Loss Factor Research Articles

Risk factors and evolution of weight loss in Parkinson’s disease: a 9-year population-based study

Introduction:Weight loss is considered a common complication of Parkinson`s disease (PD), but there are few prospective longitudinal studies on weight loss in patients followed from time of PD diagnosis. We sought to determine the frequency, evolution and risk factors of weight loss in a representative incident PD cohort. Methods: In this prospective population-based observational study, we followed 180 newly-diagnosed, initially drug-naïve PD patients and 161 controls with repetitive weight examinations over 9 years. We used Cox regression models with adjustment for potential confounders to identify independent risk factors of clinically significant (>10%) weight loss. Results: Mean % weight change during follow-up was -3.9 (±11.2) in patients and -1.4 (±8.1) in controls (p=0.016). Clinically significant weight loss was observed in 26.7% of patients and 10.6% of controls (RR 2.53; 95% CI 1.52-4.21; p<0.001). Age was the only independent baseline risk factor for weight loss (HR 1.06 per year; 95% CI 1.03-1.10; p<0.001). Additional time-dependent risk factors were presence of olfactory impairment (HR 2.42; 95% CI 1.14-5.15; p=0.021), presence of dyskinesias (HR 3.14; 95% CI 1.58-6.23; p=0.001), and cognitive impairment (HR per MMSE unit 0.90; 95% CI 0.82-0.99; p=0.036). Dopamine agonist use reduced the risk of weight loss during follow-up (HR 0.44; 95% CI 0.24-0.82; p=0.007) Conclusion: The risk of weight loss is more than doubled in the general PD population and associated with both disease-related features and drug-related complications. This suggests a multifactorial nature of weight loss in PD, which is important to consider in research and clinical practice.

Projected evolution of the Qiyi Glacier in the Qilian Mountains using the PyGEM with the calibration of glaciological mass balance

Owing to glacial retreat and associated future runoff variations, major concerns have been raised over the sustainability of water resources in the Qilian Mountains. Based on the Python Glacier Evolution Model, we present projections of the Qiyi glacier for shared socioeconomic pathways (SSPs) calibrated with the glaciological mass balance. The results indicate the air temperature as the dominant factor in the continuous mass loss of the Qiyi Glacier in the future. Glacier area and volume are projected to decline to 0.16 ± 0.11 km2 (6.4% ± 4.4%, relative to 2015) and 0.0023 ± 0.0006 km³ (2.1% ± 1.5%, relative to 2015), respectively, by 2100, for SSP1-2.6. For SSP5-8.5, the glacier will disappear by 2088. The mass loss of the Qiyi Glacier will accelerate before 2050 for all SSPs but will decelerate after 2050 for SSP1-2.6 and SSP2-4.5. The peak water of glacier runoff will occur between 2034 and 2045, with the duration of high water from 7 to 18 years. Thereafter, the runoff will rapidly decline till 2070–2080 and remain low afterward. Compared with the existing projections, the present projections indicate that the Qiyi Glacier will experience more drastic shrinkage and ice loss in the coming decades. Finally, the glacier runoff is expected to reach its peak water earlier with a shorter duration of high water.

The Influence of Personal Listening Devices on Hearing in Egyptian University Students: A Cross-Sectional Study

Background: Improper use of personal listening devices (PLDs) is associated with an increased risk of hearing loss. The purpose is to investigate the use of PLDs among university students and their impact on hearing. Methodology: A study involved 310 University students, surveyed on their PLDs habits. They shared their daily PLD use, volume level, and duration of use. Participants also discussed PLD-related hearing issues and other risk factors for hearing loss. Screening used the Five-minute hearing test (FMHT) and the “Hear WHO” app. Positive cases in both tests received diagnostic pure-tone audiometry (PTA). Results: About 70% used in-earpiece PLDs for studying, 53% used them for over 5 years. Also 83% used PLDs for over 60 mins daily, and 72% used them above volume level 6. Most (74%) were low-risk users. 10.6% tested positive for hearing loss in both screenings, with 1.6% confirmed by PTA. A shift in the 4 kHz average hearing threshold was noted. Tinnitus was reported by 49%, and ear pain by 42% of students. Higher risk PLD use predicted tinnitus, ear pain and excessive ear wax in multivariable analysis. Conclusions: Students' high-volume PLD use is linked to auditory problems like tinnitus and ear pain. Regular hearing screenings are recommended.

Assessment of the productivity loss due to leading maternal ill-health conditions: a follow-up study of a prospective pregnancy cohort in rural Sri Lanka.

