A qualitative study of fish consumption during pregnancy1–3
Arienne Bloomingdale, Lauren B Guthrie, Sarah Price, Robert O Wright, Deborah Platek, Jess Haines, and Emily Oken
Background: Many pregnant women in the United States do not
consume enough docosahexaenoic acid (DHA)—an essential nutri-
ent found in fish. Apparently conflicting findings that fish consump-
tion is beneficial for the developing fetus, yet potentially toxic
because of mercury contamination, have created uncertainty about
the appropriate fish-consumption advice to provide to pregnant women.
Objective: Our objective was to determine knowledge, behaviors,
and received advice regarding fish consumption among pregnant
women who are infrequent consumers of fish.
Design: In 2009–2010 we conducted 5 focus groups with 22 preg-
nant women from the Boston area who ate ,2 fish servings/wk. We
analyzed transcripts by using immersion-crystallization.
Results: Many women knew that fish might contain mercury, a neu-
rotoxin, and had received advice to limit fish intake. Fewer women
knew that fish contains DHA or what the function of DHA is. None
of the women had received advice to eat fish, and most had not
received information about which fish types contain more DHA or
less mercury. Because of advice to limit fish intake, as well as a lack
of information about which fish types they should be eating, many
of the women said that they would rather avoid fish than possibly
harm themselves or their infants. The participants thought that
a physician’s advice to eat fish and a readily available reference
regarding which fish are safe to consume during pregnancy would
likely have encouraged them to eat more fish.
Conclusion: Pregnant women might be willing to eat more fish if
this were advised by their obstetricians or if they had an accessible
reference regarding which types are safe.
Am J Clin Nutr 2010;
Fish and other seafood are healthful foods that are the primary
dietary source for elongated omega-3 (n–3) polyunsaturated fatty
during pregnancy, particularly docosahexaenoic acid (DHA), is
essential for optimal fetal neurodevelopment and may also
protect against other adverse perinatal and longer-term outcomes
(2). In the past few years, expert panels have released consensus
guidelinesfor DHA intakeduring pregnancy(2). Onlyaboutone-
quarter of pregnant women in the United States are eating the
amount of DHA recommended for optimal maternal and child
However, fish may also be contaminated with methylmercury,
a demonstrated neurotoxin to which the fetal brain is particularly
sensitive (3). Overall, ’10% of women of childbearing age in
the United States have higher than recommended mercury
concentrations (4). The US Food and Drug Administration and
Environmental Protection Agency have issued warnings rec-
ommending that pregnant women limit their fish consumption to
avoid excess mercury exposure (5, 6). Pregnant women con-
sumed less fish after these guidelines were disseminated (7).
These apparently conflicting findings—that fish consumption
is healthy for the developing fetus yet simultaneously potentially
toxic—have created considerable uncertainty as to the appro-
priate fish consumption advice to provide pregnant women.
Classically, simple public health messages, such as “Don’t smoke”
are the most effective. However, in this circumstance a nuanced
approach may be indicated, because women should both avoid fish
likely to be high inmercury and seek out fish that islow in mercury
and high in DHA.
Qualitative research is an important first step to developing an
effective public health message (8). Little work has been done to
understand what pregnant women know about the risks and
benefits of fish consumption during pregnancy, from where they
get their information to what underlies their fish-consumption
habits, especially among women who are infrequent fish con-
sumers. We conducted a series of focus groups to better un-
derstand pregnant women’s knowledge of the health effects of fish
consumption during pregnancy, to learn what fish consumption
advice they had received and from where, to determine whether
and for what reasons they made any changes in fish consumption
to fish intake.
SUBJECTS AND METHODS
Study design and population
From November 2009 to March 2010, we conducted 5 focus
groups with a total of 22 participants. We recruited women by
1From the Department of Population Medicine, Harvard Medical School
and the Harvard Pilgrim Health Care Institute (AB, LBG, SP, JH, and EO);
the Channing Laboratory, Brigham and Women’s Hospital, Boston, MA
(ROW); the Children’s Hospital Boston, Boston, MA (ROW); and the De-
partment of Obstetrics, Harvard Vanguard Medical Associates, Boston, MA
2Supported by grant R01 ES016314, Pilot Project funding from the
HSPH-NIEHS Center for Environmental Health (P01 ES000002), and the
Harvard Pilgrim Health Care Institute.
