Assessment of DHA on reducing early preterm birth: the ADORE randomized controlled trial protocol

Maternal Urinary Fluoride Levels of a Large Pregnancy Cohort in the United States: Findings from the ADORE Study

BACKGROUND

Emerging evidence has suggested negative associations between maternal urinary fluoride adjusted for specific gravity (MUFsg) and offspring intelligence quotient (IQ). Two prior studies report the MUFsg of pregnant women in the US, both in California, and more information is needed on population levels of MUFsg.

OBJECTIVES

The primary objective was to measure MUFsg in a large pregnancy cohort of women recruited from health departments and academic hospitals in Ohio and Kansas. A secondary objective was to compare associations between water fluoridation level and estimated fluoride intake from tap water and MUFsg.

METHODS

Pregnant women (n = 965 ) from the ADORE (Assessment of DHA on Reducing Early Preterm Birth) cohort provided a urine sample and dietary assessment at enrollment between 14 and 20 wk gestation. MUFsg was measured by fluoride-sensitive electrode and corrected for specific gravity. Water fluoridation levels were obtained for public water systems (PWS), matched to participant residence and multiplied by their tap water intake from dietary assessment. The association between MUFsg and water fluoridation level was estimated using a generalized linear model with gamma distribution and log link.

RESULTS

MUFsg (median: 1.0 mg / L ; Q1, Q3: 0.6, 1.5) was correlated with PWS fluoridation (r s = 0.30 ; p < 0.01 ) and self-reported tap water consumption (r s = 0.29 ; p < 0.01 ). For 87% of the cohort, MUFsg was above the 0.45 mg / L safety benchmark for pregnancy proposed in a previous study. Similarly, 76.7% lived in areas with PWS fluoridation ≥ 0.7 mg / L . The median MUFsg (1.0 mg / L ; Q1, Q3: 0.7, 1.5) of those living in areas with a PWS fluoridation level ≥ 0.7 mg / L was higher than the median MUFsg (0.8 mg / L ; Q1, Q3: 0.5, 1.2) of women living in areas with PWS fluoridation < 0.7 mg / L (p < 0.01 ).

DISCUSSION

MUFsg in this population of midwestern US women exceeds the safety benchmark for pregnancy. While we cannot account for all sources of fluoride, MUFsg was correlated to PWS fluoridation. Because so many exceeded the safety benchmark for MUFsg, there is a need for MUFsg evaluation in other US regions, especially where the PWS fluoridation exceeds US Department of Health and Human Services recommendations (≥ 0.7 mg / L ). https://doi.org/10.1289/EHP14711.

Docosahexaenoic acid (DHA) Supplementation During Pregnancy Reduces the Risk of Preterm Birth in Threatened Preterm Labor. The Multicenter Randomized Controlled Trial

Background

Threatened preterm labor is a common reason for hospital admission, and DHA supplementation may lower the risk of preterm labor.

Objective

To compare the rates of premature birth between individuals with threatened preterm labor who received DHA and those who did not.

Methods

In this multi-center randomized controlled trial, the sample size was calculated to be 60 participants. Pregnant individuals who experienced threatened preterm labor at 24 to 34 weeks gestation were given either 1000 milligrams of DHA daily or no DHA supplement. The criteria for inclusion consisted of singleton pregnancies that had been diagnosed with threatened preterm labor, with no cervical change present. DHA supplementation was initiated when threatened preterm labor was diagnosed and continued until 37 weeks of gestation or until delivery, whichever occurred first. The main outcome was to compare the rates of premature births between the two groups. Moreover, we intended to evaluate the side effects of the DHA supplement along with the outcomes for neonates.

