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Are radiologists and radiological technologists
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Int. J. Low Radiation, Vol. 7, N o. 3, 2010 167

Are radiologists and radi ological technologists at
greater risk of rep roductive health problems? Data
from seven provinces in Iran
S.M.J. Mortazavi*
The Center for Radiological Research
School of Paramedi cal Sciences
Shiraz Un iversity of Med ical Scien ces
Shiraz , Iran
and
Radiology Dep artment
School of Paramedi cal Sciences
Shiraz Un iversity of Med ical Scien ces
Shiraz , Iran
E-mail: mmort azavi@sums.a c.ir
*Corresponding author
M.R. Sabetghadam, A. Arvin, Sh. Vatanpour,
F. Sabetghadam, M. Tirandaz
and E. Molazemhagh
The Center for Radiological Research
School of Paramedi cal Sciences
Shiraz Un iversity of Med ical Scien ces
Shiraz , Iran
E-mail: mr.sabetg hadam@y ahoo.com
E-mail: ali_ arvin [anonimizat]
E-mail: shv [anonimizat] m
E-mail: if_52 [anonimizat]
E-mail: mary amutopia@g mail.co m
E-mail: elahe _molazemha gh@ya hoo.com
Abstract: Many radiation work ers believe that occup ational exposures have
the po tential to interfer e with their norm al reproductiv e func tion. In this study ,
a total of 621 radiation workers (336 fe males and 285 males) who worked in
hospitals/clinics in seven differ ent provi nces were rando mly se lected. Al l the
participan ts wer e interviewed and the re ports of their pr evious exposures, as
recorded by film badge, ther moluminesc ent dosimeter or pen dosimeters, were
inves tigated. Only 47 particip ants (7.57%) had a his tory of receiving dos es
above the b ackg round lev el. Th e over all prevalence of spont aneous abortion,
stillbir th and congenit al abnor malities w ere 10.67%, 1 .21% and 1 .71%,
respectively . The rat es of occu rrence of at least one life time disorder for
spontaneous ab ortion, st illbirths and congen ital abnorm ality in 238 fem ale
radiation workers who had a history of prev ious pregnancy were 20.17% ,
3.12% and 4.47 %, respectively . Among 238 female rad iation workers who ha d
a history of pr evious pregnan cies, 79.83 % had no history of spontaneous
Copyright © 2010 Inderscience Enterprises Ltd.

168 S.M.J. Mortazavi et al.

abortion while 13.02%, 5.88% and 1.26% had one, two and three or mor e
previous abortio ns. The boy/g irl ratio in children born to male and to female
radiation worker s were 1.10 and 1.03, respectiv ely. It can be concluded that th e
occupational ex posures of rad iologist s and radiological technologists to
common levels of ionising radiation canno t significantly affect their
reproductive health.
Keywords: radiologists; r adiological technologists; reprodu ctive health ;
pregnancy outco mes; Ir an.
Referen ce to t his paper shoul d be mad e as follows: Mortazav i, S.M.J.,
Sabetghad am, M .R., Arvin , A., V atanpour , Sh., S abetgh adam, F., Tirand az, M.
and Molazemhagh, E. (2010) ‘A re radio logists and radiologica l technolog ists at
greater risk of r eproductive h ealth pr oblems? Data from seven provinces in
Iran’, Int. J. Low Radia tion, Vol. 7, No. 3, pp.167 –174.
Biographical n otes: S.M.J. Mortazav i hold s the position of Associate
Professor of Medical Physics in the School of Paramedical Sciences at Shiraz
Univers ity of Medical Sciences (SUMS), Iran. He als o serves as the S ecretary
for Res earch at The C enter for Radiologi cal Research. Since 1996 he h as been
studying the health ef fects of lo w doses of ionis ing radiation an d phenomena
such as radiatio n hormesis and radioad aptive response. He has authored mor e
than 60 p eer-r eviewed p apers in the area of natural rad iation, rad iation
hormesis, r adioadaptive r esponse and the po ssible role of radioad aptive
response in r adiation protec tion. He has also published pap ers on the futur e role
of radio adaptation in th e long- term stay of humans in space. He was previously
affiliated with t he Nation al Radiation Protectio n Department ( NRPD) of the
Iranian Nucl ear Regulato ry Auth ority, where he served as the secretary of the
Commit tee for High Backgroun d Radi ation Areas.
M.R. Sabetghadam, A. Arvin, F. Sabetgh adam, M. Tir andaz, and
E. M olazemh agh are rad iology students affiliated with th e student res earch
commi ttee at The Cent er for Radiologi cal Re search, Shiraz Univers ity of
Medical Sciences, Shiraz, Iran.
Sh. Vatanpour is a statisti cian aff iliated with th e student research commi ttee at
The Cent er for Radiologi cal Research, S hiraz Univers ity of M edical Sciences,
Shiraz, Iran. She received he r Master’s deg ree in Statistics from S hiraz
University. She has contribu ted to many research projec ts at The Cent er for
Radiological Research.