This study aimed to assess the productivity loss and cost due to maternal ill-health conditions and its associated factors throughout pregnancy in rural Sri Lanka. A follow-up study of women registered in the Rajarata Pregnancy Cohort (RaPCo). Anuradhapura district, Sri Lanka. 1573 pregnant women who were followed up from pregnancy identification to termination. The primary outcome measures of this study are productivity loss due to maternal ill-health conditions expressed by days/month and productivity cost due to maternal ill-health conditions expressed in monetary terms (US$)/month. Data were collected monthly, and all pregnant women were asked to report the leading cause of maternal ill-health condition and the associated loss due to absenteeism and presenteeism. During the pregnancy follow-up, 3595 (81.5%) months had at least one episode of maternal ill-health condition. Of these, only 1729 (48.1%) episodes sought medical care. Assistance for lost routine work was reported in 1281 (35.6%) episodes. The absenteeism, presenteeism and gross and net productivity loss per month were 3.6, 4.5, 8.1 and 5.5 days/month, respectively. The corresponding productivity cost was US$15.26/month. Nausea and vomiting (NVP) reported the highest prevalence (n=1599, 44.5%) until the second month of the third trimester, presenteeism (5.5 days/month) and gross productivity loss (9.5 days/month). Pregnant women with vaginal bleeding reported the highest absenteeism (6.2 days/month) and net productivity loss (6.8 days/month). Pregnant women diagnosed with anaemia reported the highest productivity cost (US$26.98/month). Monthly household expenditure, poverty and receiving assistance were the associated factors of productivity loss (p<0.05). Maternal ill-health conditions during pregnancy lead to productivity loss in rural Sri Lanka. NVP, vaginal bleeding and anaemia are the leading causes of productivity loss. Hence, controlling and preventing the leading causes are the recommended priorities.

Analysis of Characteristics and Prognostic Factors of Full-Frequency Idiopathic Sudden Sensorineural Hearing Loss with Hyperlipidemia.

To explore the relationship between hyperlipidemia and full-frequency idiopathic sudden sensorineural hearing loss (FFHL). A total of 145 FFHL patients admitted from September 2021 to May 2024 were analyzed. Eighty-five patients with hyperlipidemia and 60 patients with normal serum lipids statistically analyze the patient's gender, age, onset time, accompanying symptoms, and serum lipids. Measure the pure tone hearing threshold before and after treatment, and calculate the average increase in hearing threshold. Compare the correlation between various factors and prognosis. The hyperlipidemia group had a higher proportion of males (P=0.043) and vertigo (P=0.044) compared to the control group, while other information between the two groups lacked statistical significance. Effective patients (n=44) in the hyperlipidemia group showed significant differences in vertigo (P=0.020), age (P=0.032), and onset (P=0.030) compared to ineffective patients (n=41). Analysis showed that these were independent correlated factors affecting prognosis. Other indicators, including serum lipids, have no significance in predicting the prognosis of patients with hyperlipidemia and complete frequency decline in hearing loss. Patients with hyperlipidemia have higher rates of males and vertigo. The age, onset, and vertigo of patients with hyperlipidemia are related to prognosis, while various lipid indicators are not related to the prognosis of sudden hearing loss.

Impaired stemness in aging periodontal ligament stem cells is mediated by the progerin/endoplasmic reticulum stress/p53 axis

IntroductionDecreased periodontal ligament stem cells (PDLSCs) stemness is a key factor in age-related alveolar bone loss. Endoplasmic reticulum (ER) stress is closely related to age-related diseases and the mesenchymal stem cell (MSC) stemness. However, the role of ER stress in regulating the stemness of senescent PDLSCs and its potential mechanism remain unclear. ObjectivesTo investigate the detailed effect and mechanism of ER stress on impaired stemness in old periodontal ligament stem cells (OPDLSCs). MethodsThe level of ER stress of Young PDLSCs (YPDLSCs) and OPDLSCs were detected, and ER stress was regulated to observe its effect on PDLSCs stemness. The expression levels of ER stress sensors (protein kinase R-like ER kinase (PERK), activating transcription factor 6 (ATF6), inositol requiring enzyme 1 (IRE1)) were upregulated in YPDLSCs and downregulated in OPDLSCs by transfection experiments to verify the detailed unfolded protein response (UPR) pathway. Mechanismly, the regulatory effect of UPR pathway on p53/p21 pathway was explored. Further study was performed to investigated the important role of progerin accumulation during aging process on ER stress, UPR and p53/p21 pathway. ResultsDecreased stemness and ER stress activation were found in OPDLSCs. ER stress activation resulted in decreased stemness of YPDLSCs, while ER stress inhibition rescued compromised stemness of OPDLSCs. Mechanismly, ATF6 pathway regulated the OPDLSC stemness via the p53/p21 signaling as confirmed by transfection assay. Further study showed that progerin was accumulated in PDLSCs and progerin overexpression could resulted in ER stress activation, activating the ATF6/p53/p21 axis, leading to decreased stemness of aging PDLSCs. ConclusionsProgerin accumulation during the aging process can lead to ER stress activation, which can suppress OPDLSC stemness via the ATF6/p53/p21 axis.

