保健医療科学

2018 Vol.67 No.1 p.59－70

Topics: Lessons learned on public health from the Fukushima Daiichi Nuclear Power Plant accident＜ Review ＞
Overview of the pregnancy and birth survey section of the
Fukushima Health Management Survey:
Focus on mothersʼ anxieties about radioactive exposure
Shinya Ito 1), Aya Goto 2,3), Kayoko Ishii 3), Misao Ota 3,4), Seiji Yasumura 1,3), Keiya Fujimori 3,5),
for the Pregnancy and Birth Survey Group of the Fukushima Health Management Survey
1)

Department of Public Health, Fukushima Medical University School of Medicine

2)Center for Integrated Science and Humanities, Fukushima Medical University

3)

Radiation Medical Science Center for the Fukushima Health Management Survey

4)

Department of Midwifery and Maternal Nursing, Fukushima Medical University School of Nursing

5)

Department of Obstetrics and Gynecology, Fukushima Medical University School of Medicine

Abstract
Objectives: The aims of this study are (1) to review the Pregnancy and Birth Survey section of the
Fukushima Health Management Survey (FHMS); (2) to clarify the proportion of anxieties felt by mothersfrom Fukushima that relate to radiation exposure as a stigma in society, and also to identify associatedfactors; and (3) to explore the attitudes of future mothers from the region in regard to childbirth bydeveloping a new scale, known as the “Fukushima Future Parents Attitude Measure (FPAM).
Methods: (1) We reviewed 11 studies that reported using the FHMS Pregnancy and Birth Survey todetermine the health of infants and mothers. (2) To analyze levels of anxiety, we used the data from a 2011baseline survey and its 2015 follow-up, ascertaining the mothersʼ subjective health, depressive symptoms,
maternal confidence, and anxieties regarding radiation exposure. (3) Finally, to achieve our third aim, we
distributed a questionnaire to all 310 students at a womenʼs college in Fukushima Prefecture.
Results: (1) Analyses of FHMS data showed that the Fukushima nuclear accident did not affect pregnancy
outcomes, but did affect maternal mental health. (2) An examination of the surveys of mothersʼ mental
health revealed that 974 mothers (41.2%) reported having feelings of anxiety associated with the stigma ofradiation exposure. In particular, maternal age, depressive symptoms, receiving antenatal care as scheduled,and post-quake medical history were significantly associated with a higher proportion of anxieties related
to this stigma. (3) Exploratory and confirmatory factor analyses were conducted, allowing us to identify two
Factors: “caring for a baby” (three items) and “giving birth to a baby” (three items). Both factors correlatedwith the studentsʼ quality of life, self-efficacy, and self-esteem scales, and the factor, “giving birth to a baby,”
also correlated with radiation-related risk perception.
Conclusions: The FHMS highlighted the importance of providing mental health support to the mothersof young children. It should be particularly noted that over 40 percent of mothers in the follow-up study
in 2015 had anxieties about being stigmatized for their radioactive exposure. In addition, young womenʼs
attitudes toward future pregnancy, as measured by the FPAM, are associated with their radiation risk
perception.
keywords: Fukushima Health Management Survey, stigma, Fukushima nuclear accident, radiation, FPAM
(accepted for publication, 4th January 2018)
Corresponding author: Shinya Ito
2-1-1, Kitasato, Minami-ku, Sagamihara, Kanagawa, 252-0329, Japan.
Tel: +81 42 778 9382
E-mail: shinyai@nrs.kitasato-u.ac.jp

J. Natl. Inst. Public Health, 67 (1) : 201859

Shinya Ito et al., for the Pregnancy and Birth Survey Group of the Fukushima Health Management Survey

I．FHMS Pregnancy and Birth Survey
The Great East Japan Earthquake occurred on March
11, 2011, causing a tsunami to hit the Tokyo ElectricPower Companyʼs Fukushima Daiichi Nuclear Power Plant,
which resulted in the leakage of radioactive material.
Consequently, since this incident, many people in the area
have lived in fear of radiation exposure. In the aftermathof this major nuclear power plant (NPP) disaster, mothersof young children were identified as one of the groups atgreatest risk of experiencing negative emotional and mental
health consequences [1].
1. Methods
After the Fukushima nuclear accident, the Fukushima
Health Management Survey (FHMS) was planned andimplemented to monitor the physical and psychologicalhealth status of all prefectural residents [2]. Respondents
to the FHMS Pregnancy and Birth Survey were women
who registered as being pregnant at a municipal officeeither in Fukushima Prefecture or in another prefecture anddelivered their babies in Fukushima Prefecture on or after
March 11, 2011. In Japan, every pregnant woman is required
to register her pregnancy; she receives a maternal andchild-health handbook, as well as antenatal and postnatal
checkups and other services. The total number of women
meeting these criteria in 2011–2015 was 14,516–16,001;
of these, 6,866–9,316 returned the FHMS questionnaire(response proportion = 47.1–58.2%: Table 1).
The questionnaire, which can be seen on our website[3], was designed to obtain general demographic andperinatal outcome data, including maternal age, pregnancy
and medical history, pregnancy outcome, gestational age atdelivery, mode of delivery, and infant birth weight. We alsosought to ascertain mothersʼ mental health status, maternal

confidence, and the childʼs health status. The questionnaire
included a blank space for respondents to freely write theirown opinions.
The Ethics Committee of Fukushima Medical University
approved this study (No. 1317, 2333). The survey aims
were explained to all participants in a cover letter that
accompanied the questionnaire. By responding to thesurvey, participants were considered to have consented toparticipate.
2. Overview of results
Eleven previous studies were found to have used FHMS
Pregnancy and Birth Survey data [4-14] (as of November
2017; Table 2). Each of these studies focused on one oftwo main themes: (1) pregnancy outcomes, including
stillbirth, preterm birth, low birth weight, and congenital
anomalies; or (2) the mothersʼ mental health. In the 2011
data, the overall proportion of preterm (delivered at <37 gestational weeks) and low birth weight (< 2,500 g)
infants was almost the same as that reported in the national
surveillance data [4,12,15] (Table 1); furthermore, theprevalence of congenital anomalies in singleton pregnancies
across the five-year study period was almost the sameas the 2–3% prevalence reported in the general Japanese
population [12,16]. The earliest study of maternal mental
health reported that, in 2011, 28% of mothers screened
positive for depressive symptoms, measured using a twoitem screening test [5]. Although the prevalence gradually
decreased over our study period (27.1% in 2011; 25.5% in
2012; 24.5% in 2013; 23.4% in 2014; and 21.9% in 2015)[12], it remains higher than that reported, using the samequestions, in other regions of Japan. For example, in
Mishina et al.ʼs study, the proportion of mothers in Osaka(eastern metropolitan area) with postpartum depression was
19.8% at one month, and 1.4% at four months [17], while