Results

Sixty-one pregnant individuals were enrolled and randomly assigned to two groups. Group 1 consisted of 30 participants, each receiving a daily intake of 1,000 milligrams of DHA supplement. Group 2, comprising 31 individuals, did not receive any supplemental DHA. The rate of preterm birth was 23.33% (7/30) and 25.81% (8/31) for the participant group receiving DHA and not receiving DHA, respectively, with a p-value of 0.82. The rate of low-birth-weight neonates was 13.33% (4/30) and 19.35% (6/31) for the participant group receiving DHA and not receiving DHA, respectively, with a p-value of 0.73. The overall results did not show any statistically significant differences. In addition, the rates of cesarean sections, peripartum infections, early postpartum hemorrhage, and NICU admissions did not show significant differences between the two groups.

Conclusion

Taking DHA supplements after a diagnosis of threatened preterm pregnancy does not decrease the actual rates of early or late preterm births. To reduce the risk of premature birth, DHA should be taken from the beginning of pregnancy, with a recommendation to start in the first trimester. This should ideally start in the second trimester, no later than around 20 weeks of gestation, and should continue until childbirth or approximately 37 weeks of gestation.

Clinical Trial Registration

https://register.clinicaltrials.gov/.

Clinical Trials

gov; ID: NCT06302023.

Enhancing DHA supplementation adherence: A Bayesian approach with finite mixture models and irregular interim schedules in adaptive trial designs

Docosahexaenoic acid (DHA) supplementation has proven beneficial in reducing preterm births. However, the challenge lies in addressing nonadherence to prescribed supplementation regimens-a hurdle that significantly impacts clinical trial outcomes. Conventional methods of adherence estimation, such as pill counts and questionnaires, usually fall short when estimating adherence within a specific dosage group. Thus, we propose a Bayesian finite mixture model to estimate adherence among women with low baseline red blood cell phospholipid DHA levels (<6%) receiving higher DHA doses. In our model, adherence is defined as the proportion of participants classified into one of the two distinct components in a normal mixture distribution. Subsequently, based on the estimands from the adherence model, we introduce a novel Bayesian adaptive trial design. Unlike conventional adaptive trials that employ regularly spaced interim schedules, the novelty of our proposed trial design lies in its adaptability to adherence percentages across the treatment arm through irregular interims. The irregular interims in the proposed trial are based on the effect size estimation informed by the finite mixture model. In summary, this study presents innovative methods for leveraging the capabilities of Bayesian finite mixture models in adherence analysis and the design of adaptive clinical trials.

DHA supplementation for early preterm birth prevention: An application of Bayesian finite mixture models to adaptive clinical trial design optimization

BACKGROUND

Early preterm birth (ePTB) - born before 34 weeks of gestation - poses a significant public health challenge. Two randomized trials indicated an ePTB reduction among pregnant women receiving high-dose docosahexaenoic acid (DHA) supplementation. One of them is Assessment of DHA on Reducing Early Preterm Birth (ADORE). A survey employed in its secondary analysis identified women with low DHA levels, revealing that they derived greater benefits from high-dose DHA supplementation. This survey's inclusion in future trials can provide critical insights for informing clinical practices.

OBJECTIVE

To optimize a Phase III trial design, ADORE Precision, aiming at assessing DHA supplement (200 vs. 1000 mg/day) on reducing ePTB among pregnant women with a low baseline DHA.

METHODS

We propose a Bayesian Hybrid Response Adaptive Randomization (RAR) Design utilizing a finite mixture model to characterize gestational age at birth. Subsequently, a dichotomized ePTB outcome is used to inform trial design using RAR. Simulation studies were conducted to compare a Fixed Design, an Adaptive Design with early stopping, an ADORE-like Adaptive RAR Design, and two new Hybrid Designs with different hyperpriors.

DISCUSSION

Simulation reveals several advantages of the RAR designs, such as higher allocation to the more promising dose and a trial duration reduction. The proposed Hybrid RAR Designs addresses the statistical power drop observed in Adaptive RAR. The new design model shows robustness to hyperprior choices. We recommend Hybrid RAR Design 1 for ADORE Precision, anticipating that it will yield precise determinations, which is crucial for advancing our understanding in this field.

Docosahexaenoic Acid (DHA) and Eicosapentaenoic Acid (EPA)-Should They Be Mandatory Supplements in Pregnancy?

Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are essential fatty acids for the human body. Seafood and microalgae are the most important sources of omega-3 fatty acids. Supplementation with 200 mg/day of DHA during pregnancy and breastfeeding has been suggested for women and infants in countries with low seafood consumption. Maternal concentration of DHA and EPA was associated with concentration in cord blood and breast milk. High concentrations of DHA and EPA were identified at the level of retinal photoreceptors and neuronal cell membranes. It was observed that supplementation with DHA and EPA during pregnancy had beneficial effects on the neurological development of the fetus and infant by improving language, memory, attention, and hand coordination, affecting sleep patterns, and improving visual acuity. Beneficial effects on the development of the infant were also associated with the maternal intake of omega-3 fatty acids during breastfeeding. Supplementation with DHA and EPA may reduce the risk of preterm birth but also of preeclampsia in low-risk pregnancies. Women of childbearing age should have an intake of 250 mg/day of DHA + EPA from their diet or supplements. To reduce the risk of premature birth, pregnant women must additionally receive at least 100-200 mg of DHA every day. It is recommended that supplementation with omega-3 fatty acids starts before 20 weeks of pregnancy. Beneficial effects on the mother have been identified, such as the reduction of postpartum depression symptoms, the decrease of cardiovascular risk, and the anti-inflammatory role.

The Effect of Prenatal Docosahexaenoic Acid Supplementation on Offspring Fat Mass and Distribution at 24 Months Old

Background

Excessive gestational weight gain (GWG) is related to increased offspring fat accrual, and increased fat mass (FM) is related to obesity development. Prenatal DHA supplementation has been linked to lower levels of offspring FM; however, conflicting data exist.

Objectives

This study aimed to determine if there is a protective effect of prenatal DHA supplementation on offspring fat accrual and adipose tissue deposition at 24 mo in offspring born to females who gain excessive weight compared with nonexcessive weight during pregnancy. We also explored if the effect of DHA dose on FM differed by offspring sex.

Methods

Infants born to females who participated in the Assessment of DHA on Reducing Early Preterm Birth randomized controlled trial (ADORE) were recruited. In ADORE, females were randomly assigned to either a high or low prenatal DHA supplement. Offspring body composition and adipose tissue distribution were measured using dual-energy x-ray absorptiometry (DXA). GWG was categorized as excessive or not excessive based on clinical guidelines.

Results

For total FM, there was a significant main effect for the DHA dose (P = 0.03); however, the dose by GWG status was nonsignificant (P = 0.44). Therefore, a higher prenatal DHA dose was related to greater offspring FM (622.9 g greater) and unrelated to GWG status. When investigating a DHA dose by sex effect, a significant main effect for DHA dose (P = 0.01) was detected for central FM. However, no interaction was detected (P = 0.98), meaning that both boys and girls had greater central FM if their mother was assigned to the higher DHA dose.

Conclusions

Greater prenatal DHA supplementation was associated with greater offspring FM and adipose tissue distribution at 24 mo. It will be important to understand if these effects persist into childhood.This trial was registered at clinicaltrials.gov as NCT03310983.

Differential DHA and EPA Levels in Women with Preterm and Term Births: A Tertiary Hospital Study in Indonesia

BACKGROUND Preterm birth is one of the main causes of neonatal death worldwide. One strategy focused on preventing preterm birth is the administration of long chain polyunsaturated fatty acids (LCPUFAs) during pregnancy. Omega-3 LCPUFAs, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are essential in metabolic and physiological processes during embryonic and fetal development. This study aimed to compare DHA and EPA levels in 44 women with preterm births and 44 women with term births at a tertiary hospital in West Java Province, Indonesia, between November 2022 and March 2023. MATERIAL AND METHODS A total of 88 patients in this study consisted of 44 patients with term births (≥37 gestational weeks) and 44 patients with preterm births (<37 gestational weeks) at a tertiary hospital in West Java Province, Indonesia. This observational, cross-sectional study was conducted from November 2022 to March 2023. Using the enzyme-linked immunosorbent assay test, maternal DHA and EPA levels were investigated. IBM SPSS 24.0 was used to statistically measure outcomes. RESULTS Average maternal DHA and EPA levels in patients with preterm births were significantly lower than those in term births. Preterm labor risk was further increased by DHA levels of ≤5.70 µg/mL (OR=441.00, P=0.000) and EPA levels ≤3971.54 µg/mL (OR=441.00, P=0.000). CONCLUSIONS Since the average maternal DHA and EPA levels were significantly lower in patients with preterm births, adequate intake of omega-3 LCPUFA in early pregnancy and consistency with existing nutritional guidelines was associated with a lower risk of preterm delivery for pregnant women.