1 Introduction
The a dministration of various radi ological procedures has led to the exposure of a l arge
number of professional and techni cal pers onnel in medicine, de ntistry and vet erinary
medi cine to ionising radiation. However, radiologists and radi ological techn ologists are
among the earl iest groups occupationally exposed to ionising radiation (Yoshinaga et al.,
2004). A wide variety of individual an d envir onmental factors affect th e complex pr ocess
of human re production. In this light, it is n early impossi ble to accurately assess the role
of occ upational exposures t o ionising and n on-ionising ra diations on re productive
disorders su ch as spon taneous abo rtion, genetic disease or co ngenital abn ormalities.

Are radiation workers at greater risk of reproductive heal th problems? 169

Although the maxi mal risks attributed to commo n occ upational exposures are usual ly
orders of magn itude smaller th an th e spontan eous risks of abortion, malf ormation s, or
genet ic disease, radiation w orkers usually believe that occupat ional exposures ha ve the
potential to interfere wit h their no rmal rep roductive fun ction. Both maternal an d paternal
expos ures affe ct fetal developme nt. Maternal exposure to hazardo us agents from the
formation of an ovum c ell at the first month before conception to the gene ration of a
mutation, esp ecially in the first trimester of th e pregnancy, may alter th e outcome of
pregnanci es (Shi and Chia, 2001). M aternal exposure to ionising radiation during
pregnanc y has been linked to spontaneous abortion. On the other hand, maternal exposure
to teratogenic agent s during organogenesis is reported to be t he best-known causative
pathway for producing birth defects (Le masters, 1998).
As to paternal expos ures, even though the causative mec hanisms are unclear, the re
are repo rts indicatin g male-med iated developmental effects to the foetus (Sev er, 19 98;
Schrader and Lemaster s, 199 8; Silbergeld et al ., 2003). The mech anisms pro posed for
these effects, a lthough not cl early understood, include pat ernal prec onception exposure to
agents that resu lts in tran smissib le genetic alteratio ns or effects t hrough epigenetic
mechanisms, and the transmission of chemicals from t he fat her to the conce ptus via
semin al fluid. Although it h as rep eated ly been reporte d that paternal occupations such as
janitors, painters, printers, and other occupations exposed to solvents; firefigh ters; and
occu pations related to agricult ure a re ass ociated w ith birth defect s (Chia and Shi , 2002),
there are no re ports re peatedl y indicating a link bet ween paternal occupational exposure
of radiation workers to ionising radiation and birth defect s.
Miscarriag e or spontaneous abortion is th e loss of a pregnanc y before the foetus is
born. This usually hap pens within the first 20 weeks of pregnanc y. According to the
World Heal th Organization (WHO), about 15% of all clinically reco gnisable pregnancies
end in a s pontaneous abortion, 50% to 60% of which are linked to chromosomal
abnormalities (WHO, 199 4). When fetal death occurs after 20 week s of pregnancy, it is
called ‘stillb irth’. Mo st still births occur in full-term preg nancies. The p revalence of
stillb irths at th e commu nity lev el rang es from 0.3% to 0 .5% in some h igh-income
countries, to 5% in many low- and midd le-income co untries (Darmstad t et al., 2009).
A population-based re gistry has indicated that about half of congenital anomal ies had
a genetic aetio logy (Baird et al., 1988). It has b een reported that ap proximately 3%–5%
of all births resu lt in congenital malf ormation s (McK usick, 1998). Congenita l
malformation is a perma nent physical defect prese nt in a bab y at birth. This defect
may be ca used by genetic factors or by non-genet ic prenatal events. In a mal formed
infant, the development of a stru cture is arrested , delayed or misd irected . Congenital
malformations are a maj or cause of perinatal and neo natal death (N aeye, 1979).
Congenital malformations can be di vided into three cat egories: those ca used by genet ic,
environmental and unknown factors. It should be noted that the cause of a majority of
human malfo rmatio ns is unkn own. The US Cen ters for Disease Con trol and Prevention
(CDC) defines gross or severe congenital malformations as birth defects that cause death,
hospitalisatio n or men tal retard ation; necessitate sig nifican t or rep eated surgical
procedures; are disfiguring; or interfere wi th physical performance.
No published paper has evaluated the associ ation of occ upational exposures of
Iranian radiologists and radiological technologists with pregnancy outcomes such as
congenital ano malies or sp ontaneous abortion. T he aim of the prese nt study was t o
exami ne the relationshi p between occu pational exposures and pregnancy outcomes.