Table 1 Survey population and characteristics of the infants
Survey Population
Response Proportion (%)
Preterm Delivery (%)
Survey Data
Reference Data
Low Birth Weight (%)
Survey Data
Reference Data
Congenital Anomalya (%)
Survey Data
Reference Data

FY 201116,001
58.2

FY 2012
14,51649.5

FY 2013
15,21847.7

FY 2014
15,12547.2

FY 2015
14,572
47.1

4.8
5.7

5.7
5.7

5.4
5.8

5.4
5.7

5.7
5.6

8.9
9.6

9.6
9.6

9.9
9.6

10.1
9.5

9.7
9.4

2.9
2.4

2.4
2.3

2.4
2.4

2.3
2.5

2.2
―

a

Data from singleton pregnancies.
Reference data relating to preterm deliveries and low-birth-weight infants were sourced from vital statistics recorded in Japan on an annual basis, whereas those relating to congenital anomalies
were sourced from the World Health Organization and Cleaning House International Monitoring
Center Japan Branch.
b

60

J. Natl. Inst. Public Health, 67 (1) : 2018

J. Natl. Inst. Public Health, 67 (1) : 2018

2011–
2014

2011 8,358 mothers

2011– 8,575 mothers in 20112013 6,921 mothers in 2012
7,022 mothers in 2013

Ishii et al. (2017a)12Ishii et al. (2017b)13

Ito et al. (2017)14―

2011 7,053 mothers whoto evaluate the obstetric outcomes in mothers in Fukushi- During the nine months before and after the disaster, 138 (2.0%)
conceived during the nine ma prefecture during and after the disaster.
and 102 (1.9%) women conceived using in vitro fertilization-embryo transfer (IVF-ET).
months before and after
Although IVF-ET was found to be associatedthe disasterwith increased incidence of cesarean sections and low
birth weight, there were no significant differences in obstetricoutcomes between the periods before and after the disaster.

Hayashi et al. (2017)11

to clarify the frequency of, and temporal changes, in thecontent of mothers' freely written opinions obtained in
the FHMS from 2011 to 2013.

to assess the health status of, and provide telephonecounseling, to mothers living in Fukushima after the
nuclear accident.

to review the major findings from four annual surveys
conducted from 2011 to 2014.

Common to the top five codes across the three years were the "effect of radiation on the fetus and infant" and "information provision, including survey results." Participants who wrote
free opinions were significantly more likely to be aged ≥ 30 years and to have depressive
symptoms.

Significantly most of the mothers who received telephone counseling had experienced interruptions in antenatal care, high-risk pregnancies with complications and/or anomalies, orcesarean sections, or were primipara. The most frequent topic discussed in the counselingwas "effects of radiation," followed by "mothers' health" and "childrearing."

Overall rates of preterm deliveries, low-birth-weight infants, and congenital anomalies in
the first year were almost the same as those reported in national surveillance data. Meanwhile, the prevalence of depressive symptoms among the mothers remained constant, atapproximately 25%, over the four years. Regarding the content of parenting counseling, theproportion of mothers who voiced concerns about radiation decreased each year.

to identify, at an early stage, the health problems of moth- The proportions of mothers with lower self-confidence in regard to child rearing and who
ers and babies and to help mothers become confident in experienced depressive symptoms were 53% and 25% in 2012 and 55% and 24% in 2013,
regard to parenting.
respectively. Evacuation and concern about radiation were significantly associated with depressive symptoms, but not lower maternal confidence, although these two outcomes weresignificantly associated.

2012 6,686 mothers in 20122013 6,423 mothers in 2013

Goto et al. (2017)10

The percentage of women who breastfed exclusively was 30.9%. The use of formula feeding
because of concerns relating to radioactive contamination was significantly higher in women
who had resided within the evacuation area and in those whose regularantenatal care had been interrupted.

2011 5.593 mothers who exto examine the association between changes, as a result Pregnant women who changed their perinatal checkup institution due to medical indication
perienced an earthquake of an earthquake, in medical institutions providing perina- were found to be significantly associated with shorter gestational duration and preterm birth
between the 4th and 37th tal care and gestational duration.
than women who visited only one institution.
weeks of their gestational
periodto assess the need for the provision of breastfeeding
support after a disasterSuzuki et al. (2016)9

2011 8,366 mothers

Ishii et al. (2016)7

to evaluate the mental health status of mothers who have Among the three fetal-loss groups, the proportion of positive depression screens was sigexperienced miscarriage, abortion, or stillbirth immedi- nificantly higher in the miscarriage and stillbirth group than in the childbirth group.
ately after experiencing a disaster.

2011 1,706 newborns
to evaluate the effects disasters have on feeding methods There were no significant differences in the backgroundcharacteristics of the newborns in these areas. When, to assess trends, birth dates were(Affected area: 836)
and growth in infants born after such events.
divided into four periods, no(Less-affected area: 870)
significant change in the exclusive breastfeeding rate wasfound; however, the exclusive formula-feeding rate was significantly
different across time periods in the affected area.

2011 61 miscarriages
5 abortions
22 stillbirths

Yoshida-Komiya et al. (2015)6

The incidences of stillbirth, preterm birth, low birth weight, and congenital anomalies were0.25%, 4.4% , 8.7%, and 2.72% , respectively. These incidences are similar to recent averages reported in other areas of Japan.

Main findings

to clarify depressive symptoms among new mothers, and Of the 8,196 women, 2,262 (28%) screened positive for depressive symptoms. Boththeir association with geographical region and interrup- mothers in Soso, the region in which the nuclear power plant is located, and mothers thattions in obstetrical care, who have experienced a disaster. had changed obstetrical care facilities were significantly more likely to screen positive fordepression.

to present some results sourced from a pregnancy andbirth survey performed using questionnaires and conducted after a disaster.