3Address correspondence to E Oken, Department of Population Medi-
cine, Harvard Medical School and the Harvard Pilgrim Health Care Institute,
133 Brookline Avenue, Boston, MA 02215. E-mail: emily_oken@
Received July 2, 2010. Accepted for publication August 19, 2010.
First published online September 15, 2010; doi: 10.3945/ajcn.2010.30070.
Am J Clin Nutr 2010;92:1234–40. Printed in USA. ? 2010 American Society for Nutrition
using postings displayed at Boston-area obstetrics clinics,
advertisements in a local newspaper, in online classified adver-
tisements, and at a local parenting listserv. The posting identified
the project as a study of “diet during pregnancy,” but did not
interested women to contact us.
The research assistant interviewed responders via telephone to
determine eligibility and to collect demographic information. To
be eligible for participation, a woman had to be ?18 y of age and
currently pregnant. Because we were interested in targeting
women with low fish and DHA intakes, we included only
women who reported consuming fish ,2 times/wk but who had
no contraindications to fish consumption such as allergy or self-
restrictions, such as vegetarian diet. So that potential partic-
ipants were not aware of the study’s particular focus on fish, the
screening instrument also included questions on other compo-
nents of diet, including intake of fruit and vegetables, nuts, and
meat. Of the 47 interested women, 11 eligible women were
unable to attend our scheduled group meeting times, and we
excluded another 14 ineligible women (9 who consumed fish ?2
times/wk and 5 who would not consume fish at all). The Harvard
Pilgrim Health Care Human Subjects Committee reviewed and
approved all study protocols. All participants provided written
Structure of focus groups
We developed the moderator’s script based on the goals of
ascertaining what pregnant women knew about the benefits and
risks of fish consumption, from where they had heard advice
regarding fish consumption, what their fish consumption
behaviors were, and whether they had changed their intake offish
during pregnancy. Study co-investigators and a convenience
sample of local pregnant women reviewed the focus group script
to ensure that it was clear and addressed all target topics. An
experienced focus group moderator who was not a study in-
vestigator led the group discussions. Before the first group, the
moderator provided feedback and suggested edits to the script.
After each focus group, the study investigators met together with
the moderator to further refine the script for clarity.
To allow a discussion of general diet before focusing on fish,
the moderator began the focus groups with discussion topics
regarding what participants had heard about healthy pregnancy
dietary choices and about which foods should be avoided or
encouraged. The moderator then shifted the discussion to focus
eating fish, mercury, and omega-3 fatty acids. Participants were
asked from what sources they had heard information about fish
consumption during pregnancy and whether and how their fish
consumption had changed since they became pregnant. We were
particularly interested in understanding factors influencing the
amount and types of fish consumed, such as cost, availability,
cravings or nausea impeded or increased their consumption of
fish during pregnancy. Sample questions appear in Table 1.
Throughout the sessions, the moderator encouraged participants
to speak until all views were expressed and often probed for
further clarification. The moderator did not attempt to reach
group consensus on any topics and did not attempt to quanti-
tatively determine the number of responses to each question.
We held all focus groups in the evening, and provided dinner.
The discussions lasted 1.5–2 h, including 0.5 h for dinner. At the
end of each focus group discussion, we gave each participant
a pamphlet that details the current US Food and Drug Admin-
istration guidelines for fish consumption during pregnancy (9).
We also gave a $25 gift card to all participants.
We audio-recorded the group discussions, and the research
assistant—who had been trained in note-taking—took detailed
research assistant then transcribed the focus group discussions
using her notes and the audiotapes.
