Association between omega-3 fatty acid supplementation and lower risk of preterm delivery: a systematic review and meta-analysis

Pre-pregnancy overweight or obesity moderates the association between prenatal maternal depressive symptoms and infant cord blood omega-3 levels

BACKGROUND

Empirical evidence has demonstrated associations between pre-pregnancy obesity and perinatal maternal depressive symptoms. Omega-3 is an essential fatty acid derived from dietary sources that is critical for fetal brain development. Pre-pregnancy obesity is associated with higher omega-3 intake, but a weaker association between dietary intake and respective maternal and cord blood omega-3 levels. Further, lower intake of omega-3 during pregnancy has been linked to higher depressive symptoms. Yet, prior studies have not examined the interactive effects of pre-pregnancy overweight or obesity (OWOB) and prenatal maternal mental health symptoms on infant cord blood omega-3 levels.

METHODS

Participants included 394 maternal-infant dyads from the NIH Environmental influences on Child Health Outcomes (ECHO) - Safe Passage Study in South Dakota. A pre-pregnancy body mass index (BMI) > 25 was used to dichotomize participants as OWOB (54%) vs. non-OWOB (46%). Prenatal maternal depressive symptoms were measured using the Edinburgh Postnatal Depression Scale (EPDS) and prenatal maternal anxiety symptoms were measured using the State-Trait Anxiety Inventory (STAI). We implemented linear regression models to examine the interaction term between pre-pregnancy BMI category and prenatal maternal mental health symptoms on cord blood omega-3 levels. Secondary analyses were stratified by pre-pregnancy BMI category.

RESULTS

We observed a significant interaction between pre-pregnancy BMI category and prenatal maternal depressive symptoms with cord blood omega-3 (F(4,379) = 6.21, p < .0001, adj. R2 = 0.05). Stratified models revealed an association between prenatal maternal depressive symptoms with lower cord blood omega-3 levels only among individuals with pre-pregnancy OWOB (β = -0.06, 95% CI = -0.11, -0.02; F (2,208) = 4.00, p < .05, adj R2 = 0.03). No associations were observed among non-OWOB participants.

CONCLUSIONS

Findings suggest maternal-placental transfer of omega-3 may represent one pathway by which maternal metabolic and mental health impacts infant development.

The Intake of Omega-3 Fatty Acids, the Omega-3 Index in Pregnant Women, and Their Correlations with Gestational Length and Newborn Birth Weight

BACKGROUND

During pregnancy, the demand for omega-3 fatty acids, notably docosahexaenoic acid (DHA), escalates for both maternal and foetal health. Insufficient levels can lead to complications and can affect foetal development. This study investigated omega-3 status and its relation to dietary intake in pregnant Latvian women, along with its impact on gestational duration and newborn birth weight.

METHODS

The study comprised 250 pregnant and postpartum women with a mean age of 31.6 ± 4.8 years. Nutrition and omega-3 supplementation data were collected through a questionnaire covering 199 food items and 12 supplements. Fatty acids in erythrocyte membrane phospholipids were analysed via gas chromatography with flame ionization detection.

RESULTS

The median omega-3 fatty acid intake, including eicosapentaenoic acid (EPA) and DHA from diet and supplements, was 0.370 g/day, which is deemed sufficient. However, the median weekly fish intake (126.0 g) and daily nut/seed intake (7.4 g) were insufficient. The median omega-3 supplement intake was 1.0 g/day. No correlation between omega-3 supplement intake and the omega-3 index was observed. There was a weak correlation between the DHA intake from fish and the omega-3 index (r = 0.126, p = 0.047), while a significant correlation between the total EPA and DHA intake from various sources and the omega-3 index was noted (r = 0.163, p = 0.01). Most women (61.6%) had an omega-3 index < 4%, while 34.8% had an index between 4 and 8%, and only 3.6% had an index > 8%. Notably, significant differences in EPA levels and the omega-3 index were found among respondents with differing infant birth weights (p < 0.05).

CONCLUSIONS

The omega-3 intake during pregnancy adheres to the established guidelines, although fish consumption remains insufficient. A preconception evaluation of the omega-3 index is advocated to optimize prenatal intake. The indications suggest potential correlations between EPA levels, the omega-3 index, and infant birth weight.

A modular systematic review of antenatal interventions to address undernutrition during pregnancy in the prevention of low birth weight

BACKGROUND

Poor nutrition during pregnancy can lead to adverse birth outcomes including low birth weight (LBW).

OBJECTIVE

This modular systematic review aimed to provide evidence for the effects of seven antenatal nutritional interventions on the risks of LBW, preterm birth (PTB), small-for-gestational-age (SGA) and stillbirth (SB).

METHODS

We searched MEDLINE, Embase, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials and CINAHL Complete between April and June 2020, with a further update in September 2022 (Embase only). We included randomized controlled trials (RCTs) and reviews of RCTs to estimate the effect sizes of the selected interventions on the four birth outcomes.

RESULTS

Evidence suggests that balanced protein and energy (BPE) supplementation for pregnant women with undernutrition can reduce the risk of LBW, SGA and SB. Evidence from low and lower middle-income countries (MIC) suggests that multiple micronutrient (MMN) supplementation can reduce the risk of LBW and SGA in comparison with iron or iron and folic acid supplementation and lipid-based nutrient supplements (LNS) with any quantity of energy can reduce the risk of LBW in comparison with MMN supplementation. Evidence from high and upper MIC suggests that supplementation with omega-3 fatty acids (O3FA) can reduce the risk and supplementation with high-dose calcium might possibly reduce the risk of LBW and PTB. Antenatal dietary education programs might possibly reduce the risk of LBW in comparison with standard-of-care. No RCTs were identified for monitoring weight gain followed by interventions to support weight gain in women who are underweight.