Risk factors of bone loss after Prestige-LP cervical disc arthroplasty.

Cervical disc arthroplasty (CDA) is widely employed for patients diagnosed with cervical degenerative disc disease (CDDD). Postoperative bone loss (BL) represents a radiological alteration that is a relatively novel consideration in the realm of CDA. This study endeavors to examine the risk factors associated with BL following CDA, aiming to elucidate the underlying mechanisms and the impact of BL on surgical outcomes. A retrospective study was undertaken, encompassing consecutive patients subjected to one-level CDA, two-level CDA, or two-level hybrid surgery (HS) for the treatment of CDDD at our institution. Patient demographic and perioperative data were systematically recorded. Radiological images obtained preoperatively, at 1-week post-operation, and during the last follow-up were collected and evaluated, following with statistical analyses. A total of 295 patients and 351 arthroplasty segments were involved in this study. Univariate logistic regressions indicated that age ≥ 45years and two-level HS was associated with lower risk of BL; and a greater ΔDA (change of disc angle before and after surgery) was correlated with an increased risk of BL. Multivariate logistic regression determined that two-level HS and greater ΔDA were independent preventative and risk factors for BL, respectively. Further analysis revealed that severe BL significantly elevated the risk of implant subsidence compared to non-BL and mild BL. This study posited bone remodeling and micromotion as potential underlying mechanisms of BL. Subsequent research endeavors should delve into the divergent mechanisms and progression observed between lower- and higher-grade BL, aiming to prevent potential adverse outcomes associated with severe BL.

Risk Factors for Death-Censored Graft Loss and Death in Kidney Transplant Recipients with Delayed Graft Function

Risk Factors for Death-Censored Graft Loss and Death in Kidney Transplant Recipients with Delayed Graft Function

The effects of land cover transition and its patch mosaics on soil erosion using geospatial technology in South Wollo, Ethiopia

Soil erosion has been a significant threat to agricultural productivity, dam sustainability, and ecosystem services in the highlands of Ethiopia. Despite some watershed-specific research on this problem, the spatiotemporal distribution of soil erosion risks is still rarely assessed in South Wollo. This study aims to monitor land cover changes, analyze landscape mosaics, and estimate soil loss in South Wollo from 1990 to 2020. The Revised Universal Soil Loss Equation (RUSLE) was utilized to estimate soil loss. Key informant interviews and field observations were conducted to gain further insights into land cover change and soil erosion. The results showed that agricultural land use was dominant, covering 50.75 % of the study area in 1990 and it continued to expand at an annual rate of 1.73 %, primarily on shrubland and grassland. The landscape structure was more heterogeneous in the north compared to the central and southern areas. In 1990, the mean soil loss was 21.13 t ha-1yr−1, totaling 41.53 million tons. By 2020, These figures had increased to 28.97 t ha-1yr−1 and 49.86 million tons, respectively. Areas experiencing very severe soil erosion (>50 t ha-1yr−1) expanded from 10.81 % (1990) to 13.57 % (2020). The magnitude of soil loss also differed among land cover types, with the highest rates observed in bare land (>85 t ha-1yr−1), followed by agricultural land (>30 t ha-1yr−1). Soil loss factors and landscape metrics exhibited a significant correlation with soil loss, though the strength and direction of these interactions varied. Land cover change and its associated soil erosion were primarily exacerbated by policy factors, including tenure insecurity and disregard for farmers’ indigenous conservation knowledge. This study offers valuable insights into the trends of land cover transitions, landscape structure, and soil loss. It will help guide sustainable land management, aimed at increasing green legacy and reducing soil loss.