After we completed the focus groups, we held a series of
meetings during which we developed and then refined a series of
general themes encompassing all of the group discussions. Two
investigators (EO and AB) assigned each participant comment to
one or more themes. After the 2 investigators independently
coded the transcript from one focus group, we reconvened as
a group to assess our level of concordance regarding which
to consensus about any comments for which we had assigned
divergent themes. Once we felt confident that we shared an
understanding of what each theme was meant to capture, we
assigned these themes to the comments contained in the re-
maining 4 focus group transcripts. For the few comments on
which we could not reach consensus, another investigator (JH)
provided the final assignment.
Oncewehad assigned one or more themes to each comment,we
analyzed the transcripts by using the immersion-crystallization
approach (10). This approach involves prolonged immersion into
the text, which allows for an intuitive crystallization of emerging
themes. From repeated readings of the data, we developed
Discussion topics addressed in focus groups and sample questions from the
Topics Sample questions from moderator script
Knowledge Have you heard of any types of fish that might be safer
or healthier to eat during pregnancy?
Why are these fish types likely to be healthy?
Have you heard of any types of fish that might be less
safe or healthy to eat during pregnancy?
Why are these fish types less healthy?
What have you heard about the health effects of eating
Where did you hear this information? Is this a source
Before you became pregnant, what types of fish did you
eat? How often?
How have you changed how often you eat fish since
How have you changed the types of fish that you eat
since becoming pregnant?
What are some factors that influence how much or which
types of fish you eat now?
QUALITATIVE STUDY OF FISH CONSUMPTION
subthemes within our 5 predefined general themes and identified
additional themes that we had not classified a priori.
Of the 22 participants, 13 were white, 5 were black, 2 were
Hispanic, and 2 were of other race-ethnicities. Ten participants
were pregnant for the first time, and 18 participants had completed
was 21 wk, and the participants ranged in age from 19 to 35 y.
We identified 7 major themes in our analysis (Table 2). The 5
predetermined themes were the participants’ knowledge of the
health effects of fish, advice they had received, fish intake be-
haviors, and barriers and facilitators to fish intake. The 2 emer-
gent themes were the women’s emotions regarding fish intake
and diet philosophies that influenced fish intake. We summarized
these themes and the subthemes within them and provide rep-
resentative quotes in the sections below and in Table 2.
The women’s knowledge generally fell into 3 subthemes: the
health effects of fish and its components (mercury, omega-3 fatty
acids/DHA), which fish types were more or less healthful and
why, and the amounts and types of fish they believed they could
safely eat during pregnancy. Many (10 of 22) women mentioned
that fish can contain mercury. Most (16 of 22) had a sense that
mercury is “dangerous” and “can affect neurological de-
velopment.” Some did not feel that they had in-depth knowledge
of its effects: “I think it’s just supposed to be toxic. That’s about
as far as I got with it.” Three women mentioned a possible
connection between mercury exposure and autism. A few also
mentioned bacteria, parasites, or contaminants from the canning
process as reasons to avoid fish. None mentioned polychlorinated
biphenyls as a contaminant associated with fish.
few exceptions, most could not name any of the other 3 types that
the US Federal Mercury Advisory has recommended that preg-
nant women should avoid, although none mentioned those fish
as types they would eat. Others knew that mackerel, bluefish, and
fish that are larger, “high on the food chain,” “deep sea fish,” or
“predatory” were more likely to contain mercury. When asked
which fish are higher in mercury, some women named types that
do not tend to contain high levels of mercury, including catfish,
shrimp, shellfish, “fattier fish,” and “bottom feeders.”
likedtoeat,butwereconfusedaboutwhich typeoftunathey could
eat: “There’s like chunk light, and all the different kinds. I forget
which one you’re supposed to eat and which ones you’re not.”
Shellfish was another source of confusion. During the groups
several women questioned: “what’s the deal with shellfish, you
guys?” or “and I can never remember about shellfish—is it you’re
supposed to eat it, or you’re not?” Other women’s viewpoints
ranged from “we’re not supposed to eat shellfish,” to “really? Not
shellfish? I thought it was okay as long as they were cooked.”