CONCLUSIONS

Provision of BPE, MMN and LNS to pregnant women in populations with undernutrition can reduce the risk of LBW and related outcomes. The benefits of O3FA and calcium supplementation to this population require further investigation. Targeting interventions to pregnant women who are not gaining weight has not been tested with RCTs.

Maternal Plasma RNA in First Trimester Nullipara for the Prediction of Spontaneous Preterm Birth ≤ 32 Weeks: Validation Study

The first-trimester prediction of spontaneous preterm birth (sPTB) has been elusive, and current screening is heavily dependent on obstetric history. However, nullipara lack a relevant history and are at higher risk for spontaneous (s)PTB ≤ 32 weeks compared to multipara. No available objective first-trimester screening test has proven a fair predictor of sPTB ≤ 32 weeks. We questioned whether a panel of maternal plasma cell-free (PCF) RNAs (PSME2, NAMPT, APOA1, APOA4, and Hsa-Let-7g) previously validated at 16-20 weeks for the prediction of sPTB ≤ 32 weeks might be useful in first-trimester nullipara. Sixty (60) nulliparous women (40 with sPTB ≤ 32 weeks) who were free of comorbidities were randomly selected from the King's College Fetal Medicine Research Institute biobank. Total PCF RNA was extracted and the expression of panel RNAs was quantitated by qRT-PCR. The analysis employed, primarily, multiple regression with the main outcome being the prediction of subsequent sPTB ≤ 32 weeks. The test performance was judged by the area under the curve (AUC) using a single threshold cut point with observed detection rates (DRs) at three fixed false positive rates (FPR). The mean gestation was 12.9 ± 0.5 weeks (range 12.0-14.1 weeks). Two RNAs were differentially expressed in women destined for sPTB ≤ 32 weeks: APOA1 (p < 0.001) and PSME2 (p = 0.05). APOA1 testing at 11-14 weeks predicted sPTB ≤ 32 weeks with fair to good accuracy. The best predictive model generated an AUC of 0.79 (95% CI 0.66-0.91) with observed DRs of 41%, 61%, and 79% for FPRs of 10%, 20%, and 30%, including crown-rump length, maternal weight, race, tobacco use, and age.

Vegan nutrition: a preliminary guide for health professionals

Since the beginning of the 21st century, interest in vegan diets has been rapidly increasing in most countries. Misconceptions about vegan diets are widespread among the general population and health professionals. Vegan diets can be health-promoting and may offer certain important advantages compared to typical Western (and other mainstream) eating patterns. However, adequate dietary sources/supplements of nutrients of focus specific to vegan diets should be identified and communicated. Without supplements/fortified foods, severe vitamin B12 deficiency may occur. Other potential nutrients of focus are calcium, vitamin D, iodine, omega-3 fatty acids, iron, zinc, selenium, vitamin A, and protein. Ensuring adequate nutrient status is particularly important during pregnancy, lactation, infancy, and childhood. Health professionals are often expected to be able to provide advice on the topic of vegan nutrition, but a precise and practical vegan nutrition guide for health professionals is lacking. Consequently, it is important and urgent to provide such a set of dietary recommendations. It is the aim of this article to provide vegan nutrition guidelines, based on current evidence, which can easily be communicated to vegan patients/clients, with the goal of ensuring adequate nutrient status in vegans.

Effects of Dietary Patterns during Pregnancy on Preterm Birth: A Birth Cohort Study in Shanghai

The objective of this study was to analyse representative dietary patterns during pregnancy in Shanghai and explore the effects of dietary patterns during pregnancy on preterm birth. Data were derived from the ‘Iodine Status in Pregnancy and Offspring Health Cohort’ (ISPOHC) study. Multistage, stratified random sampling was used to select survey participants from 16 districts in Shanghai, which were divided into five sampling areas; 40–70 pregnant women were selected from each area. A total of 4361 pregnant women and their offspring were involved in the study. The male-to-female ratio of the babies was 1.04:1, and the incidence of single preterm birth was 4.2%. Three dietary patterns were extracted by factor analysis: a ‘Vegetarian Pattern’, an ‘Animal Food Pattern’ (AFP), and a ‘Dairy and Egg Pattern’. These patterns explained 40.513% of the variance in dietary intake. Binary logistic regression, which was used to analyse the association between birth outcomes and scores measuring maternal dietary patterns, found only the AFP was a significant risk factor for preterm birth. Higher AFP scores were positively associated with preterm birth (Q2 vs. Q1 OR = 1.487, 95% CI: 1.002–2.207; Q3 vs. Q1 OR = 1.885, 95% CI: 1.291–2.754). After adjusting for other potential contributors, a higher AFP score was still a significant risk factor for preterm birth (Q2 vs. Q1 OR = 1.470, 95% CI: 0.990–2.183; Q3 vs. Q1 OR = 1.899, 95% CI: 1.299–2.776). The incidence of preterm birth was 4.2%. A higher score of AFP was significantly associated with a higher risk of preterm birth. The animal food intake of pregnant women should be reasonably consumed during pregnancy.