DHA, nutrient intake, and maternal characteristics as predictors of pregnancy outcomes in a randomised clinical trial of DHA supplementation

PURPOSE

To investigate the relationships among docosahexaenoic acid (DHA) intake, nutrient intake, and maternal characteristics on pregnancy outcomes in a phase III randomised clinical trial designed to determine the effect of a DHA dose of 1000 mg/day compared to 200 mg/day on early preterm birth (<34 weeks gestation).

METHODS

A secondary aim of the phase III randomised trial was to explore the relationships among pregnancy outcomes (maternal red blood cell phospholipid (RBC-PL) DHA at delivery, preterm birth, gestational age at delivery, labor type, birth anthropometric measures, low birth weight, gestational diabetes, pre-eclampsia, and admission to a neonatal intensive care unit) in participants (n = 1100). We used Bayesian multiple imputation and linear and logistic regression models to conduct an analysis of five general classes of predictor variables collected during the trial: a) DHA intake, b) nutrient intake from food and supplements, c) environmental exposure to tobacco and alcohol, d) maternal demographics, and e) maternal medical history.

RESULTS

DHA supplementation lowered the risk of preterm birth and NICU admission, and increased gestation and birth weight as observed in the primary analysis. Higher maternal RBC-PL-DHA at delivery was associated with DHA supplementation and formal education of a bachelor's degree or higher. DHA supplementation and maternal age were associated with a higher risk of gestational diabetes. Total vitamin A intake was associated with longer gestation, while fructose and intake of the long chain omega-6 fatty acid, arachidonic acid, were associated with shorter gestation. Risk of preterm birth was associated with a history of low birth weight, preterm birth, pre-eclampsia, and NICU admission.

CONCLUSION

Bayesian models provide a comprehensive approach to relationships among DHA intake, nutrient intake, maternal characteristics, and pregnancy outcomes. We observed previously unreported relationships between gestation duration and fructose, vitamin A, and arachidonic acid that could be the basis for future research.

TRIAL REGISTRATION NUMBER AND DATE

ClinicalTrials.gov (NCT02626299); December 10, 2015.

