Oily fish consumption and n-3 fatty acid status in late pregnancy: the Southampton Women's Survey

Abstract

Fatty acids have an important role in fetal growth and development, and requirements for long-chain PUFA, particularly the n-3 fatty acid (FA) DHA, are increased in pregnancy (1) . Oily fish is one of the richest sources of n-3 FA, including DHA. Current levels of oily fish and n-3 FA consumption in non-pregnant women in the UK are low compared with recommendations (2) . However, little is known about variations in n-3 FA intake and dietary influences on n-3 FA status in pregnant women in the UK (2) . The aim of this study was to describe variations in oily fish intake, and associations with plasma n-3 FA concentrations in women taking part in the Southampton Women's Survey (SWS). At around 34 weeks gestation, venous blood samples were taken, and the n-3 FA content of plasma phosphatidylcholine (PC) determined using GC. Diet was assessed using an administered food frequency questionnaire that recorded the frequency of consumption of 'oily fish' in the three preceding months. Complete n-3 FA data were available for 1765 (89 %) women who delivered before the end of 2003.The median frequency of consumption of oily fish was once a fortnight; 36 % of the women were consuming oily fish once a week or more. There were strong correlations between oily fish consumption and the percentages of EPA, DHA and total n-3 FA in plasma PC (r = 0.264, r = 0.398 and r = 0.378 respectively, all P < 0.0001) (see Fig.

Fish Consumption during Pregnancy in Relation to National Guidance in England in a Mixed-Methods Study: The PEAR Study

“…Indeed, there are few data on the consumption of fish in pregnancy, but in accordance with our findings they have shown intakes below those recommended by SACN on which the NHS guidance is based. These include the ALSPAC study in 1991–1992 (40% ate white fish at least once per week, and only 23% ate oily fish 1–3 times per week, with 18% never or rarely eating any white fish, and 43% never or rarely eating any oily fish [ 30 ]), the Southampton Women’s Study in 1998–2007 (only 36% ate oily fish once a week or more) [ 15 ] and the CARE Study in 2003–2006 (oily fish intakes in pregnant women who were consumers was 101 g/week (<1 portion)) [ 14 ]. For all adults, the National Diet and Nutrition Survey (NDNS) found mean intakes of oily fish of 56 g per week (<<1 portion) in 2016–2019 [ 16 ].…”

“…Little is known, however, about the effects of the existing guidance on fish consumption on the frequency of the consumption of fish by pregnant women in England. Indeed, there is little current information on the frequency of consumption of fish in pregnancy in England, but there is evidence that consumption is below the lower limit of two portions of fish a week in total (including at least one portion of oily fish) recommended for the general population and for pregnancy by SACN [ 10 , 14 , 15 , 16 ]. Such information could provide an evidence base to inform the future development of the content of the guidance and its dissemination in order to maximise its usability and beneficial impact.…”

A review of guidance on fish consumption in pregnancy: is it fit for purpose?

“…More specifically, in the UK (where the recommended intake is for at least 2 portions fish/week with at least 1 portion oily fish/week; Table 2), women aged 19–64 years participating in the National Diet and Nutrition Survey (NDNS) from 2008 to 2012 ate a mean of 22 g fish/d (about 1 portion/week) including just 8 g oily fish/d (about 0·3 portion/week) ( 57 ) ; mean consumption in pregnant women enrolled in ALSPAC was 235 g/week (about 1·5 portions/week) but 12 % ate no fish at all ( 37 ) ; in the Southampton Women’s Study, total fish consumption was 1·8 times/week and oily fish consumption was about 0·5 times/week ( 55 , 58 ) . Findings in the USA are similar: women of childbearing age in the National Health and Nutrition Examination Surveys (NHANES) ate a median of 81 g/week (about 0·5 portion/week) and 23 % reported not eating any fish ( 59 , 60 ) ; mean fish intake in pregnant women was 1·5 portions/week and 14 % never ate any fish.…”