Phase transition suppression, thermal and electrical properties of (YNb)0.2Zr0.6P2O7

ZrP2O7 is a promising material with excellent thermal and electrical properties. However, when temperature approaches to 563 K, it undergoes a structural phase transition, which will cause large thermal stresses. When Zr is substituted by Y and Nb, a new material of (YNb)0.2Zr0.6P2O7, was successfully prepared and the phase transition of material was effectively inhibited. This new material adopts a cubic structure similar to ZrP2O7, and exhibits medium thermal expansion (α = 7.1×10-6 K-1) in the measured range of 200-1073 K. The values of thermal conductivity from RT to 973 K are between 0.4474 W·m-1·K-1 and 0.8526 W·m-1·K-1, which can be comparable to the values of traditional thermal insulation materials. The dielectric constant and dielectric loss factor at the frequencies above 1 MHz are stable and low. The electrical conductivity of the material indicates that it is electronically insulating at RT-573 K.

Physical Exercise as a Modulator of the Levels of Leptin/Adiponectin Relation and Inflammation in Chronic Kidney Disease

Chronic kidney disease (CKD) is an important factor of loss of quality of life and high rates of morbidity and mortality, where cardiovascular diseases are the main responsible for this poorer prognosis. It is verified that CKD is associated with high inflammatory levels in the body, or that it seems to contribute to these cardiovascular events. Thus, CKD is characterized by a high inflammatory profile, as well as possibly a large imbalance in adipokines due to changes in body composition. Thus, adiponectin and leptin emerge as possible inflammatory modulators, although their popular effects are not completely elucidated. On the other hand, it is proven that physical exercise can be a great tool in the treatment of CKD and in the modulation of biomarkers, stimulating in an anti-inflammatory way and promoting an adjustment in the main causes of morbidity and mortality in this population. Thus, this review seeks to elucidate the role of exercise as a modulator of inflammation and the leptin/adiponectin relationship in order to contribute to the better quality of life of this population, in addition to demonstrating the important role that exercise can exert in modulation of these biomarkers, aiming to minimize the cardiovascular effects that these biomarkers exert on this population.

REVIEW OF PARAMETERS INFLUENCING WIRELESS ENERGY TRANSMISSION BY MAGNETIC INDUCTION

In this review article, we present a detailed study and discussion of wireless energy transfer systems based on studies in the literature, with the help of Python programming software. Starting from the basic element of wireless transmission by magnetic induction, i.e. the coil, through a magnetostatic study we have highlighted the impact of geometry, coil misalignment and coil loss factors on these transmission systems. We have also shown that parameters such as coupling coefficient and frequency can improve transmitted power and efficiency. A summary of the latest research in this field will also be given.

Rare earth samarium substituted barium-calcium hexaferrites: Insight into structure, dielectric and magnetic aspects

This study presents the synthesis of samarium-substituted Ba-Ca hexaferrites (Ba0.5Ca0.5Fe12-xSmxO19) utilizing the sol–gel method. X-ray diffraction (XRD) analysis is performed to evaluate the structure of fabricated materials. The lattice shows an expansion up to a doping concentration of x = 0.12, and minor contraction at x = 0.16. Both X-ray density and bulk density exhibit an upward trend with increasing doping levels, while porosity reduces and dislocation density shows an increase. Scanning electron microscopy (SEM) confirms the homogeneity and uniformity of the doped samples. The dielectric properties displays the interaction of the materials with an external electric field, revealing that the dielectric constant (ε′), dielectric loss (ε″), and dissipation factor progressively increases with samarium concentration. Magnetic characterizations demonstrate a significant enhancement in saturation magnetization and coercivity, attaining peak values of 33.19 emu/g and 1.805 kOe, respectively. Moreover, the anisotropy field (Ha) and anisotropy constant (K) shows an increase with higher doping concentrations confirming the prepared material as an alternative for electric and magnetic industry applications.

Association between Periodontal Disease and Bone Loss among Ambulatory Postmenopausal Women: A Cross-Sectional Study