Reference Range of Plasma Fatty Acids in North Indian Pregnant Population

Reference values for Fatty Acids (FAs) are not well defined in the Indian population. Therefore, it is critical to establish FAs reference range for the healthy non-pregnant and pregnant Indian population. The present multi-centric, and cross-sectional study determines the 95% reference interval for FAs in an apparently pregnant Indian population and compare it to the healthy non-pregnant women. Physicians identified 164 reference individuals as healthy (56 non-pregnant and 108 pregnant) at various government and private hospitals of northern India. The 95th and 97.5th percentile reference limits were used to estimate the 95 percentile of the reference distribution. The reference ranges observed for Alpha-linolenic acid (0.29-0.42%; 0.36-0.58%), Docosahexaenoic-acid (3.38-4.23%; 3.8-4.55%), Eicosapentaenoic-acid (1.24-1.76%; 1.09-1.62%), Docosapentaenoic-acid-3 (0.61-0.69%; 0.65-0.76%), Linoleic-acid (18.44-20.75%; 19.51-21.88%), gamma-linolenic-acid (0.24-0.35%; 0.32-0.42%), Eicosatrienoic-acid (0.26-0.32%; 0.34-0.39%), Arachidonic-acid (9.29-11.02%; 10.02-11.56%), Docosatetraenoic-acid (0.62-0.89%; 0.79-1.09%), Docosapentaenoic-acid-6 (0.23-0.31%; 0.33-0.41%), Eicosatrienoic-acid (1.17-1.41%; 1.43-1.74%), Eicosenoic-acid (0.28-0.38%; 0.37-0.49%), Nervonic-acid (1.39-1.69%; 1.41-1.74%), Palmitoleic-acid (1.17-1.58%; 2-2.66%), Oleic-acid (19.8-22.26%; 19.68-22.94%), Myristic-acid (1.16-1.68%; 0.82-1.3%), Palmitic-acid (20.05-21.8%; 20.7-22.43%), Stearic-acid (11.34-12.56%; 10.29-11.02%), Arachidic-acid (0.17-0.2%; 0.18-0.23%), Lignoceric-acid (0.81-1.08%; 0.77-1.08%), trans-palmitoleic-acid (0.22-0.29%; 0.26-0.37%), trans-oleic-acid (0.55-0.72%; 0.68-0.84%), trans-linoleic-acid (0.38-0.54%; 0.42-0.59%) respectively for non-pregnant and pregnant women. Furthermore, total FAs were significantly (p ≤ 0:05) higher in women aged 31-45 years than in women aged 16-30 years. whereas, there was no significant change in total FAs profile based on omega-supplementation, diet category, preterm-birth history, and gestation period. Thus, the current study provides information about an individual who is deficient in FAs and the dose required to increase FA concentrations in the body.

Growth and adiposity in newborns study (GAINS): The influence of prenatal DHA supplementation protocol

BACKGROUND

Obesity and central fat mass (FM) accrual drive disease development and are related to greater morbidity and mortality. Excessive gestational weight gain (GWG) increases fetal fat accretion resulting in greater offspring FM across the lifespan. Studies associate greater maternal docosahexaenoic acid (DHA) levels with lower offspring FM and lower visceral adipose tissue during childhood, however, most U.S. pregnant women do not consume an adequate amount of DHA. We will determine if prenatal DHA supplementation is protective for body composition changes during infancy and toddlerhood in offspring exposed to excessive GWG.

METHODS AND DESIGN

Infants born to women who participated in the Assessment of DHA on Reducing Early Preterm Birth randomized controlled trial (ADORE; NCT02626299) will be invited to participate. Women were randomized to either a high 1000 mg or low 200 mg daily prenatal DHA supplement starting in the first trimester of pregnancy. Offspring body composition and adipose tissue distribution will be measured at 2 weeks, 6 months, 12 months, and 24 months using dual energy x-ray absorptiometry. Maternal GWG will be categorized as excessive or not excessive based on clinical guidelines.

DISCUSSION

Effective strategies to prevent obesity development are lacking. Exposures during the prenatal period are important in the establishment of the offspring phenotype. However, it is largely unknown which exposures can be successfully targeted to have a meaningful impact. This study will determine if prenatal DHA supplementation modifies the relationship between maternal weight gain and offspring FM and FM distribution at 24 months of age.

ETHICS AND DISSEMINATION

The University of Kansas Medical Center Institutional Review Board (IRB) approved the study protocol (STUDY00140895). The results of the trial will be disseminated at conferences and in peer reviewed publications.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT03310983.

Iodine Intake From Diet and Supplements and Urinary Iodine Concentration in a Cohort of Pregnant Women in the United States

BACKGROUND

The DRI Estimated Average Requirement (EAR) in pregnancy for Iodine (I), an essential nutrient for fetal neurodevelopment, is 160 μg/d. Supplementation with 150 μg/d I/day is recommended during pregnancy, however, neither dietary intake or the combination of diet and supplement intake has been reported in US pregnant women.

OBJECTIVE

Determine iodine intake from diet and supplements and iodine status in pregnancy by urinary iodine concentration in a large cohort of pregnant women.