Aim of study

Table 2 Summary of the FHMS Pregnancy and Birth Survey

Kyozuka et al. (2016)8

2011 8,196 mothers

Goto et al. (2015)5

Number of analyzed
subjects

2011 8,602 mothers

Data

Fujimori et al. (2014)4

Study

Overview of the pregnancy and birth survey section of the Fukushima Health Management Survey

61

Shinya Ito et al., for the Pregnancy and Birth Survey Group of the Fukushima Health Management Survey
the Hamamatsu Birth Cohort reported a depression rate of
11% within one month, and 4% at 2–3 months postpartum[18]. As for the mothers who wrote their own commentson the questionnaire, during the first two years after the
nuclear accident, many mothers expressed concerns about
the health effects of radiation on their children; by the thirdyear, their concerns had shifted more toward their own
health and general parenting issues [14].

II．Follow-up Study of the FHMS Pregnancy
and Birth Survey
In Fukushima, there is a growing interest in the public
stigma and self-stigmatization associated with radioactive
exposure [19]. For example, many young women in
Fukushima Prefecture worry that others might view
them negatively, making assumptions about the effects ofradiation on their future pregnancies or genetic inheritance[20]. Consequently, evacuees often try to conceal thefact that they lived in Fukushima [20]. Prior research has
shown that self-stigmatization is often associated withpublic stigma [21], increased hopelessness [22], poorer
self-esteem [22,23], reduced self-efficacy [22,23], anddecreased quality of life (QOL) [22]. Despite these findings,
little has been done to address the public stigmatizationof pregnant women in Fukushima. In 2015, the FHMS
conducted a follow-up study on the women who contributed
to the baseline study in 2011, seeking to determine theongoing state of maternal anxiety associated with radiation
exposure, including perceptions of stigmatization. In
this section, we examine the factors associated with themothersʼ anxiety about stigmatization, using data from thisfollow-up study.
1. Methods
This study has used data from the baseline survey
performed in 2011 and the follow-up conducted in 2015.
The follow-up questionnaire was sent to 7,252 women who
responded to the baseline survey, where both mother andchild were confirmed as still living. In this later survey, wesought to ascertain the mothersʼ subjective health status,
depressive symptoms, maternal confidence, and anxieties
concerning radiation exposure (water, food, playing outside,
the child healthʼs, the stigma, genetic effects, and more).
To perform a statistical analysis, we first calculated thetetrachoric correlation coefficients for the mothersʼ anxiety
about the effects of radiation, and we also examined therelationship between this anxiety and the other items. Next,
the associations between the anxieties declared in 2015
and the mothersʼ background characteristics from 2011were examined using univariate and multivariate logistic
regression analyses. The Ethics Committee of Fukushima
Medical University approved this study (No. 1317, 2333).
2. Results
Of the 7,252 women targeted, 2,554 returned thequestionnaires (response proportion = 27.6%) and datafrom 2,365 women were analyzed; 189 participants were
excluded on the following grounds: delivering their babies
before March 11, 2011 (n = 96); and answers provided
by another person (n = 93). Of the valid responses, 974
mothers (41.2%) reported feeling anxious about thestigma. The results of the tests for correlations between
the anxieties regarding radiation and parenting concerns
are shown in Table 3. In particular, water of the anxieties
concerning radiation exposure showed medium and large
correlations with food (φ = 0.84), playing outside (φ =0.65), and child health (φ = 0.41). Meanwhile, food showed
medium and large correlations with playing outside (φ= 0.62) and child health (φ= 0.40). Child health showed
a medium correlation with genetic influence (φ = 0.41)
and disease in children (φ = 0.46). Finally, maternalage, depressive symptoms, receiving antenatal care asscheduled, and post-quake medical history were found to besignificantly associated with a higher level of anxiety about
the stigma (Table 4).

Table 3 Correlations between anxieties concerning radiation effects (follow-up data from 2011)
1
2
3
4
5
6
7
8
9

Water
Food
Playing outside
Child health
StigmaGenetic influence
Mental and physical development of children
Disease in childrenChildren's lifestyle

n
969
1,121
883
1,772
974
773
935
953
637

%
41.0
47.4
37.3
74.9
41.2
32.7
39.5
40.3
26.9

1

2
0.84
0.65 0.62
0.41 0.40
0.02 -0.01
0.31 0.28
0.11 0.14
0.29 0.28
0.13 0.14

3

0.37
0.08 -0.02
0.29 0.41
0.18 0.28
0.27 0.46
0.19 0.20* tetrachoric correlation

62

4

J. Natl. Inst. Public Health, 67 (1) : 2018

5

6

7

8

0.25
0.10 0.20
0.06 0.30 0.23
0.13 0.18 0.29 0.17

Overview of the pregnancy and birth survey section of the Fukushima Health Management Survey

Table 4 Characteristics of the anxieties relating to stigma concerning radioactive exposure (datafrom 2011)

Mother's age at the time of pregnancy(years; mean and SD)c
RegionKenpoku (North region)
Kenchu (Middle region)
Kennan (South region)
Soso (Coastal region)
Iwaki (Coastal region)
Aizu, Minamiaizu(Mountainous region)
Birth
0 (First-time mother)≥1
Breast-feeding on March 11
No
Yes
Depressive symptoms
Negative
Positive
Continuation of perinatal care and delivery
Yes
No
Attendance of antenatal care as scheduled
Yes
No
Prepregnancy disease
No
Yes
Disease between pregnancy and disasterNo
Yes
Post-quake disease
No
Yes
Sexd
Boy
Girl
Birth weight2500 g or higher
Less than 2500 g (low birth weight)
Congenital anomalyNo
Yes
Feeding method
Breast feeding only
Mix method
Bottle feeding only