170 S.M.J. Mortazavi et al.

2 Methods
A total of 621 r adiation workers (336 females an d 285 males) who worked in different
hospitals an d clinics in Fars, Kerman, Bou shehr, Yazd , Koh gilooy eh, Ko rdestan and
Hormozgan provinces in Iran were randomly selected . All the particip ants were
interviewed a nd the reports of t heir previous e xposures, as rec orded by film bad ge,
Ther moluminescent Dosi meter (TLD ) or pen do simeters, we re investigated. Dat a
regarding gestational age, se x, mat ernal age and pa rity, type of del ivery, pe rinatal care,
obstetric history for any disease or medication during all past pregnanci es, consanguinity
of parents and history of congenital malformations for eac h birth were recorded.
3 Results
Among the participants, there we re 406 technologists, 138 radiologists and 77 nurses
aged 18–70 (mean ± SD: 35.96 ± 9.00). Female participants were 18– 67 years of age
(mea n ± S D: 34.13 ± 8.14; 50% over 33 years , and 25% over 39 years). The mean
week ly work time o f the particip ants an d their work experi ence in months in the field of
radiology were 39.70 ± 23.17 hours and 105.47 ± 101.62 months. Only 47 participants
(7.57% ) had a history of recei ving doses a bove th e background. Among the 70.5% of the
radiation workers w ho we re marri ed, 21% had c onsanguineous ma rriage. No associ ation
was found between consangu ineous marr iage and preva lence of s pontaneous a bortion
or stillb irth. Ho wever, the congenital ma lformation rate in consanguineous marriages
was sign ificantly higher th an that in unrelated families (p = 0.006). As to the job
of the radiation worker’s s pouse, 13.6% of the participants had a sp ouse w ho was a
radiation wo rker.
Only 18 particip ants (2.90%) repo rted a tempo rary sterility . The overall p revalence
of spontaneous ab ortion , stillb irths and con genital ab normalities were 1 0.67%, 1.21%
and 1.71 %, respectiv ely ( Table 1) . The rates of occurrence of at lea st one lifetime
disorder for spo ntaneous abortio n, stillb irths and congenital abn ormality in 238 female
radiation workers w ho had a hi story of previous pregnancies were 2 0.17%, 3.12% a nd
4.47%, re spect ively. On the other hand, the rates of occ urrence of at least one lifeti me
disorder for spo ntaneous abortion, stillb irths and congenital ab normality in 133 wives of
male radi ation wor kers who had a hi story of previous preg nancies were 2 1.81%,
3.31%, and 4.17%, respect ively. Among 238 femal e radiation w orkers who ha d ha d
previous pregnanci es, 79.83% had no history of spontaneous abortion whi le 13.02%,
5.88%, a nd 1.26% ha d one, two, and three or more abortions. As t o the 133 wives
of male radi ation w orkers w ho ha d a history of pre vious pregnancies, 78 .19% had n o
history of spontaneous abortion while 17.29%, 3.78% a nd 2.26% had one , two, and
three or more previous abortions. No case o f childhood can cer was observed. The
prevalence of reproductive diso rders when both partne rs in a ma rriage were radiation
workers was no t significan tly higher than when only one of the part ners was a radiation
worker. Th e boy/girl ratio s in children born to male an d female rad iation work ers were
1.10 and 1.03, respect ively.