Many women “couldn’t remember” what omega-3 fatty acids
and DHA do, although some mothers (8 of 22) recalled that they
are supposed to have a “positive health effect.” A subset of these
women (5 of 22) knew that DHA is “supposed to help with brain
functioning,” and a few mentioned other potential health benefits
including “your cholesterol”and “good for your eyes.Goodfor. ..
just everything.” One woman commented that she “didn’t know
DHA is an omega-3 fatty acid.”
Severalwomenidentifiedsalmonas afishthatis generally safe
and high in omega-3 fatty acids. Other types that women iden-
tified as safe or healthful fish to eat during pregnancy included
trout, tilapia, herring, red snapper, scallops, lobster, sardines, and
fish that are “fattier,” “smaller” or “lighter, flakier.” However,
to eat during pregnancy, and, of the others, most had a hard time
naming more than one or a few healthful fish types: “I know that
there are more, but I couldn’t give you a list.”
Many of the women could not identify a particular frequency
of fish consumption that they should be or were targeting. If the
women did report a specific guideline for safe fish intake during
pregnancy, most commonly they thought it was once aweek. One
mentioned “5 oz a week of fish that could have mercury in it.”
Several mentioned a limit for intake of tuna fish in particular: in
some cases one serving per week, whereas others believed they
could not eat any tuna.
Some of the women had received some information from their
obstetrician or midwife regarding which types of fish to avoid
during pregnancy, usually in the form of a handout. However, most
did not have any conversation about fish intake with their obstetric
provider, and some felt that they did not receive an adequate ex-
planation about why they should be avoiding these types: “It’s a lot
know that you don’t have to do, but you don’t really know why.”
Most women followed their physician’s advice to limit fish
intake: “You know, my doctor doesn’t recommend it, so don’t
a month—that’s what my doctor and I negotiated.” Another
recalled “I went to the Bahamas a couple months ago. And it’s,
like, a big grouper fishing area and that would have been what I
was eating probably 2 or 3 times when I was there. But I ne-
gotiated one piece of grouper.”
In addition, very few of the women were told which types of
fishtheycould eat: “I haven’t heard which are the healthier fish to
eat. I’ve heard which are the ones to avoid, but not to eat.” None
received advice during their pregnancy that they should try to eat
fish, but they might have followed such advice: “If they told me it
If they’re sure about what they’re saying and, like, the studies
have shown that it was ok, I would do it.”
Beyond fish, many of the women had no discussions with their
obstetric care providers about diet: “My doctor leaves mewith an
me about the vitamins, about the baby, everything else but not
about my eating.” However, women would find such discussions
Which, right now it’s making me wonder why aren’t we talking
more about it? Because it would be good information to receive.”
Most of the women did not pay much heed to advice that they
received from friends or acquaintances: “everybody has their
BLOOMINGDALE ET AL
Summary of results from the analysis of 5 focus groups with 22 pregnant women from the Boston area1
Themes Major subthemes Representative comments from focus group participants
1. KnowledgeFish contain mercury—a toxin that is harmful to the brain. “Developmental delays…um, just something you want to
steer away from.”
“Omega 3 fatty acids. I don’t know what they do, but I know
they’re supposed to be good for us.”
“I heard once a week somewhere. And I don’t know if it was
in a handout that my midwife gave me, or if it was in
a book, but I definitely have heard the once a week thing
“I think really just more information about which fish is
good, would…probably help me. Like I’m kind of
feeling like now I should figure out which fish are good
fish and then we can start eating those again.”
“I used to eat canned tuna, and then I read that you shouldn’t
eat tuna, but I didn’t know it was the more fatty one, so I
just didn’t eat it at all.”
can have that.”
“Theyjustsaystayawayfromit,Idon’treallyhave a reason,
just you know, it’s not safe for the baby.”