Univariate analysisa

Multivariate analysisb

n
32.1

%
4.6

No anxiety
concerning
stigma(n = 1391)
n
%
31.4
4.9

259
297
64
118
143
93

26.6
30.5
6.6
12.1
14.7
9.5

376
364
89
118
262
182

27.0
26.2
6.4
8.5
18.8
13.1

1
1.19
1.04
1.45
0.79
0.74

0.95
0.73
1.08
0.61
0.55

-

1.48
1.49
1.96
1.03
1.00

0.000
0.132
0.814
0.015
0.077
0.048

671
259

72.2
27.8

938
384

71.0
29.0

1
0.94

0.78 -

1.14

0.536

930
26

97.3
2.7

1,307
57

95.8
4.2

1
0.64

0.40 -

1.03

0.064

821
140

85.4
14.6

1,222
145

89.4
10.6

1
1.44

1.12 -

1.84

0.004

744
226

76.7
23.3

1,135
243

82.4
17.6

1
1.42

1.16 -

1.74

0.001

769
204

79.0
21.0

1,164
216

84.3
15.7

1
1.43

1.16 -

1.77

0.001

855
118

87.9
12.1

1,234
149

89.2
10.8

1
1.14

0.88 -

1.48

0.308

816
155

84.0
16.0

1,185
200

85.6
14.4

1
1.13

0.90 -

1.41

0.309

753
212

78.0
22.0

1,145
226

83.5
16.5

1
1.43

1.16 -

1.76

0.001

493
469

51.2
48.8

701
672

51.1
48.9

1
0.99

0.84 -

1.17

0.927

909
56

94.2
5.8

1,265
108

92.1
7.9

1
0.72

0.52 -

1.01

0.055

909
25

97.3
2.7

1,300
27

98.0
2.0

1
1.32

0.76 -

2.30

0.317

316
604
54

32.4
62.0
5.5

405
911
71

29.2
65.7
5.1

1
0.85
0.98

0.71 0.66 -

1.02
1.43

0.186
0.075
0.896

Anxiety concerning stigma(n = 974)

95% CI

OR
1.03

Lower  1.01 -95% CI

P
value

P
value

OR

Upper
1.05

0.001

1.03

1
1.13
1.09
1.29
0.74
0.77

0.90 0.76 0.94 0.57 0.57 -

1.42
1.57
1.76
0.97
1.04

0.003
0.285
0.629
0.115
0.027
0.083

1
1.34

1.04 -

1.73

0.024

1
1.40

1.12 -

1.74

0.003

1
1.36

1.10 -

1.68

0.005

Lower  - Upper
1.01 1.05

0.001

a

Univariate logistic regression analysis by forced entry method.
In the multiple logistic regression analysis (forward selection: likelihood ratio), the independent variables featured items that, through univariate logistic
regression analysis, were found to have p values of less than 0.05: mother’s age at the time of pregnancy, region, depressive symptoms, continuation ofperinatal care and delivery, attendance of obstetric exams as scheduled, and post-quake disease; Cox-Snell R2 = 0.024; Nagelkerke R2 = 0.033.
cAge on April 2, 2011.
dThis analysis excluded data relating to twins (n = 20).
b

J. Natl. Inst. Public Health, 67 (1) : 201863

Shinya Ito et al., for the Pregnancy and Birth Survey Group of the Fukushima Health Management Survey

III．Young Womenʼs Attitude towards FutureChildbirth in Fukushima
In addition to assessing current mothersʼ anxiety using
FHMS, we further aimed to explore future mothersʼ
attitude towards childbirth; to achieve this we developed a
new scale, called the “Fukushima Future Parents Attitude
Measure” (FPAM).
1. Methods(1) Study design and participantsThis cross-sectional survey was distributed to all 310
students at a womenʼs college in Fukushima Prefecture,
Japan, in December 2015. Twenty-one participants were
excluded on the following grounds: being married (n = 3);
providing the same response to all of the questions (n =1); scoring at least 9 out of 10 on the Social Desirability
Scale (n = 9) [24,25]; and neglecting to report social
desirability scale values (n = 8). Consequently, a total of
289 participants were included in the final analysis.
(2) Scale development procedure
The items included in the FPAM were selectedfrom the following scales: the Perceived Devaluation
and Discrimination Scale [26,27]; the Internalized
Stigma of Mental Illness (ISMI) scale (Tanabe, personalcommunication, 2015) [28,29]; the BRCA Self-Concept
Scale [30]; the Boston University Empowerment Scale [31];and the Prenatal Self-Evaluation Questionnaire [32,33].
The selection criteria were that the scales were (1) globallyused, and (2) had established reliability and validity. Fourexperts (one psychiatrist, one clinical psychologist, and two
educational experts) participated in the item selection; anitem was selected when at least three of the four experts
independently estimated that it would be useful, resulting inthe selection of 27 items. The experts then independently
rated the usefulness of the items using a nine-point Likert
scale (where 1 = extremely useful, 5 = neither usefulnor useless, and 9 = extremely useless). Items that wererated between 1 and 5 on this scale were then collected,
and the experts chose the 10 they considered most useful.
When the experts judged that an item should be expressed
differently, one psychologist, one clinical psychologist, andone public health physician revised the wording of the item.
The 10 FPAM items are rated on a four-point Likert scaleranging from 1 (agree) to 4 (disagree). Before responding
to the items, participants are provided with the following
instruction: “Please answer the following questions. Pleaseassume that you will live and raise a family in Fukushima
Prefecture.”(3) Indicators of FPAM validity
To evaluate the validity of the FPAM, we used the64

following measures: the World Health Organization-FiveWell-Being Index (WHO-5) [34]; the Rosenberg SelfEsteem Scale (RSES) [35,36]; the General Self-Efficacy
Scale (GSES) [37]; the Social Desirability Scale; and items
for assessing perceptions of radiation-related health-effectrisks [4,38]. In addition, perceptions of risks relating to
the effects of radiation on health were evaluated using
two items sourced from screening measures included in amental health and lifestyle survey, developed as part of the
Fukushima Health Management Survey [2,38]. Specifically,
these two items are: “What do you think is the likelihood ofdamage to your health (e.g., cancer) in later life as a resultof your current level of radiation exposure?” and “What do
you think is the likelihood that the health of your future (i.e.,
as yet unborn) children and grandchildren will be affected
as a result of your current level of radiation exposure?”(4) Statistical analysis
A five-step analysis of the results was conducted.
First, to identify the factor structure of the FPAM among
participants, we conducted an exploratory factor analysis
with promax rotation, using maximum likelihood as theestimation method. Criteria for the retention of factors
were based on a scree plot and factor interpretability; foreach of the identified dimensions, scale items with loadings
greater than 0.40 were retained and used to construct thescale. Second, to assess the goodness-of-fit of the factor
model identified through the exploratory factor analysis,a series of confirmatory factor analyses were performed;
again, the maximum likelihood procedure was used toobtain estimates. Consequently, seven fit statistics wereused to determine the best model fit [39]. Third, to evaluate
the reliability of its internal consistency, we calculated
Cronbachʼs alpha coefficients. Fourth, to verify criterionrelated validity, Pearsonʼs or Spearmanʼs correlations
between the FPAM and each measure were calculated, as
appropriate. Finally, we conducted a multiple regression
analysis or an ordered probit analysis, using the forced
entry method. An ordered probit analysis is analogous toa multiple regression analysis; however, in ordered probit,
the dependent variable is scored on an ordinal scale,whereas in multiple regression, the dependent variable isscored on an interval scale. The full and two-item versionsof the FPAM were the dependent variables, and the WHO5, RSES, and GSES were the independent variables; Mplus
version 3.0 (Muthén and Muthén, Los Angeles, CA) wasused for the confirmatory factor analysis and ordered probit
analysis, while the other analyses were calculated using
SPSS version 21.0 (SPSS Inc., Chicago, IL).
(5) Ethical considerations
The Ethics Committee of Fukushima Medical University
approved this study (No. 2462). Prior to beginning the

