologies? By comparing two statistical models, Multivariable Logistic Regression analysis and Artificial Neural Network it has been demonstrated that Multivariable Logistic Regression analysis is more suitable for theoretical interest but the Artificial Neural Network method is more useful in clinical prediction.

The purpose of this retrospective study was to establish a prognosis for implantation, pregnancy and live birth rates in stimulated IVF cycles after transferring embryos derived from: 1/ retrieved immature oocytes that matured overnight in vitro (late mature group: LM); 2/ retrieved immature oocytes that matured overnight in vitro and were added to the embryos derived from retrieved mature oocytes (mixed embryos group: MX); and 3/ retrieved mature oocytes (mature group: M). The obtained implantation, clinical pregnancy and live birth rates for the LM group were: 5.6%, 11.4%, 11.4%; for the MX group were: 4.2%, 14.6%, 11.6%; and for the M group were: 14.6%, 45.2% and 33.3%, respectively. These measurements were significantly lower p0.05 for the LM and MX groups in comparison to the M group. The number of oocytes retrieved and the number of embryos transferred were the lowest (p0.001-0.05) for the LM group. It is concluded, that the retrieved immature oocytes are able to mature during overnight culture in vitro, be fertilized and provide developmentally competent embryos with the prognosis of 11% for the successful delivery.