“My take away from the conversations I’ve had is like, ‘you
should avoid fish because of the high mercury content’
and there wasn’t really the distinction made between
good fish vs. bad fish. I mean, some, but, you know, the
overall takeaway message with fish was ‘avoid it.’ So had
there been more discussion about like, ‘here are the good
fish you can eat’ and, you know, the positive aspects, I
might be eating more fish.”
“I haven’t eaten fish at all during these entire 36 wk and no
one’s really pushed me or told me, ‘you should probably
increase your fish intake’ ”
“I love sushi so that was a huge one for me and that just went
out the window.”
“My husband and I were trying to get pregnant, so I
“I just don’t remember which of the 10,000 fish I can have
and I can’t. So I think I just lean toward the safe ones,
because I’ve remembered that I can have them.”
“I often wish I could eat more than one serving a week…just
because I like it and for the protein.
“I’ve always thought of fish as being expensive. Where with
chicken I leave for a couple days in the fridge, fish I
would want to make sure I use right away.”
“For a while, I was feeling really nauseous so I wasn’t
cooking anything because opening the fridge was
problematic ’cause it smelled bad. So… the fish would
not be an appealing smell in the fridge, so it’s not
“If my husband is willing to cook it, we’ll have it, but
otherwise we’re not having it.”
“I don’t like fish that well, but yeah, I would be more
comfortable in the grocery store if I had this little card
that I could pull it out and say ‘oh, look and I shouldn’t
have it,’ or ‘hey, it’s on this list and I haven’t had it
a couple weeks, so I should get it.’”
“I wouldn’t say ‘no’ to eating it if I knew it was beneficial to
me and the baby.”
Fish contain DHA and omega-3 fatty acids. These are
healthful, but many women did not know why.
Fish consumption once a week, or less often, is
recommended for pregnancy.
Women do not know much about which fish types are
healthful to eat.
Many women liked tuna fish but were confused about
whether they could continue to eat it and, if so, which
types to eat.
Many women were also confused about whether they could
Some received written information about the risks of fish
intake, but few had a discussion with their obstetrician.
Women were not told which fish types are safer to eat.
Women received no encouragement to eat fish during
3. Behaviors Sushi was a main source of fish intake before pregnancy that
was eliminated during pregnancy.
Many women reduced or eliminated their fish intake with
Some women tried to get more DHA via supplements or
Women could not remember which fish types were better to
eat during pregnancy.
Advice to avoid fish led many women to eat less fish than
they otherwise would have.
Some women perceived fish to be costly and something that
needed to be eaten very fresh.
Some women experienced pregnancy-related aversions to
5. FacilitatorsWomen were more likely to eat fish if their families also ate
A portable list would help women eat more fish.
If their obstetricians advised them to eat fish, they would do
QUALITATIVE STUDY OF FISH CONSUMPTION
opinion on what to eat when pregnant.” None had learned any-
thing about risks or benefits of fish intake from prenatal classes.
Whereas many of the women had read about dietary advice on the
deal of trust in these sources unless they were perceived to bevery
reliable. In general many felt that not enough information was
readily available: “I just don’t see it out there a lot,for itto stick in
pregnancy and this is what is not good for you.’ I just don’t see
enough information about this subject.”
Eleven of the women reported that they ate sushi before
pregnancy and had stopped during pregnancy, which had the
result of reducing their fish intake. Others had specifically
changed their intake of particular fish types in response to fish
consumption advisories: “The tuna steaks, or the big, thick steaks
of swordfish, I know you have to be careful . . . so I’ve just cut
those guys out completely now.” Others reduced intake of fish
types not included in advisories, even though they liked the fish
and were eating it only occasionally: “I like haddock and tilapia
but I don’t eat it too often, probably once a month I would say.
You know, when I was eating it. But now, I’ve really abstained
from it.” Some reduced their fish intake in anticipation of
pregnancy: “[before pregnancy, I was eating fish] probably once
to twice a week. But my husband and I were trying to get preg-
nant, so I stopped.”
Intake of tuna fish in particular decreased from before preg-
nancy, in part because women were no longer eating tuna sushi.