Background/Objectives: Osteoporosis and periodontal disease (PD) are associated with significant morbidity and mortality especially among post-menopausal women. The attributable causes of mortality include bone fragility, hip fractures, surgical risks, complications associated with immobility/disability, and mental health issues. This cross-sectional study aims to investigate the association between oral health and bone diseases along with the factors that predict this association. Methods: This study included post-menopausal women undergoing routine bone density evaluation. Following informed consent, case histories were collected using an investigator-administered questionnaire. The oral cavity was inspected for the health of the oral structures and periodontium. Bone density data, interpreted by a radiologist, were also collected. Data were analyzed using chi-square and logistic regression tests with the significance level set at 5%. Results: Among 100 eligible participants, mean age and body mass index (BMI) were 68.17 ± 8.33 years and 29.59 ± 6.13 kg/m2, respectively. A total of 23 participants (23.0%) had T2DM, 29 (29.0%) had &lt; 20 natural teeth, and 17 (17.0%) had normal bone mineral density. Except for age (aOR 1.171, p &lt; 0.001), BMI (aOR 0.763, p &lt; 0.001), and past osteoporotic fractures (aOR 21.273, p = 0.021), all other factors were insignificant predictors of bone loss. Conclusions: Although the unadjusted results suggest a relationship between oral health indicators and bone loss, these relationships were not present when other factors were included in an adjusted model. Our findings suggest PD by itself may not be a risk factor for bone loss but that the two conditions may have similar risk factors.

Regulating the interfacial structure in percolating graphite nanoplate/PVDF composites via TiO2 as an interlayer towards meliorative dielectric performances

Polymer nanocomposites combining large dielectric permittivity (ε′) but low loss along with high breakdown strength (Eb) have garnered significant attention in the fields of electronic devices and power systems. To concurrently accomplish these desirable performances in pristine graphite nanoplates (GNP)/poly(vinylidene fluoride, PVDF) composites, the GNP were initially encased by a layer of anatase-type titanium dioxide (TiO2) shell, and then incorporated into PVDF to investigate the effect of TiO2 interlayer on the dielectric properties of the nanocomposites, specifically in relation to the thickness of the TiO2 shell and the nanofiller concentration. The TiO2 shell acts as a barrier layer prohibiting the electronic percolating, thus significantly reducing the dielectric loss and leakage conductivity of the GNP@TiO2/PVDF. Moreover, it not only alleviates the strong dielectric mismatch between GNP and PVDF, which restrains local electric field distortion, but also introduces charge traps, raising the energy barrier height for captured charge detrapping and preventing the growth of electric trees and subsequently promoting the Eb. For example, the PVDF with 20 wt% of GNP@TiO2 exhibited good comprehensive dielectric performances: ε′ of 50.63, loss factor of 0.071 (100 Hz) and Eb of 7.89 kV/mm. Additionally, tailoring the TiO2’s thickness can simultaneously modulate the overall dielectric parameters in the GNP@TiO2/PVDF. Theoretical fitting of experimental data via Havriliak-Negami equation uncovers the underlying polarization mechanism and the interlayer’s impact on charge migration. This work provides an efficient method for developing and producing polymeric nanodielectrics that simultaneously incorporate increased Eb with high ε′ but low loss for potential use in power devices and microelectronic devices.

Long-term changes in bone mineral density and associated risk factors in individuals with spinal cord injury: A retrospective study.

Individuals with spinal cord injury (SCI) experience a notable decrease in bone mass below the level of injury. While studies have primarily focused on the acute phase with a small cohort, this study aimed to provide comprehensive insights into bone loss patterns over time. A total of 427 individuals with SCI who underwent dual-energy X-ray absorptiometry (DXA) testing at the Korea National Rehabilitation Center (2010-2021) were included and analyzed by categorizing the DXA results into 1-year intervals based on postinjury duration. Demographic characteristics (age, sex, body mass index, and alcohol/smoking history) and SCI-related factors (etiology, severity, extent of injury, motor score, and Korean Spinal Cord Independence Measure 3rd edition) were collected and analyzed. Linear mixed models and Bonferroni post hoc tests were performed to assess temporal changes in bone mass and linear regression analysis to assess the associations between possible risk factors and bone loss. DXA results revealed that substantial annual bone loss occurred in the total hip site up to 3 years postinjury and in the femoral neck site up to 2 years postinjury. Old age, women, and low body mass index were significant risk factors for bone loss in the SCI population. Additionally, during the chronic phase, lower Korean Spinal Cord Independence Measure 3rd edition scores were associated with low bone mass. Significant annual bone loss in the hip region persists for up to 3 years postinjury in individuals with SCI. While prioritizing the risk factors for osteoporosis commonly used in the general population, applying the SCIM score in the chronic phase may provide additional information on bone loss risk.

