The Risk of Reproductive Disorders Among Information and Communication Technology Specialists Specialists: Literature Review

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Modern information technologies and automation of work processes with the help of information systems are integrated into the professional activities of specialists all over the world. This fact causes an increase in the number of workers with intensive use of information and communication technologies (ICT specialists), which include managers and highly qualified specialists in the field of financial, economic and administrative activities, sales, marketing, development, social services, as well as physicists and chemists, architects, designers, topographers and designers, faculty and staff of higher education institutions and others [1]. Characteristic features of working at a computer are prolonged sitting [2, 3], exposure to electromagnetic radiation [4, 5], work stress [6], which can be potential risk factors for reproductive disorders [7, 8, 9, 10]. Reproductive health is an important part of overall human health, which is one of the national goals, expressed in preserving the population, strengthening health and improving the well-being of people. Despite the fact that in the 1970-1990s a series of studies were conducted, as well as a meta-analysis on reproductive disorders among those working with computers, significant changes in the technologies used, work organization, and risk factor assessment methods determine the need to analyze this problem at the present stage. This review is devoted to the analysis of publications on reproductive disorders and key risk factors associated with the conditions of the production environment and the work process, capable of having a negative impact on the reproductive health of ICT specialists, taking into account the transformations in this field of activity.
Objective of the study: systematization and analysis of publications on reproductive disorders and their risk factors among ICT specialists in a historical perspective to identify current problems and approaches to the study of reproductive health disorders at the present stage.
Materials and methods. To achieve the goal of the review, publications were selected and analyzed that studied the production environment, work process and health of workers who intensively used ICT. Literature sources were found using the PubMed text database of medical and biological publications using MeSH terms and the eLibrary scientific electronic library using keywords and reference lists. The following MeSH terms were used for the search: computer terminals, computers, reproductive health, reproductive system, abortion, fertility; and keywords: video display terminals (VDTs), birth defects, abortions, preterm birth, infertility. Meta-analyses, systematic reviews, cohort studies, case-control studies, and the most significant cross-sectional studies were selected from the found sources - a total of 18 publications. Results. A possible association between the use of VDTs and an increased risk of pregnancy pathologies and birth defects began to raise concern in the 1970s, which was due to the identification of clusters of spontaneous abortions and birth defects in the fetus among women who worked with VDTs during pregnancy in the USA and Canada [11]. Such cases were most often recorded in organizations that began to actively use computer technology, for example, in newspaper editorial offices and telephone companies. These observations served as the basis for conducting studies aimed at studying the possible relationship between work with VDTs and such disorders as spontaneous abortions, premature births [13, 14, 14, 15], birth defects [11, 14], low birth weight of the fetus [11], and fetal death [11, 14]; a description of the results of the studies is presented in Table 1.
Kurppa K. et. al. (1985) [17] conducted one of the earliest studies devoted to birth defects of the fetus based on data from the National Registry of Congenital Defects retrospectively. Data were collected from mothers who worked with VDTs from the beginning of pregnancy, during an interview at the first postpartum visit to the doctor. The level of exposure was then divided into exposure less than 4 and more than 4 hours per day in the first trimester of pregnancy. As a result, no reliable association was found between work with VDTs and congenital anomalies of the fetus. In the study by Ericson A. and Källén B. (1986) [18], data were collected from a medical registry, and cases of births with birth defects and cases of spontaneous abortion were selected for analysis, VDT exposure was assessed using a questionnaire. A special feature of this study is the inclusion of such cofounders as smoking and work stress. As a result, unadjusted data showed an association between work with VDTs and congenital defects, the risks of which increased with