Also, several women limited or reduced their intake of canned
tuna fish: “I used to add tuna on top of a salad at the salad bar. But
I don’t do that anymore.”
Onlyonewoman, anutritionistherself,mentioned thatshewas
interested in increasing her intake of fish during pregnancy,
though she had not actually done so. Some sought out DHA-
enriched eggs or DHA-containing prenatal vitamins. A few were
taking fish oil. However, most had not changed their diet to
increase the intake of omega-3 fatty acids or DHA.
Lack of knowledge regarding which fish types are safer to eat
during pregnancy emerged as a common barrier to fish con-
sumption. “Oh, the other one is you can have some canned tuna
but not other canned tunas, so I just didn’t do anything. I’m like,
‘I’m not eating canned tuna. That’s done’.” Another woman
similarly said: “Since I’m not gonna take the time to figure out
which one is safest to eat, I’m like ‘ok, I’m not gonna stress
myself out with trying to find out what’s the best.’” Some of the
women were limiting their overall fish intake because they were
told to eat a certain amount: “I often wish I could eat more than
one serving a week, because I often find myself wanting tuna
salad a lot, just because I like it and for the protein.”
In some cases, the women’s inability to remember which fish
typesare more orless healthfulled them notto eat fishat all. “But
the dietician that I saw, I honestly can’t remember what she said
about good fish and bad fish . . . so I’ve just been avoiding fish
based on that conversation.” In other cases, the women re-
membered a few types of fish that are safer to eat, and limited
their intake only to those types: “I feel like it’s hard to remember
which fish are safe when you’re out. So it’s nice to be able to be
like ‘salmon I know is always safe’.”
Whereas some women felt that pregnancy-related nausea or
aversions made them less likely to eat fish (“It’s mostly the smell
too. That’s what turns me off.”), about the same number of
women reported an increased taste for fish since becoming
pregnant. A few felt that they did not want to eat anything that
they had not tried before: “I don’t think it’s the time to be trying
new stuff, during pregnancy.”
Many felt that fish was expensive: “I think a lot of it comes
down to the cost. I mean, we haven’t had salmon in months just
because of the cost;” “sometimes you want fish but like it goes
back to the cost. Sometimes the fish is too expensive where you
can just get a couple of chicken breasts and call it a day;” “part of
it also is that it’s more expensive than turkey, so you know . . .
I would put money aside to buy it.” Other barriers to fish intake
included the women’s preference to eat only very fresh fish, the
perception that fish can be difficult to prepare, or the fact that
TABLE 2 (Continued)
Themes Major subthemes Representative comments from focus group participants
6. Emotions It can be scary to eat fish. “I try to, ofcourse, keep away from the seafood, just because
that’s what scares me the most.”
“You know, it’s a double-edged sword though because I’ve
also read that if you don’t eat enough fish you don’t get
enough omega vitamins and so to, like manage this
balance between don’t get enough mercury, but eat
enough fish and it can get really confusing.”
“I know high, high, high levels can certainly do damage, I
don’t know if I believe that low levels can, so, but its just
like it’s not worth the anxiety to thinking that there could
be some effect of the mercury.”
“But I do think about like, I don’t know, there are some
communities like around the world where people eat
a whole lot of fish. Some of these rules, I just put them in
the context of history and it just doesn’t feel right and it
feels kind of arbitrary sometimes.”
Fish consumption messages are conflicting and confusing.
7. Diet philosophies It is better to be safe than sorry.
Women elsewhere eat fish and are fine.
1DHA, docosahexaenoic acid.
BLOOMINGDALE ET AL
other family members, especially children, may not like fish:
“with my husband being vegetarian and my daughter, I know
she’s not gonna eat it, so then it’s kind of pointless . . . that’s
a factor for me. No one to share it with.”
Facilitators to fish consumption included having a husband or
partner who liked or prepared fish, or family traditions that in-
cluded fish: “My parents always did lobster for New Years.”