DESIGN

Pregnant women (n=750) completed the Diet History Questionnaire 2.0 from the National Institute of Cancer or multiple 24-hour recalls at baseline and identified their prenatal supplement(s). Dietary iodine intake was estimated using the USDA, FDA and ODS-NIH Database for the Iodine Content of Common Foods at enrollment, supplemental iodine intake throughout the study using content databases, and urinary iodine concentration (UIC) by the modified Sandell-Kolthoff reaction in samples collected between 14-20 weeks gestation (n=966).

RESULTS

The median intake of iodine from diet was 108.8 μg/d, and 63% (473/750) were below the Estimated Average Requirement (EAR). Furthermore, 65% (529/818) took a supplement containing iodine, however, only 32% (259/818) took ≥150 μg/d. Median intake increased to 188.5 μg/d with the inclusion of I from supplements, however , 41% (380/925) remained below the EAR even after supplementation suggesting inadequate intake in nearly half of the cohort. A similar 48% (467/966) had UIC ≤150 μg/L.

CONCLUSIONS

Assessment of iodine status by UIC and intake of iodine from diet and supplements support a high prevalence of iodine insufficiency during pregnancy in this large cohort of US women.

Identifying women who may benefit from higher dose omega-3 supplementation during pregnancy to reduce their risk of prematurity: exploratory analyses from the ORIP trial

OBJECTIVES

The risk factors for prematurity are multifactorial and include low omega-3 status. Omega-3 supplementation in pregnancy has been found to reduce prematurity risk, particularly among women with low omega-3 levels. This study aimed to identify maternal characteristics that predict whether women with a singleton pregnancy will benefit from omega-3 supplementation to reduce their risk of prematurity.

DESIGN

Exploratory analyses of a multicentre, double-blind randomised trial.

SETTING

6 tertiary care centres in four states in Australia.

PARTICIPANTS

5328 singleton pregnancies in 5305 women recruited before 20 weeks of gestation.

INTERVENTIONS

Fish oil capsules containing 900 mg omega-3 long-chain polyunsaturated fatty acids per day versus vegetable oil capsules consumed from enrolment until 34 weeks' gestation.

OUTCOME MEASURES

Early preterm birth (EPTB, <34 weeks' gestation) and preterm birth (PTB, <37 weeks' gestation) analysed using logistic regression models with interactions between treatment group and a range of maternal biological, clinical and demographic characteristics.

RESULTS

Omega-3 supplementation reduced the odds of EPTB for women with low total omega-3 status in early pregnancy (OR=0.30, 95% CI 0.10-0.93). No additional maternal characteristics influenced whether omega-3 supplementation reduced the odds of EPTB. For PTB, women were more likely to benefit from omega-3 supplementation if they were multiparous (OR=0.65, 95% CI 0.49-0.87) or avoided alcohol in the lead up to pregnancy (OR=0.62, 95% CI 0.45-0.86).

CONCLUSIONS

Our results support previous findings that women with low total omega-3 levels in early pregnancy are most likely to benefit from taking omega-3 supplements to reduce their risk of EPTB. Understanding how other maternal characteristics influence the effectiveness of omega-3 supplementation on reducing PTB requires further investigation.

TRIAL REGISTRATION NUMBER

ACTRN12613001142729.

Early and late preterm birth rates in participants adherent to randomly assigned high dose docosahexaenoic acid (DHA) supplementation in pregnancy

BACKGROUND

Intention-to-treat analyses do not address adherence. Per protocol analyses treat nonadherence as a protocol deviation and assess if the intervention is effective if followed.

OBJECTIVE

To determine the rate of early preterm birth (EPTB, <34 weeks gestation) and preterm birth (PTB, <37 weeks gestation) in participants who adhered to a randomly assigned docosahexaenoic acid (DHA) dose of 1000 mg/day.

