Listeria monocytogenes and diet during pregnancy; balancing nutrient intake adequacy v. adverse pregnancy outcomes

Abstract

Objective: To evaluate the impact of adherence to public health recommendations on Listeria monocytogenes food safety to limit exposure to potential food sources on micronutrient intakes of pregnant women and whether more frequent consumption of 'high-risk' foods increases risk for adverse pregnancy outcomes. Design: A cohort study in women assessing Listeria exposure from an FFQ based on consumption of potential Listeria-containing food sources, the Listeria Food Exposure Score (LFES). Pregnancy status was defined as pregnant, trying to conceive, had a baby within the previous 12 months, or other. Nutrient intakes were compared with Nutrient Reference Values and self-reported pregnancy outcome history three years later. Setting: Australia. Subjects: Women aged 25-30 years (n 7486) participating in the Australian Longitudinal Study on Women's Health. Results: There were weak positive correlations (r 5 0?13-0?37, P , 0?001) between LFES and all nutrients, with fibre, folate, Fe and vitamin E intakes consistently below the Nutrient Reference Values in every quintile of LFES. Women in the highest quintile of LFES reported 19 % more miscarriages (rate ratio 5 1?19; 95 % CI 1?02, 1?38) than those in the lowest quintile, after adjusting for important confounding factors. Conclusions: More frequent consumption of foods potentially containing L. monocytogenes is associated with higher nutrient intakes, but an increased risk of miscarriage. L. monocytogenes pregnancy recommendations require review and should include the list of 'risky' food items in addition to low-risk alternatives that would adequately replace nutrient intakes which may be reduced through avoidance strategies.

A decrease in diet quality occurs during pregnancy in overweight and obese women which is maintained post-partum

“…7,14,39 This may be related to specific food avoidances in pregnancy with an increased aversion to meat and fish (27% and 4% of women) previously reported, 40 and an increased proportion of pregnant women avoiding raw meat, fish, shellfish and milk cheese and organ meat compared with nonpregnant women. 41 Recent Australian data has also reported pregnant women with a lower intake of Listera-containing foods have lower micronutrient intakes, 42 suggesting greater avoidance of foods from the milk, meat and unsaturated oils components may be related to a greater avoidance of potential sources of Listeria monocytogenes. We also observed an increase in the proportional intake of calories from SoFAAS consistent with previous reports of an increase in a high-energy diet score during pregnancy but no change in a prudent diet score 14 and lower alcohol intake in pregnant compared with non-pregnant women.…”

Diet during pregnancy: Women's knowledge of and adherence to food safety guidelines

“…It is critical that information provided to pregnant women about what foods to avoid during pregnancy also provide information about how to ensure adequate nutrition during pregnancy. For example, a national study of Australian childbearing women found that avoiding foods identified as higher risk of Listeria contamination was associated with poorer diet quality and nutrient intakes …”

High-protein diets during pregnancy: healthful or harmful for offspring?

“…Even within developed countries there is considerable variation in maternal protein intake, with younger mothers of lower socioeconomic status more likely to have lower protein intakes (3). In addition, the perceived risk of food-borne listeria infection leads some pregnant women to severely restrict important sources of high-quality protein, with adverse implications on diet quality, nutrient intakes, and pregnancy outcomes (22,23). The challenge is to balance benefit and risk to achieve better maternal and offspring health outcomes.…”