Many women thought that if they were told how much or
which types of fish they could safely eat, they would be more
likely to eat more fish: “If I was told the type of fish to buy, if it
was recommended that this is the kind of fish that pregnant
women should eat, I would . . . buy that fish.” A number of
participants would have liked a list they could keep with them: “I
can never remember—that’s the problem. I feel like you need to
that awallet card in particular would bevery helpful: “I feel like I
need a wallet size card—I’m not kidding, that has, like, one side
with fish to avoid and the other with fish that’s safe, good to eat
when you’re pregnant. So that like when I’m out shopping, or if
I’m out eating and I can’t remember if the fish is ok, I’ll have
something to consult with. It sounds a little ridiculous, but I
almost wish I got that at my OB’s office.”
As women discussed the fish consumption messages they had
heard, many expressed frustration and confusion because “it’s
a double-edged sword:” “the mercury levels are too high, yeah.
Which is concerning, because, I don’t know . . . it’s conflicting
again. You hear that fish is so good for you, yet on the other hand
it’s filled with mercury and we need to look out for that . . . but yet
we’re supposed to eat it at least twice a week.” Another was
similarly bewildered: “that’s the main thing I find confusing, so
like salmon, that’s a pretty big fish, so maybe we shouldn’t eat it,
but it’s also higher in good fat, so don’t eat it, but no, do eat it.”
Many of the women used negative or fearful language when
talking about fish intake. If they chose to eat a fish that might be
higher in mercury they were being “bad”: “I had scallops the
other day and I wasn’t sure whether I was being bad or not.” One
commented that fish carries a “stigma.” The fish consumption
messages they had seen ranged from “a little bit stressful” to
making them feel afraid: “there’s been a lot of literature at the
hospitals about eating fish and things like that and that’s just
something that I stay away from, just because of the scares about
about omega-3s and yet we’re so scared to eat any fishand I think
that’s all people talk about instead of focusing on ‘here are the
fish you can’t eat’ and they tend to be the ones that you don’t
consume, besides swordfish, the ones on the list are not very
common. So I think it’s just kind of ironic that we’re so scared of
it, but yet that’s one of the things that, you know, nutrient-wise is
definitely quite beneficial during the pregnancy period.”
When it came to mercury exposure, many of the women felt
that it was better to be safe than sorry: “why take a chance?”
Some representative comments include: “When I think about
mercury, I just wanna stay away;” “It’s not worth it . . . I can get
by without it.” Several expressed that avoiding all fish seemed to
be safer than making a wrong choice: “I just always feel like I
never know what the right thing is to do and I don’t want to do
something wrong and, you know, have something bad happen.”
Even when they heard messages that contradicted their judg-
ment, some followed the cautionary principal: “I would have
thought you kind of shouldeat itmore than that, but I don’t, I eat it
any sense to me. So I’m now staying away from shrimp.”
However,otherswere morephlegmatic in their approach tothe
messages they had received: “We’re not supposed to eat shellfish.
Which . . . I have eaten lobster twice and shrimp on various
occasions. So I think, I don’t know—I like to live by the old rule
of thumb that—everything in moderation.” Several mentioned
that they followed their own instincts rather than a strict dietary
guideline: “I take the once a week rule or whatever it is with
a grain of salt. And go morewith what I know about my body and
like my experience with fish oil has informed my fish consump-
that women elsewhere are less mindful of their fish intake and
appear to do fine: “I figure women in developing countries have
babies all the time thatare totally healthy and if I eat like a couple
pieces of sushi here and there, it’ll probably be fine.” “My friend
who grew up in Japan she’s like ‘you know, people in Japan they
eat sushi when they’re pregnant.’ So it’s another of those things
where one culture does it and another doesn’t. So who do you go
Among pregnant women who were infrequent fish consumers,
most knew that fish may contain mercury, a neurotoxin, and had
received some advice to limit or avoid intake of fish. However,
fewer knew that fish contains DHA or what beneficial health
effects DHA may have. None reported having received advice to
eat fishasawayofincreasing their DHA intake,andmost hadnot
received any information about which fish types are safer to eat.