Microwave cavity antenna for automatic detection of chicken breast muscles affected by wooden breast defect

Over the past years, artificial selection for meat-type (broiler) chickens has resulted in improved production efficiency, but also in an increased incidence of skeletal muscle abnormalities. In particular, wooden breast (WB) abnormality causes abrupt changes in meat quality and enormous economic losses. Thus, the poultry processing industry requires a reliable method to detect the abnormality in production lines in a non-destructive and contactless way. The present research aimed to evaluate the effect of WB on dielectric properties to develop a potential online technique to distinguish unaffected from affected breasts. Sixty-five pectoralis major muscles were picked 3 h post-mortem from the same flock (42-day-old broilers, 2.8 kg average live weight) and classified by visual inspection according to their phenotype as normal (N, not showing not any signs of the WB condition; n = 33) or WB (exhibiting extensive hardened areas and stiffness perceived by manual palpation throughout the entire fillet; n = 32). WB muscles exhibited remarkably higher values of dielectric constant and loss factor in a wide range of the explored frequencies (200 MHz–14 GHz), suggesting higher water mobility and a higher solvate capacity; this makes the electromagnetic technique for classification promising. Based on the above evidence, a rapid microwave electric technique in the range 1.5 GHz–3 GHz was developed for the online detection of WB. Indeed, combining the use of a cavity antenna (vector network analyzer instrumental chain with partial least square – discriminant analysis), this technique correctly classified 100% of the validation test set.

A Universal Model for Ultrasonic Energy Transmission in Various Media.

This study presents a comprehensive model for ultrasonic energy transfer (UET) using a 33-mode piezoelectric transducer to advance wireless sensor powering in challenging environments. One of the advantages of UET is that it is not stoppable by electromagnetic shielding and can penetrate metal. Existing models focus on feasibility and numerical analysis but lack an effective link between input and output power in different media applications. The proposed model fills this gap by incorporating key factors of link loss, including resonant frequency, impedance matching, acoustic coupling, and boundary conditions, to predict energy transfer efficiency more accurately. The model is validated through numerical simulations and experimental tests in air, metal, and underwater environments. An error analysis has shown that the maximum error between theoretical and experimental responses is 3.11% (air), 27.37% (water), and 1.76% (aluminum). This research provides valuable insights into UET dynamics and offers practical guidelines for developing efficient wireless powering solutions for sensors in difficult-to-access or electromagnetically shielded conditions.

Influence of copper-coated graphene films on mechanical and damping properties of bionic laminar CuAlMn matrix composites

Inspired by the structure of nacre, bionic laminar composites composed of 85.6 wt% Cu, 11.9 wt% Al, and 2.5 wt% Mn were prepared using highly flexible Cu-coated graphene films as fillers. The effects of surface modification and graphene films content on the properties were investigated. Results indicated that the loss factor of composites with 0.1 wt% Cu-coated graphene films is improved by approximately 28% and reaches 0.044 compared to uncoated samples. The density and tensile strength are increased by up to 98% and 362 MPa, respectively. This enhancement is attributed to the improved bonding at the graphene films/matrix interface due to the Cu coating, which allows for efficient load transfer. Concurrently, the activation of interlayer sliding in the graphene films dissipates substantial energy. However, an excessive addition of graphene films leads to decreased density and increased internal defects in the composites, resulting in deteriorated properties. This study provides a reference for the preparation of CuAlMn matrix composites with enhanced mechanical and damping properties.

Patterns of KIR-genotypes in women with preimplantation losses after assisted reproductive technologies

Aim. To analyze the frequency and distribution of KIR genotypes in women with repeated preimplantation losses during ARTs compared to women with control group. Methods. DNA isolation from leukocytes by the salting method, PCR-SSP, agarose gel electrophoresis; methods of statistical analysis. Results. The molecular genetic determination of KIR genes in the group of women with recurrent implantation failures and in the control group of women was performed. The frequency and distribution of KIR genotypes in the study groups were determined. In women with RIF, a slightly shifted distribution of the frequency of KIR genotypes was found, towards the homozygous genotype by haplotype "A", the frequency of which was almost half of all identified genotypes (42.86 %). The distribution and frequency of KIR genotypes in the control group was normal and described by the Hardy-Weinberg principle. A comparative analysis of the study groups using statistical methods showed a significantly higher frequency of the KIR-AA genotype (χ2=8.875; p&lt;0.005) in the group of women with RIF compared to the control group of women. The calculation of the odds ratio indicates a 2-fold increase of risk for recurrent implantation failures after ARTs (OR=1.94; CI 95 %: 1.25–3.00) in women with the KIR-AA genotype. Conclusions. We regard the KIR-AA genotype as a significant risk factor for preimplantation loss. KIR genotyping is considered an important molecular genetic test for determining the risk of fetal rejection by the maternal immune system, which will help to correctly direct treatment interventions to keep the pregnancy alive.