STUDY DESIGN

Eleven hundred women with a singleton pregnancy were enrolled before 20-weeks' gestation, provided a capsule with 200 mg/day DHA and randomly assigned to two additional capsules containing a placebo or 800 mg of DHA. In the Bayesian Adaptive Design, new randomization schedules were determined at prespecified intervals. In each randomization, the group with the most EPTB was assigned fewer participants than the other group. Adherence was defined a priori as a postpartum red blood cell phospholipid DHA (RBC-PL-DHA) ≥5.5%.and post hoc as ≥8.0% RBC-PL-DHA, the latter after examination of postpartum RBC-PL-DHA. Bayesian mixture models were fitted for gestational age and dichotomized for EPTB and PTB as a function of baseline RBC-PL-DHA and dose-adherence. Bayesian hierarchical models were also fitted for EPTB by dose adherence and quartiles of baseline RBC-PL-DHA.

RESULTS

Adherence to the high dose using both RBC-PL-DHA cut points resulted in less EPTB compared to 200 mg [Bayesian posterior probability (pp) = 0.93 and 0.92, respectively]. For participants in the two lowest quartiles of baseline DHA status, adherence to the higher dose resulted in lower EPTB (≥5.5% RBC-PL-DHA, quartiles 1 and 2, pp = 0.95 and 0.96; ≥8% RBC-PL-DHA, quartiles 1 and 2, pp = 0.94 and 0.95). Using the Bayesian model, EPTB was reduced by 65%, from 3.45% to 1.2%, using both cut points. Adherence also reduced PTB before 35, 36 and 37 weeks using both cut points (pp ≥ 0.95). In general, performance of the nonadherent subgroup mirrored that of participants assigned to 200 mg.

CONCLUSION

Adherence to high dose DHA reduced EPTB and PTB. The largest effect of adherence on reducing EPTB was observed in women with low baseline DHA levels.

CLINICALTRIALS

gov (NCT02626299).

Docosahexaenoic acid (DHA) intake estimated from a 7-question survey identifies pregnancies most likely to benefit from high-dose DHA supplementation

BACKGROUND

Two randomized trials found women with low blood docosahexaenoic acid (DHA; an omega 3 fatty acid) had fewer early preterm births (<34 weeks gestation) if they were assigned to high dose DHA supplementation, however, there is currently no capacity for clinicians who care for pregnancies to obtain a blood assessment of DHA. Determining a way to identify women with low DHA intake whose risk could be lowered by high dose DHA supplementation is desired.

OBJECTIVE

To determine if assessing DHA intake can identify pregnancies that benefit from high dose DHA supplementation.

STUDY DESIGN

This secondary analysis used birth data from 1310 pregnant women who completed a 7-question food frequency questionnaire (DHA-FFQ) at 16.8 ± 2.5 weeks gestation that is validated to assess DHA status. They were then randomly assigned to a standard (200 mg/day) or high dose (800 or 1000 mg/day) DHA supplement for the remainder of pregnancy. Bayesian logistic regressions were fitted for early preterm birth and preterm birth as a function of DHA intake and assigned DHA dose.

RESULTS

Participants who consumed less than 150 mg/day DHA prior to 20 weeks' gestation (n = 810/1310, 58.1%) had a lower Bayesian posterior probability (pp) of early preterm birth if they were assigned to high dose DHA supplementation (1.4% vs 3.9%, pp = 0.99). The effect on preterm birth (<37 weeks) was also significant (11.3% vs 14.8%, pp = 0.97).

CONCLUSION

The DHA-FFQ can identify pregnancies that will benefit most from high dose DHA supplementation and reduce the risk of preterm birth. The DHA-FFQ is low burden to providers and patients and could be easily implemented in obstetrical practice.

The value of a two-armed Bayesian response adaptive randomization trial

We investigate the value of a two-armed Bayesian response adaptive randomization (RAR) design to investigate early preterm birth rates of high versus low dose of docosahexaenoic acid during pregnancy. Unexpectedly, the COVID-19 pandemic forced recruitment to pause at 1100 participants rather than the planned 1355. The difference in power between number of participants at the pause and planned was 87% and 90% respectively. We decided to stop the study. This paper describes how the RAR was used to execute the study. The value of RAR in two-armed studies is quite high and their use in the future is promising.