J. Natl. Inst. Public Health, 67 (1) : 2018

Overview of the pregnancy and birth survey section of the Fukushima Health Management Survey
study, we obtained approval from the university andheld preparatory meetings with the studentsʼ teachers.
The teacher of each class distributed questionnaires
to the participants and collected them once they had
been completed. The survey aims were explained to allparticipants in a cover letter that was distributed with thequestionnaire; in particular, the cover letter stated thatstudents should return a blank questionnaire if they did
not wish to participate. We also indicated to students thatthe survey was anonymous, and that they would not suffer
adverse consequences as a result of their responses or bychoosing not to participate. Participants were considered toprovide consent by returning a completed survey.
2. Results
We received responses from all 310 participants (response
proportion = 100%), with 289 proving to be valid; of these,
223 (77.2%) lived in Fukushima Prefecture at the time of theGreat East Japan earthquake. To identify a suitable factor
structure for the FPAM, we conducted an exploratory factor
analysis (Table 5). The scree plot analysis indicated a twofactor solution, and the factor inter-correlation was 0.41;
factor 1 reflected “caring for a baby” and factor 2 reflected“giving birth to a baby.” In terms of the confirmatory factor
analysis, the model showed unacceptable measurement
2
properties (χ = 1067.7, df = 36, CFI = 0.83, TLI = 0.77,
RMSEA = 0.152, RMSEA 90% CI = 0.132–0.177, SRMR
= 0.114, AIC = 5430.3, BIC = 5500.0); consequently, we
chose to exclude from the factor analysis model itemswith low between-item correlation coefficients and itemswith reduced alpha coefficients. The “caring for a baby”
factor was represented by three items (“I look forward tocaring for a baby,” “I feel I will enjoy the baby,” and “I feelthat babies are not much fun to care for”), and the “giving
birth to a baby” factor was also represented by three items(“I am worried that the baby might have problems,” “I amconfident that I will have a normal childbirth,” and “I think
my labor and delivery will progress normally”). This newmodel demonstrated acceptable measurement properties(χ2 = 712.0, df = 15, CFI = 0.99, TLI = 0.98, RMSEA =0.058, RMSEA 90% CI = 0.006–0.100, SRMR = 0.039, AIC= 3508.0, BIC = 3555.7).
To identify the two most important FPAM items, we
calculated the alpha and correlation coefficients between
the factor scores and each item score. The FPAM items,
which reduced the alpha coefficients of each factor, were
excluded. The “caring for a baby” score was found to havethe highest correlation with “I look forward to caring for ababy” (ρ = 0.87), while the “giving birth to a baby” score
was most highly correlated with “I am confident that I will
have a normal childbirth” (ρ = 0.72). Therefore, thesewere the most important items associated with the factorsof “caring for a baby” and “giving birth to a baby.”
The alpha coefficients of “caring for a baby” and “giving
birth to a baby” were 0.86 and 0.65, respectively. The“caring for a baby” factor showed medium correlations
with the QOL (r = -0.23), self-efficacy (r = -0.24), andself-esteem (r = -0.21) scales, while the “giving birth to a

Table 5 Exploratory factor analysis of the empowerment scale

I look forward to caring for the baby.
（私は、赤ちゃんの世話をすることを楽しみにしています。）
I believe that I will enjoy caring for the baby.
2（私は、赤ちゃんとの生活を楽しむだろうと感じます。）
I feel that babies are not much fun to care for.（R）3（私は、赤ちゃんの世話は、そんなにおもしろい（楽しい）ものではないと感じています。）
I believe I can be a good mother.
4（私は、よい親になれると信じています。）
I am worried that the baby might have problems（R）
5（私は、赤ちゃんに何か問題があるかもしれないと気をもんでいます。）
I am confident that I will have a normal childbirth.
6（私は、大きな問題なく出産をする自信があります。）
I think my labor and delivery will progress normally.
7（私は、陣痛と分娩（出産）が正常に進行すると思っています。）
I worry about problems the baby might have.（R）8（私は、赤ちゃんが何らかの問題を持っているかもしれないと気になります。）
I have doubts about whether I will be a good mother.（R）9（私は、よい親になれるのか疑問があります。）
In general, I am able to live life the way I want to.
10（おおざっぱに言うと、私がやりたいように、自分の人生を生きることができる。）
Contribution ratio（%）
1

Factor Factor
Communality
2
1

M

SD

1.8

0.9

0.99

-0.14

0.88

1.8

0.8

0.95

-0.13

0.83

2.1

0.9

0.63

0.06

0.48

2.3

0.8

0.48

0.33

0.57

2.1

0.8

-0.14

0.67

0.51

2.3

0.8

0.16

0.63

0.60

2.3

0.7

0.22

0.50

0.52

2.4

0.9

-0.20

0.60

0.44

3.1

0.8

0.26

0.42

0.45

2.3

0.8

-0.00

0.13

0.10

36.89

16.63

（R）represents reversed wording. Thus, these items were reverse scored.