increasing duration of work with VDTs during pregnancy, but no increased risk of spontaneous abortion was found. Subsequent adjustment for cofounders revealed that the risk of birth defects was associated with work stress, smoking, and social status. Several more studies were conducted later, which provided evidence of a possible increase in risk for those working 15 hours [13] and 20 hours per week [14], while more recent studies have not found an association between the use of VDTs and pregnancy pathologies. One such study is the Canadian cohort study led by McDonald A.D. et al. (1988) [13], which studied the effect of working with VDTs on the risk of a group of outcomes: spontaneous abortion, fetal death, congenital defects of various systems, and premature birth. A feature of this study is the collection of data on the previous and current pregnancy separately. According to the results, the risk of premature birth and fetal death did not differ for the group using VDTs compared to the control group, but an increased risk of spontaneous abortion and congenital defects of the genitourinary system was found. The authors explained these results as random findings and did not agree with the results obtained. The lack of a clear understanding of the effect of VDT exposure on the development of pregnancy and fetal pathologies was the reason for the need to combine the results. The meta-analysis of Parazzini F. et al. (1993) [11], which combined data from nine case-control studies [14, 15, 16, 17, 18, 19, 20, 21, 22] with a total of 61,414 participants, did not reveal statistically significant differences in the frequency of spontaneous abortions and low fetal weight between the groups of women working with VDTs and the control groups. A retrospective case-control study conducted by NIOSH (National Institute for Occupational Safety and Health in the United States) also did not reveal a connection even when taking into account the duration of work at VDTs: more than 25 hours a week of work at VDTs did not increase the likelihood of spontaneous abortions [22]. Early studies lacked precise data on the duration of exposure to the risks associated with computer work. Most studies focused on the time spent interacting with VDTs, which was used to assess exposure and was determined from interviews or job descriptions. Further analysis showed that the results of early studies may have been biased by random errors, such as the use of subjective assessment methods such as interviews, which led to an overestimation of the duration and frequency of VDT use among women with adverse pregnancy outcomes. In addition, in a number of studies [17, 18, 19], after accounting for work stress factors and smoking, the risk of spontaneous abortion did not differ between VDT users and control groups, indicating that the influence of work stress rather than VDT use itself is more significant.
For a long time, VDT use has raised concerns due to factors related to the technical features of monitors, primarily the possible influence of ionizing and non-ionizing electromagnetic radiation from the devices. The main concerns about the potential impact of VDTs on reproductive damage were mainly related to the then used method of generating images on the screen, based on the use of a cathode ray tube (CRT), which is a potential source of bremsstrahlung x-rays [24]. Companies that introduced computers into the production process were concerned about the possible impact on the health of workers. In response to a request from the Newspaper Guild and the New York Times to assess the possible radiation hazards to which newspaper employees working with VDTs might be exposed, measurements of electromagnetic radiation were made. The first detailed measurements of radiation emitted by VDTs were made by Moss et al. [25], Cox [26], Terrana et al. [27], the Bureau of Radiological Health [28], NIOSH [29]. All studies came to the same conclusion: levels of all types of electromagnetic radiation - x-rays, ultraviolet, visible, infrared, and radio frequency radiation, including microwaves - were well below established occupational and environmental safety standards. In 1981, the U.S. Department of Health and Human Services, Bureau of Radiation Health, conducted a survey and evaluation of electromagnetic emissions from VDTs [28]. What was unique about their measurements was that they measured emissions from 91 units of VDT models from all known manufacturers then in use in the United States, all of which were tested under conditions designed to maximize emissions. These conditions included artificially induced component failures, improperly adjusted service controls, and improperly adjusted user controls. As a result, 8 of the 91 units tested under severe conditions for ionizing radiation exceeded the 0.5 mR/h standard for x-rays, but under normal operating conditions, no x-rays were detected from any of the 91 units.