Are radiation workers at greater risk of reproductive heal th problems? 171

Table 1 Prevalen ce of r eproductiv e disor ders in radiation workers and the general public
Reproductive
problem General public
(Global) General public ( Iran) Radiogra phers
(UK) Present
study (%) Present study*
Miscar riage
(spontaneous
abortion) 15% ( WHO,
1994)
33% after the
age of 40 years
(Modell et al.,
1992) 12% ( Roman
et al., 1996) 10.67 20.17% ( female
radiation
workers)
21.81% ( wives
of male
radiation
workers)
Stillbirth 0.3%–0. 5% in
high- incom e
countr ies
Up to 5% in
low- or
middle-income
countr ies
(Darmstad t
et al., 2009) 1% ( Roman
et al., 1996) 1.21 3.12% ( female
radiation
workers)
3.31% ( wives
of male
radiation
workers)
Congenital
malformation 3%–5%
(McKusick,
1998) 3.1% ( 2.0%
non-consan guineo us
marriages and 7. 0%
consangui neous
marriages)
3.09% ( Mosayebi and
Movahedian, 2007 )
1.04%
(Shamohamm adi and
Ahm adi, 1997)
3.5% ( Farhud et al.,
1986)
2.02% ( Ahmadzad eh
et al., 2008) 1.71 4.47% ( female
radiation
workers)
4.17% ( wives
of male
radiation
workers)
Note: *Occurrence of at least one repr oductiv e disorder.
4 Discus sion
In this survey, amo ng a wide vari ety of disorders which are referred to as ‘re productive
problems’, sterility , miscarriag e or ab ortion , stillb irths, and con genital malformations
are studie d. It should be not ed that as th ese problems occur c ommonly in the gene ral
population, it is n ot easy to find a link b etween environ mental facto rs an d these
disorders. Prenatal expos ure to ionising radiation can i nterfere wi th embryonic and fet al
developmen t. This interference d epends on bo th the dose and gestatio nal ag e at wh ich
exposure occu rred (De Santis et al ., 2007). Numerous st udies have indicated that t he
foetus is particularly vulnerable to the effect s of i onising radiation, es pecially duri ng the
first three m onths of gestation.