J. Natl. Inst. Public Health, 67 (1) : 201865

Shinya Ito et al., for the Pregnancy and Birth Survey Group of the Fukushima Health Management Survey
baby” factor showed medium correlations with the QOL (r= -0.17), self-efficacy (r = -0.18), self-esteem (r = -0.24),
and radiation-related risk perception measures (r = 0.19).
In relation to the “caring for a baby” factor, the standardized
partial regression coefficients of the WHO-5, RSES, and
GSES were -0.15, -0.07, and -0.17, respectively, and theadjusted R-squared value was 0.08. The standardized partial
regression coefficients of the “giving birth to a baby” factor
were -0.13, -0.18, and -.06, respectively, and the adjusted
R-squared value was 0.07. In terms of the most important
items reflecting these factors, the respective standardized
partial regression coefficients were -0.14 and -0.14 for the
WHO-5, -0.13 and -0.17 for the RSES, and -0.11 and -0.03
for the GSES. The adjusted R-squared values for the mostimportant items were 0.085 and 0.069, respectively.

IV．Discussion
The aims of this study were to: (1) provide an overview
of the FHMS Pregnancy and Birth Survey, (2) report on thefollow-up study of the FHMS Pregnancy and Birth Survey,and (3) report on a study of college womenʼs attitudes
towards future childbirth in Fukushima Prefecture.
In regard to the review of the FHMS Pregnancy andBirth Survey, the nuclear accident in Fukushima was foundto have not affected pregnancy outcomes, but to haveaffected maternal mental health, underlining the importanceof providing mental health support to mothers from the area
who have young children [18]. These results accord withthe report of Adams et al. in 2002 and 2011 [40,41], whofound that evacuee mothers in Kiev, Ukraine, who weredirectly affected by the Chernobyl nuclear accident, had
lower levels of psychological well-being and more negativerisk perception than control subjects, even at 11 [40] and19 [41] years after the event. These results suggest that
nuclear accidents cause mothers severe, long-lasting
psychological problems. It is therefore essential to provide
mental health support over long periods to mothers with
infants; such measures should be prioritized after all such
accidents.
In analyzing the follow-up to the 2011 FHMS survey,
we found that over 40% of mothers were worried about
experiencing a stigma as a consequence of their radiation
exposure; this anxiety was associated with maternalage, depressive symptoms, receiving antenatal care asscheduled, and post-quake medical history. Our findings onmothersʼ anxieties about stigmatization are similar to thoseof Bromet et al.; specifically, that the Chernobyl evacuees
felt that they were stigmatized when they resettled in other
cities [42]. The present study shows that providing support
for mothers who anxious about stigmatization continues to66

be a high priority in Fukushima.
For the third part of the study, we developed a new scale
to assess young womenʼs attitudes towards future childbirthand found that the scale had acceptable internal consistency
reliability, content validity, construct validity, and criterionrelated validity. The “caring for a baby” factor represented
participantsʼ expectations of caring for a future child, while“giving birth to a baby” reflected their confidence about
delivering a baby. We also extracted a two-item version of
the FPAM scale for practical purposes, and confirmed its
criterion-related validity.
The “giving birth to a baby” and the two-item versionof the “giving birth to a baby” tools were found to be
associated with “radiation-related risk perception.” Thisfinding is consistent with Satoʼs [43] report that college
students in Fukushima Prefecture worried that theirchildren may experience hereditary effects as a resultof their radiation exposure. Consequently, these results
indicate that young women in Fukushima who have been
evaluated as having a low risk of radiation exposure may
have increased confidence in regard to giving birth; thestudents who received low scores on the full and two-item
version of the FPAM scale demonstrated favorable resultsin terms of QOL, self-efficacy, and self-esteem. Our findings
are supported by previous studies, which have found an
association between self-stigma and self-efficacy and selfesteem [22,23]. It can consequently be suggested that thecontinuous provision of information on radiation-related
health effects, particularly targeting younger generations, isimperative to empower them as future mothers.
However, this study also had one major methodologicallimitation: it did not evaluate the reliability of the FPAM
scale. Consequently, to evaluate changes in the FPAM
scale over time (e.g., reflecting changes in participantsʼ
situations), future studies must assess this toolʼs test-retest
reliability.

V．Conclusion
The FHMS reported that radiation had no obvious effects
on childrenʼs health, but had significant effects on maternal
mental health, in part by generating anxieties about thestigma associated with radiation exposure. Young womenʼs
attitudes toward future pregnancy were found to be
associated with their radiation risk perception. Therefore,
providing mental health support to mothers with infants andadequate information on radiation health effects to younger
generations over long periods is important and should beprioritized, following any similar accidents, as well as thepresent accident.

J. Natl. Inst. Public Health, 67 (1) : 2018

Overview of the pregnancy and birth survey section of the Fukushima Health Management Survey

Conflicts of interest: None.
Authorsʼ Note
Members of the Pregnancy and Birth Survey Groupof the Fukushima Health Management Survey include
the following: Akira Ohtsuru, Shun Yasuda, and Yasuhisa
Nomura from Fukushima Medical University; Kenichi Hata
from the Fukushima Society of Obstetrics and Gynecology;
Kohta Suzuki from the University of Yamanashi; andAkihito Nakai from Nippon Medical School Tama Nagayama
Hospital. In addition, we want to thank Mie Sasaki,
Nobuhiro Konno, Osamu Sato, Yukihiko Kayama, and Kiyo
Kobayashi. The findings and conclusions of this article aresolely the responsibility of the authors and do not represent
the official views of the government of Fukushima
Prefecture.

Funding
The author(s) disclose receipt of the following financial
support for the research, authorship, and/or publication ofthis article: this survey was supported financially by the
National Health Fund for Children and Adults Affected by
the Nuclear Incident, and by the Grant-in-Aid for Young
Scientists (B) (Grant No.16K21256) of the Japan Ministry of
Education, Culture, Sports, Science, and Technology.