The results of the study of electromagnetic radiation from VDTs have shown that these devices are a source of low-intensity electric and magnetic fields in the ranges of 5 Hz - 2 kHz and 2-400 kHz [4, 5, 30, 31, 32]. Despite the lack of a general connection between computer work and pregnancy complications, the study by Lindbohm M.L. and co-authors [33] revealed an increased risk of spontaneous abortions in workers who used video terminals with a high level of extremely low-frequency magnetic fields (> 0.9 μT) compared to those who worked with terminals with a low level of magnetic fields (< 0.4 μT). However, according to the review by Delpizzo V. (1994), VDT operators are at no more risk than the general population [34]. For a long time, Russian legislation has maintained restrictions on computer work for pregnant women, which was expressed first in a complete restriction of such work (from 1996 to 2003), then no more than 3 hours per work shift (from 2003 to 2021). Such restrictions were not introduced into the new legislation with the advent of more modern devices - liquid crystal displays, the operation of which is based on the polarization properties of crystalline molecules used to create a visible image, which are not a source of X-ray radiation [35]. One of the characteristic features of the work of ICT specialists is work stress, which is expressed in limited time for solving work tasks, namely, in a lack of time and overtime work: according to Eurofound estimates, on average, ICT specialists worked 50 hours a week, 6 hours on Saturdays and Sundays, as well as during illness [3, 36]. Also, high work demands, low control over work, and low social support are determined among ICT workers [2, 6, 36]. Such work organization as lack of breaks, overtime work, night shifts, and involvement in the work context during rest periods influenced health disorders among ICT workers [2, 38, 38, 40]. As mentioned earlier, work stress can be one of the risk factors for reproductive disorders [7]; the increased risk found in early studies was associated with severe work stress during the period of mass transition to new computer technologies [18, 19, 20].
The organization of work when working with computers involves prolonged sitting of the worker, which is a potential risk factor for reproductive disorders [8]. The characteristic constant stay in a sitting position allows us to assume an increased risk of reproductive disorders among those working at the computer, however, in the available literature, taking into account the search methodology described above, such studies were not found. Despite the lack of convincing evidence of an increased risk of pregnancy pathologies and congenital developmental thresholds, some studies indicate possible links between working with VDT and fertility disorders. This area is the focus of next-generation studies on reproductive disorders in computer workers, the results of which are presented in Table 2. Among women, such disorders were manifested in a decrease in the thickness of the endometrium [39], the development of endometriosis and infertility associated with the cervical factor [40]. In the work of Alekseev O.G. (2008), women who worked with VDT were compared with the control group throughout the menstrual cycle. As a result, it was revealed that in the group of computer workers there was a high risk of menstrual cycle disorders such as suppression of gonadal function, which was expressed in such manifestations as amenorrhea and hypomenstrual syndrome, as well as in changes in the levels of sex hormones [39]. In men, changes in the volume of seminal fluid [41], a decrease in the viability and motility of spermatozoa were noted [43]. However, these results are not unambiguous, as we also found data showing that the risk of fertility disorders did not differ for those working with VDTs compared to a group of men who did not work with VDTs [44]. It is important to note that these studies are cross-sectional, which necessitates more evidence-based studies on the topic of fertility disorders associated with computer work, including prospective studies and subsequent meta-analyses.
Conclusion. Meta-analysis, as well as co-founder-adjusted risk estimates obtained in cohort studies and case-control studies, indicate that computer work is not associated with an increased risk of pregnancy or fetal pathologies. However, more recent studies show a probable association between computer work and fertility disorders among both women and men. In further studies, it would be appropriate to pay attention to the possible multifactorial etiology of such disorders, which may be associated with the work environment, technical devices, and the organization and content of work. In further studies, it is advisable to pay attention to the possible multifactorial etiology of such disorders, which may be associated with the work environment, technical devices, and the organization and content of work. For a more in-depth study, prospective studies using objective standardized methods are needed.