Advice to limit intake of fish, as well as their inability to recall or
have a ready source of information about which fish types they
should be eating, led manywomen to eat less fish than they might
otherwise be eating. Faced with a lack of available information,
or their babies to harm.
Several studies have reported on the characteristics of women
who eat more or less fish, based on surveys or dietary ques-
tionnaires. Women who are older, are better educated, have
higher income, or live in coastal areas tend to eat more fish and
elongated omega-3 fatty acids (11, 12). Only a few qualitative
studies have been reported. Troxell et al (13) have reported on
work they performed among pregnant women enrolled in the
Special Supplemental Program for Women, Infants, and Children
(WIC). They used focus groups to develop and evaluate an in-
tervention to increase dietary DHA intake among pregnant
women by promoting consumption of salmon, sardines, tuna, and
DHA-enriched eggs. These investigators did not provide detailed
results from the focus groups, but did report that a primary
motivator for the women to change their behavior was benefit to
the infant.Wedidnotfindany qualitativestudies amongpregnant
QUALITATIVE STUDY OF FISH CONSUMPTION
women that included discussions of both health risks of con-
taminants as well as benefits of DHA within fish.
Other studies, mostly conducted outside of the United States,
have focused on factors influencing fish consumption by adults
and families. As in our study, important factors influencing fish
consumption among adults in the general population are taste
preferences, price, and convenience (14, 15). Among mothers of
in the current study,including that thepreferences of other family
members and perceptions that fish is expensive might be barriers
to fish intake (16). However, unlike among the pregnant women
we studied, concerns about contaminants did not influence
consumption, and arguments for the beneficial health effects of
fish were not likely to overcome barriers to intake. These dif-
ferences may have been because public health advice regarding
fish consumption differs between Australia and the United States,
because the health risks of mercury and benefits of DHA are
particularly salient during pregnancy or because it can be more
difficult to change the dietary habits of a child compared with
Olsen (17) has proposed that, among adults, almost all con-
sumers agree that fish is healthy; therefore, the perceived health
valueoffish does notexplainmuch variation in fish consumption.
aware of the content and effect of harmful substances than of
nutrientsin fish,and many didnot know thatfishcontains omega-
3 fatty acids or what health effects these nutrient may have (18).
This finding is similar to our results, ie, that women were more
aware of and influenced by the potential health risks of con-
taminants in fish rather than the potential nutritional benefits.
The present study had several strengths, including discussions
of both potential health risks and benefits associated with fish
consumption. We included women of diverse race-ethnicity. Al-
though the study population was small, results were similar across
all 5 focus groups, and we did not discover any new themes after
our initial analysis of the first group. We limited participation to
women who were consuming ,2 fish servings/wk; results may
have differed between women who are more frequent fish con-
sumers. Also, because all participants lived in the greater Boston
area, the results may not be generalizable to women living in
other areas of the United States, to women with less education,
or to different ethnic groups than those included in the present
In conclusion, many pregnant women have received the mes-
sage that fish may contain mercury—a contaminant potentially
harmful to the fetus. However, women are less aware of the health
to be low in mercury and higher in DHA. Pregnant women who
infrequently consume fish might bewilling to eat more fish if they
received advice to eat some fish from their obstetrician or other
sources and if they had a clear, readily accessible source of in-
formation regarding which fish types are safe to eat during
pregnancy. The results from this study might be useful for public
health officials or others planning educational interventions re-
garding fish consumption during pregnancy.
from Matthew Gillman, Christina Kamins, and Barbara Kaufman; and the
substantive comments we received from Julia MacDonald, Ashley O’Brien,
and Elsie Taveras.
The authors’ responsibilities were as follows—EO: responsible for the
study design, data collection, data analysis, writing of the manuscript, and
obtaining funding; AB: contributed to the data collection, data analysis,
and writing of the manuscript; LBG: contributed to the study design and data
the study design and to obtaining funding. All authors approved the final ver-
sion of the manuscript. None of the authors had a conflict of interest to report.
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