References[1] Bromet EJ. Emotional consequences of nuclear power
plant disasters. Health Phys. 2014;106:206-210.
[2] Yasumura S, Hosoya M, Yamashita S, Kamiya K, Abe
M, Akashi M, et al. Study protocol for the Fukushima
Health Management Survey. J Epidemiol. 2012;22:375383.
[3] Fukushima Health Management Survey Mental
Health and Lifestyle Survey (For Adults) 2011. http://
fukushima-mimamori.jp/foreign-languages/media/
mental/01_3.pdf (accessed 2017-11-15)[4] Fujimori K, Kyozuka H, Yasuda S, Goto A, Yasumura
S, Ota M, et al. Pregnancy and birth survey after theGreat East Japan Earthquake and Fukushima Daiichi
Nuclear Power Plant accident in Fukushima prefecture.
Fukushima J Med Sci. 2014;60:75-81.
[5] Goto A, Bromet EJ, Fujimori K. Immediate effects of the
Fukushima nuclear power plant disaster on depressive
symptoms among mothers with infants: a prefecturalwide cross-sectional study from the Fukushima HealthManagement Survey. BMC Psychiatry. 2015;15:59.

[6] Yoshida-Komiya H, Goto A, Yasumura S, Fujimori K,
Abe M. Immediate mental consequences of the greateast Japan earthquake and Fukushima nuclear power
plant accident on mothers experiencing miscarriage,
abor tion, and stillbir th: the Fukushima healthmanagement survey. Fukushima J Med Sci. 2015;61:6671.
[7] Ishii K, Goto A, Ota M, Yasumura S, Abe M, Fujimori K.
Factors associated with infant feeding methods after the
nuclear power plant accident in Fukushima: data fromthe Pregnancy and Birth Survey for the Fiscal Year 2011
Fukushima Health Management Survey. Matern Child
Health J. 2016;20:1704-1712.
[8] Kyozuka H, Yasuda S, Kawamura M, Nomura Y,
Fujimori K, Goto A, et al. Impact of the Great East Japan
Earthquake on feeding methods and newborn growthat 1 month postpartum: results from the Fukushima
Health Management Survey. Radiat Environ Biophys.
2016;55:139-146.
[9] Suzuki K, Goto A, Fujimori K. Effect of medical
institution change on gestational duration after
the Great East Japan Earthquake: The Fukushima
Health Management Survey. J Obstet Gynaecol Res.
2016;42:1704-1711.
[10] Goto A, Bromet EJ, Ota M, Ohtsuru A, Yasumura S,
Fujimori K. The Fukushima nuclear accident affectedmothers' depression but not maternal confidence. Asia
Pac J Public Health. 2017;29:139s-150s.
[11] Hayashi M, Fujimori K, Yasumura S, Nakai A. Impactof the Great East Japan Earthquake and Fukushima
Nuclear Power Plant Accident accident on assisted
reproductive technology in Fukushima Prefecture: The
Fukushima Health Management Survey. J Clin Med Res.
2017;9:776-781.
[12] Ishii K, Goto A, Ota M, Yasumura S, Fujimori K.
Pregnancy and birth survey of the Fukushima HealthManagement Survey. Asia Pac J Public Health.
2017;29:56s-62s.
[13] Ishii K, Goto A, Ota M, Yasumura S, Fujimori K.
Content and characteristics of mothers receiving
telephone counseling following the Fukushima Nuclear
Power Plant accident ― Data from the pregnancy andbirth survey of the Fukushima health management
survey, 2011―. Japanese Journal of Maternal Health.
2017;57:652-659 (in Japanese).
[14] Ito S, Goto A, Ishii K, Ota M, Yasumura S, Fujimori K.
Fukushima mothers' concerns and associated factors
after the Fukushima Nuclear Power Plant disaster. Asia
Pac J Public Health. 2017;29:151s-160s.
[15] Ministry of Health, Labour and Welfare. Vital Statistics.
2017. http://www.e-stat.go.jp/SG1/estat/NewListE.

J. Natl. Inst. Public Health, 67 (1) : 201867

Shinya Ito et al., for the Pregnancy and Birth Survey Group of the Fukushima Health Management Survey
do?tid=000001028897 (accessed 2017-11-19)[16] Inter national Clearinghouse for Bir th Defects
Surveillance and Research in Japan. Congenital
anomalies database. https://www.icbdsrj.jp/data.html(accessed 2017-11-15) (in Japanese)[17] Mishina A, Mishina H, Morita Y. Feasibility of twoquestion screening tool for maternal depressive
symptoms at well-child visits. Shonika Rinsho.
2011;64:2225-2229 (in Japanese).
[18] Mori T, Tsuchiya KJ, Matsumoto K, Suzuki K, MoriN, Takei N. Psychosocial risk factors for postpartum
depression and their relation to timing of onset: theHamamatsu Birth Cohort (HBC) study. J Affect Disord.
2011;135:341-346.
[19] Maeda M, Oe M. Mental health consequences and social
issues after the Fukushima disaster. Asia Pac J Public
Health. 2017;29:36s-46s.
[20] Save the Children. Fukushima families: children
and families affected by Fukushimaʼs nuclear crisis
share their concerns one year on. 2012. http://www.
savechildren.or.jp/jpnem/eng/wordpress/fukushima(accessed 2017-11-15)[21] Corrigan PW, Watson AC. The paradox of self-stigma
and mental illness. Clinical Psychology: Science andPractice. 2002;9:35-53.
[22] Livingston JD, Boyd JE. Correlates and consequences ofinternalized stigma for people living with mental illness:a systematic review and meta-analysis. Soc Sci Med.
2010;71:2150-2161.
[23] Corrigan PW, Watson AC, Barr L. The self-stigma of
mental illness: implications for self-esteem and selfefficacy. J Soc Clin Psychol. 2006;25:875-884.
[24] Crowne DP, Marlowe D. A new scale of social
desirability independent of psychopathology. J Consult
Clin Psychol. 1960;24:349-354.
[25] Kitamura T, Suzuki T. Japanese version of social
desirability scale. Japanese Journal of Social Psychiatry.
1986;9:173-180.
[26] Link BG. Understanding labeling effects in the areaof mental disorders: an assessment of the effects of
expectations of rejection. Am Sociol Rev. 1987;52:96112.
[27] Shimotsu S, Sakamoto S, Horikawa N, Sakano Y.
Reliability and validity of the Japanese version of the
Link's devaluation-discrimination scale. Japanese
Journal of Psychiatric TreatmentJpn J Psychiatr Treat.
2006;21:521-528.
[28] Tanabe Y, Hayashi K, Ideno Y. The Internalized Stigma
of Mental Illness (ISMI) scale: validation of the Japaneseversion. BMC Psychiatry. 2016;16:116.
[29] Ritsher JB, Otilingam PG, Grajales M. Internalized