Tables

Table 1. Results of studies on reproductive disorders in workers with VDT

Disorder studied	Study Type	Sample	Results	Source
Congenital malformations	Meta-analysis that included 6 case-control studies [17, 18, 19, 20, 22, 23]	51777 women: 10,890 women used VDT at work, 40,887women did not use VDT at work	The risk of congenital malformations did not differ for the group of women who used VDT at work compared to the group of women who did not use VDT at work: OR = 1.0 (95% CI 0.9-1.2)	Parazzini F. et. al., 1993 [13]
	Case-control	820 cases: 723 cases of fetal birth without pathologies and violations of pregnancy, 97 birth defects. 575 women did not use VDT at work, 85 women used VDT <5 h/day, 83 women used VDT <5-20 h / day, 77 women used VDT >20 h / day	The risk of congenital malformations did not differ for the group of women who used VDT at work compared to the group of women who did not use VDT at work:   OR = 0.9 (95% CI 0.4-1.9) (for the working group <5 hours/day)   OR = 1.4 (95% CI 0.7-2.7 )( for the 5-20 h/day working group)   OR = 1.4 (95% CI 0.7-2.9) (for the working group >20 hours/day)	Goldhaber M. K. et. al., 1988 [15]
	Case-control	4731 women who used VDT, 22651 women who did not use VDT	The risk of congenital malformations in general did not differ for the group of women who used VDT at work compared to the group of women who did not use VDT at work:   RR = 0.9.4,94 (95% CI 0.78,78-1.1313)   The risk of having children with congenitalми порокmalformations of the urethra was higher for the group of women who used VDT at work compared to the group of women who did not use VDT at work:   RR = 1.8,84 (95% CI 1.01.007-3--,11.5)	McDonald A.D. et. al., 1988 [23]
Spontaneous abortion	Meta-analysis involving 7 case-control studies[18, 19, 20, 21, 22, 23, 24, 25]	60810 women: 6781 women used VDT in For example, 54029 women who did not use VDT at work	, the risk of spontaneous abortions did not differ for the group of women who used VDT at work compared to the group of women who did not use VDT at work: OR = 1.0 (95% CI 0.9-1.0)	Parazzini F. et. al., 1993 [13]
	Case-control	of 1078 cases: 723 cases of fetal birth without pathologies and violations of pregnancy terms, 355 cases of spontaneous abortion. 750 women did not use VDT at work, 106 women used VDT <5 h / day, 105 women used VDT <5-20 h / day, 117 women used VDT >20 h / day	The risk of spontaneous abortions did not differ for the group of women who used VDT at work compared to the group of women who did not use VDT at work. working hours:   OR = 0.9 (95% CI 0.6-1.4) (for the working group <5 hours/day)   OR = 1.0 (95% CI 0.6-1.6 )( for the 5-20 h/day working group)   The risk of spontaneous abortions was higher for the group of women who used VDT >20 hours / day compared to the group of women who did not use VDT at work:   OR = 1.8 (95% CI 1.2-2.8) (for the working group >5 hours/day)	Goldhaber M. K. et. al., 1988 [22]
	Case-control	4731 women who used VDT, 22651 women who did not use VDT	The risk of spontaneous abortion was higher for the group of women who used VDT at work compared to the group of women who did not use VDT at work: RR = 1.1919 (95% CI 1.09,09-1.3030)	McDonald A.D. et. al., 1988 [23]
	Case-control	191 cлуча- th spontaneousого abortiona and 394 births without pathologies in controlой groupse	, the risk of spontaneous abortion did not differ for the group of women who used VDT at work compared to the group of women who did not use VDT at work: HR = 1.11 (95% CI 0.7,7-1.66) The risk of spontaneous abortion was higher for the group of women who used VDT at work. VDT in the work compared to the group of women who used a video terminal with a high level of extremely low-frequency magnetic fields (>0.9 мкТлMKT) compared to women who used a terminal with a low level of these magnetic fields (<0.4 мкТлmkt): HR = 3.4 (95% CI 1.4–8.6)	Lindbohm M..L.. et. al., 1992 [36]
Symptoms of threatened abortion (bleeding with or without lower abdominal pain)	Case-control	1044 women: 1) 239 used VDT at work, 8.4 % of them had symptoms of threatened termination of pregnancy, 2) 805 did not use VDT at work, 9.8 % of them had symptoms of threatened termination of pregnancy	The risk of experiencing symptoms of threatened abortion did not differ for the group of women who used VDT at work according to compared to the group of women who did not use VDT at work: OR= 0.8 (95% CI 0.5-1.3)	Nurminen T, Kurppa K., 1988 [16]
Low fetal body weight	Meta-analysis that included 3 case-control studies [18, 23, 25]	23561 women: 4767 women used VDT at work, 18794 women did not use VDT at work	Risk of low fetal body weight It did not differ for the group of women who used VDT at work compared to the group of women who did not use VDT at work: OR = 1.0 (95% CI 0.9-1.2)	ParazziniF.. et. al., 1993 [13]
Fetal death	Case-control	4731 women who used VDT, 22651 women who did not use VDT	The risk of fetal death did not differ for the group of women who used VDT at work compared to the group of women who did not use VDT at work: HR = 0.82 (95% CI 0.47-1.33)	McDonald A.D. et. al., 1988 [23]
Preterm labor	Case-control	4731 women who used VDT, 22651 women who did not use VDT	The risk of preterm labor did not differ for the group of women who used VDT at work compared to the group of women who did not use VDT at work: HR = 1.08 (95% CI 0.98-1.18)	McDonald A.D. et. al., 1988 [23]
	Case-control	of 1044 women: 1) 239 used VDT at work, 3% of them had preterm labor, 2) 805 did not use VDT at work, 2.5% of them had preterm labor	The risk of preterm labor was different for the group of women who used preterm labor. VDT at work compared to the group of women who did not use VDT at work: HR = 1.2 (95% CI 0.5-2.7)	Nurminen T, Kurppa K., 1988 [16]

Note: OR is the odds ratio; RR is the risk ratio; CI is the confidence interval.