172 S.M.J. Mortazavi et al.

In this stud y, the rates o f occurrence of at least one life time disorder for spontaneous
abortion , stillb irths and con genital abnor mality were 2 0.17%, 3.12%, and 4.47%,
respect ively. These rat es in wives of ma le radiation workers who had a history of
previous pregnan cies w ere 21.81%, 3 .31% an d 4.17%, resp ectiv ely. I t should be noted
that th e rate of co ngenital malfo rmation in Iran is estimated to b e about 3.1% (2.0%
amon g neonates from no n-consangu ineous mar riages and 7.0% from co nsangu ineous
marri ages). Furthermore, in general 20% of the pregnancies have been reported to lead t o
spontaneous abortion. Also, it has been reported that in less devel oped countries 1.17% of
births are stillb irths while its prevalence in developed countries is 0 .5%. Three differen t
studies performed in Iranian cities Kash an, Ar ak and Tehran h ave shown a prevalen ce of
3.09% (M osayebi and M ovahedian, 2007), 1.04% (Sh amohammad i and A hmadi, 1997)
and 3. 5% (Farhud et al., 1986) for con genital malfo rmation s, respectivel y. A more rece nt
Iranian st udy performed in Ahwaz indicated a rate of 2.02% (Ahmadzadeh et al., 200 8)
for con genital malfo rmatio n (Tab le 1). Th e prevalence o f con genital ab normalities
amon g rad iation workers in our stud y is a li ttle mo re than the abov e-mentio ned rates in
Iran. The higher rate of cong enital malforma tion in children born to radiation wo rkers
compared to those of the general public may be due to t he fact th at, in our stud y, a
relativ ely large p roportion of ch ildren were born to relativ ely old mothers. Pub lished
reports indicate that after the age of 35 ye ars, the inci dence of chromosomal disorders
and s pontaneous ab ortion increases ra pidly with maternal age (M odell et al., 1992 ). It has
been re ported t hat after t he age of 40 years , over 33% of reco gnised pregnancies lead to a
miscarria ge (Modell et al ., 19 92). In our study, the proportion of marri ed radiation
workers who had a consanguineous marriage was 2 1%. Consanguineous mar riages are
reported to play a majo r role in the occurrence o f cong enital malfo rmatio ns (Hu dgins and
Cassid y, 2006). Th e overall rate o f consangu ineous mar riage in Iran was repo rted to be
38.6% (Saadat et al., 2004).
Our findings regarding the frequencies of reproductive disorders in radi ologists and
radiological te chnologists are n ot in line with those reported by Roman et al. (1996). In
their stu dy on British radiograph ers, among the 9208 reported preg nancies, 83 % were
live births, 12% were abo rtions, 1% were stillb irths, and 1% were o ther rarer spon taneous
adve rse e vents (ect opic pregnanc y, blighted ovum and hydatidiform m ole). The higher
prevalence of abortion s and stillb irths in our study may be due to th e fact that the British
study was o nly limited to radiographers, while radiologists and radiological techn ologists
who were involv ed in duties other than radiography were inclu ded in our study.
As to the risk of having a child with a congenital anomal y, no si gnificant differe nce
was found between male and f emale radiation wor kers. This find ing is in line with th at of
Roman et al. (1996), who re ported a sl ight difference between me n and wome n in the
frequency of adverse reproductiv e disorders other than med ical ter minations – 3.1% and
1.4% for wo men and men, resp ectiv ely. It is ev ident that rad iation has the potential to
alter cells, p articularly DNA (Parker, 1985), and DNA damag e is mor e likely to occur
during meio tic division than during inactiv e periods. Th is is the rationale for th e idea that
males may be at higher risk than fe males for dama ge caus ed by radi ation in germ cells;
from the time o f sexu al matu rity, spermat ogonia und ergo multiple mi totic d ivisions
(Connor and Fer guson-Smith, 1987).
In this study, only 47 pa rticipants (7.57% ) had a history of recei ving doses above
0 mSv. In this light, it was i mpossible to find any correlation between the mag nitudes of
the doses recei ved by radiation workers and birth defects.

Are radiation workers at greater risk of reproductive heal th problems? 173

5 Conclusion
Occup ational exposures, ev en to low do ses of X-rays during reproductive life, raise fears
and dilemmas about the possibility of having children with congenital an omalies. Th ese
fears are not limited to lay people, and educated radi ation wor kers suc h as radi ologists
and ra diological technol ogists may ha ve so me mi sconceptions re garding the rep roductive
risks of occupatio nal expo sure to low lev els of ion ising radiation. Based on the results
obtained in this stud y, it is ev ident that occup ational exposure of radiologists and
radiological techn ologists to comm on levels of i onising radiation can not significantly
affect their reproductive he alth. Counselling of femal e radiologists and radi ological
techn ologists of rep roductive age by expert radiation biologists and health physicists
could help them to plan their family size with out any irration al fear o f radiation .
Counsellin g before an y planned conception or during pregn ancy is esp ecially advised.
Acknowledg ements
The aut hors thank t he students who helped them with interviews and data collectio n in
diffe rent provi nces. The y are also grateful to all rad iation wo rkers who particip ated in
this stud y.
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