68

stigma of mental illness: psychometric properties of a
new measure. Psychiatry Res. 2003;121:31-49.
[30] Esplen MJ, Stuckless N, Hunter J, Liede A, Metcalfe
K, Glendon G, et al. The BRCA Self-Concept Scale: a
new instrument to measure self-concept in BRCA1/2
mutation carriers. Psychooncology. 2009;18:1216-1229.
[31] Rogers ES, Chamberlin J, Ellison ML, Crean T. A
consumer-constructed scale to measure empowerment
among users of mental health services. Psychiatr Serv.
1997;48:1042-1047.
[32] Lederman R, Weis K. Psychosocial adaptation topregnancy: seven dimensions of maternal roledevelopment. New York: Springer; 2010.
[33] Okayama H, Takahashi M. Developing the Japaneseversion of the Prenatal Self-Evaluation Questionnaire.
Journal of Japanese Society of Psychosomatic Obstetrics
and Gynecology. 2002;7:55-63.
[34] Awata S, Bech P, Yoshida S, Hirai M, Suzuki S, Yamashita
M, et al. Reliability and validity of the Japanese versionof the World Health Organization-Five Well-Being
Index in the context of detecting depression in diabetic
patients. Psychiatry Clin Neurosci. 2007;61:112-119.
[35] Mimura C, Griffiths P. A Japanese version of the
Rosenberg Self-Esteem Scale: Translation andequivalence assessment. J Psychosom Res. 2007;62:589594.
[36] Rosenberg M. Society and the adolescent self-image.
Princeton (NJ): Princeton University Press; 1965.
[37] Sakano Y, Tohjoh M. The General Self-Efficacy Scale(GSES): scale development and validation. Japanese
Journal of Behavior Therapy. 1986;12:73-82.
[38] Yabe H, Suzuki Y, Mashiko H, et al. Psychologicaldistress after the Great East Japan Earthquake andFukushima Daiichi Nuclear Power Plant accident:
results of a mental health and lifestyle survey throughthe Fukushima Health Management Survey in FY2011
and FY2012. Fukushima J Med Sci. 2014;60:57-67.
[39] Kline RB. Principles and practice of structural equation
modeling, 2nd ed. New York: Guilford Press; 2005.
[40] Adams RE, Bromet EJ, Panina N, Golovakha E,
Goldgaber D, Gluzman S. Stress and well-being inmothers of young children 11 years after the Chornobyl
nuclear power plant accident. Psychol Med. 2002;32:143156.
[41] Adams RE, Guey LT, Gluzman SF, Bromet EJ.
Psychological well-being and risk perceptions ofmothers in Kyiv, Ukraine, 19 years after the Chornobyl
disaster. Int J Soc Psychiatry. 2011;57:637-645.
[42] Bromet EJ, Havenaar JM, Guey LT. A 25 year
retrospective review of the psychological consequencesof the Chernobyl accident. Clin Oncol (R Coll Radiol).

J. Natl. Inst. Public Health, 67 (1) : 2018

Overview of the pregnancy and birth survey section of the Fukushima Health Management Survey
2011;23:297-305.
[43] Sato O. The problems of radioactivity and the issues of
the nursery teacher training education: the considerationof the radioactivity anxiety of the students. Summary
Study Reports, Fukushima College. 2015;49:7-12.

J. Natl. Inst. Public Health, 67 (1) : 201869

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福島県県民健康調査「妊産婦に関する調査」の概説―放射線被ばくへの不安を抱える母親に焦点をあてて―
伊藤慎也 1)，後藤あや 2,3)，石井佳世子 3)，太田操 3,4)，安村誠司 1,3)，藤森敬也 3,5)，
放射線医学県民健康管理センター妊産婦調査室1)

福島県立医科大学医学部公衆衛生学講座

2)

福島県立医科大学総合科学教育研究センター3)

福島県立医科大学放射線医学県民健康管理センター4)

福島県立医科大学看護学部母性看護学・助産学部門
福島県立医科大学医学部産科婦人科学講座

5)

抄録
目的：本研究の目的は（1）福島県県民健康調査「妊産婦に関する調査」をレビューすること，（2）
放射線被ばくに伴うスティグマによる不安を抱える母親の割合，およびスティグマによる不安の関連
要因を明らかにすること，（3）新しく“Fukushima Future Parents Attitude Measure” (FPAM尺度)を作成して，将来の妊娠出産に対する態度を明らかにすることの 3 点である．
方法：（1）乳児および母親の健康状態を明らかにするために，福島県県民健康調査「妊産婦に関する調査」データを使用した11論文をレビューした．（2）放射線被ばくに伴うスティグマによる不安を分析するために，2011年のベースライン調査および2015年のフォローアップ調査のデータを使用した．
フォローアップ研究では，母親の主観的健康観，抑うつ症状，育児の自信，放射線被ばくに伴うスティグマによる不安等を評価した．
（3）福島県の女子大学の学生310名を対象に質問紙調査を行った．
結果：（1）福島県県民健康調査「妊産婦に関する調査」データの分析によると，福島原子力発電所
事故は妊娠に対して有意な影響を与えていないが，母親の精神的健康に有意な影響を与えていた．
（2）
974名（41.2％）の母親がスティグマに伴う不安を感じていた．特に，母親の年齢，抑うつ症状の有無，予定通りの妊婦健診の受診，震災後の新たな病気・状態の有無が有意にスティグマに伴う不安と関連していた．（3）探索的および確認的因子分析を行った結果，“caring for a baby”（ 3 項目）と“giving
birth to a baby” (3項目)の 2 因子が抽出された．これらの 2 因子は生活の質，自己効力感，自尊感情と相関関係を示し，“giving birth to a baby”因子は放射線のリスク認知とも相関関係を示した．
結論：福島県県民健康調査「妊産婦に関する調査」の論文レビューより，小さい子供を持つ母親への精神的健康支援が重要と考えられる．2015年のフォローアップ研究より，母親の40％以上が放射線被ばくに伴うスティグマによる不安を示していることが示された．また，新しく作成したFPAM尺度によると，若い女性の将来の妊娠出産に対する態度は，放射線のリスク認知と関連していることが示唆された．
キーワード：福島県県民健康調査，スティグマ，福島原子力発電所事故，放射線，FPAM尺度

70

J. Natl. Inst. Public Health, 67 (1) : 2018