Table 2. Results of studies on fertility disorders in workers with VDT

Study disorder	Type of study	Sample	Results	Source
Female fertility	Case-control	281 women who used VDT, 216 women who did not use VDT	The risk of female infertility was higher for women who used VDT compared to the control group: OR = 2.21 (95% CI 1.22-4.01)  The risk of endometriosis was higher for women who used VDT compared to the control group: OR = 3.69 (95% CI 1.50-9.13)  The risk of infertility caused by cervical factor was higher for women who used VDT compared to the control group: OR = 2.65 (95% CI 0.99–7.12)	Smith E..M.. et. al., 1997 [48]
Нарушения Menstrual disorders		in 45 women with стаж continuous work experience with VDT >2 years, working 30 hours / week, 45 women in the control group	atthe same time, FSH was: 1)                   In the control group in the 1st phase of the menstrual cycle: 12.33±1.76, in the 2nd phase 8.72±2.32 iU/l and was в within the normal range. 2)                 In the main group , the level of FSH in the 1st phase of the menstrual cycle was 8.46±1.71 iU/l (p<0.05), inthe 2nd phase-6.87±1.23 iU / l по compared to the control group (p>0.05).	Alekseev et. al., 2008 [47]
Male fertility	Case-control	Men belonging to different professions: 650 cases of male factor infertility, 698 fertile men in the control group	The risk of male factor infertility did not differ for the group that used VDT in their work compared to the control group: OR = 0.30 (95% CI 0.13-0.68)	Gracia C.. R.. et. al., 2005 [51]
	Case-control	of 224 infertile men: 118 working with VDT and 106 representatives of other professions; control group-125 men with normal fertility	Sperm volume, viability and motility were significantly lower in infertile men working with VDTthan infertile men in other professions (p<0.05)   In the group, usingVDT >10 h/day, sperm density, viability, and motility were significantly lower than in the groupsusing VDT 0-5 h/day (p<0.05)	He J.. et. al., 2008 [50]]
	Cross-sectional	study of 100 men who used a laptop at work: less than 2 hours / day-41 men, more than 2 hours / day-59 men	The risk of abnormal sperm volume was higher for the group using a laptop >2 hours/day and the group using laptops 2-5 hours/day: OR = 15.9 (95% CI 2.5-103.2)	Sterling L et. al., 2024 [49]

Note: OR – odds ratio; RR - risk ratio; CI – confidence interval.

 

 

About the authors

Liliya M. Fatkhutdinova

Kazan State Medical University

Email: liliya.fatkhutdinova@gmail.com
ORCID iD: 0000-0001-9506-563X
SPIN-code: 9605-8332
Scopus Author ID: 6603587324
ResearcherId: C-4294-2016
https://kazangmu.ru/department-of-hygiene/sotrudniki-kafedry

MD, Professor, Head of the Department of Occupational Hygiene and Medicine

Russian Federation, 420012, Volga Federal District, Republic of Tatarstan, Kazan, Butlerova str., 49

Adelya R. Muhutdinova

Kazan State Medical University of the Ministry of Health of the Russian Federation

Author for correspondence.
Email: adelya.gigienist@mail.ru
ORCID iD: 0009-0002-5705-2007
SPIN-code: 8700-9716

Post-graduate student of the second year of study, assistant of the Department of Occupational Hygiene and Medicine 

Russian Federation, 420012, Volga Federal District, Republic of Tatarstan, Kazan, Butlerova str., 49

Nail Kh. Amirov

Kazan State Medical University of the Ministry of Health of the Russian Federation

Email: amirov@kgmu.kcn.ru
ORCID iD: 0000-0003-0009-9103

MD, Professor, Academician of the Russian Academy of Medical Sciences

Russian Federation, 420012, Volga Federal District, Republic of Tatarstan, Kazan, Butlerova str., 49

References

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