Nutrition Literacy Among Latina/x People During Pregnancy Is Associated With Socioeconomic Position

BACKGROUND

During pregnancy, Latina/x people experience nutrition and nutrition-related health inequities. Nutrition literacy is a potential factor impacted by these inequities. However, the nutrition literacy level of Latina/x people during pregnancy is not well investigated.

OBJECTIVES

The study aimed to assess the nutrition literacy level of Latina/x people during pregnancy and explore the association of nutrition literacy with socioeconomic position.

DESIGN

This was a cross-sectional study of data collected from 2016 to 2018 within the double-blinded, randomized clinical trial Assessment of Docosahexaenoic Acid on Reducing Early Preterm Birth.

PARTICIPANTS/SETTING

A total of 112 Latina/x people during pregnancy from the Kansas City metro area were included in this study.

MAIN OUTCOME MEASURES

Nutrition literacy level assessed between 12 and 20 gestational weeks using the Nutrition Literacy Assessment Instrument, both in English and Spanish.

STATISTICAL ANALYSES PERFORMED

Descriptive measures were used to describe the nutrition literacy level during pregnancy. Multiple logistic regression models were used to examine the association between low nutrition literacy and socioeconomic position, adjusting for age and race.

RESULTS

In this study, most participants demonstrated low nutrition literacy during pregnancy. Those with low nutrition literacy were 2 times more likely to have low annual household income (odds ratio [OR] = 2.74, 95% confidence interval [CI]: 0.99-7.59), 3 times more likely to prefer Spanish as their primary language of communication (OR = 3.03, 95% CI: 0.95-9.67), and 7 times more likely to be uninsured (OR = 7.47; 95% CI: 1.57-35.64).

CONCLUSIONS

Nutrition literacy scores during pregnancy were associated with variables of socioeconomic position. Future research should focus on nutrition literacy associations with health outcomes during pregnancy and interventions to improve the nutrition literacy level of primarily Spanish-speaking people who have low household incomes and are uninsured.

Higher Diet Quality in Latina Women during Pregnancy May Be Associated with Sociodemographic Factors

Acculturation contributes to low diet quality and can foster health inequities for Latina women during pregnancy. Conversely, nutrition literacy (NL) increases diet quality and could promote health equity. This study assessed the associations between the diet quality, acculturation, and NL of Latina women (n = 99) participating in the Assessment of Docosahexaenoic Acid On Reducing Early Preterm Birth (ADORE) study. Acculturation and nutrition literacy factored together tended to modify diet quality, but this was not statistically significant. Diet quality was associated with acculturation, age, and nativity. Most (76.8%) demonstrated low nutrition literacy. Women who were bicultural and were born in Latin American countries other than Mexico had lower diet quality scores than women who had lower acculturation and were born in Mexico. Women who were 35 years or older had better diet quality than those who were younger. Future studies are needed to explore diet quality differences for pregnant Latina women with high nutrition literacy and high acculturation, as well as for women from the Caribbean, Central and South American countries living in the US, to promote nutrition and maternal health for Latina women.

Neurodevelopment, nutrition and genetics. A contemporary retrospective on neurocognitive health on the occasion of the 100th anniversary of the National Institute of Nutrition, Hyderabad, India

In celebration of the centenary of the National Institute of Nutrition (NIN), Hyderabad, India (1918-2018), a symposium highlighted the progress in nutrition knowledge made over the century, as well as major gaps in implementation of that knowledge. Brain famine caused by a shortage of nutrients required for perinatal brain development has unfortunately become a global reality, even as protein-calorie famine was largely averted by the development of high yield crops. While malnutrition remains widespread, the neglect of global food policies that support brain development and maintenance are most alarming. Brain disorders now top the list of the global burden of disease, even with obesity rising throughout the world. Neurocognitive health, remarkably, is seldom listed among the non-communicable diseases (NCDs) and is therefore seldom considered as a component of food policy. Most notably, the health of mothers before conception and through pregnancy as mediated by proper nutrition has been neglected by the current focus on early death in non-neurocognitive NCDs, thereby compromising intellectual development of the ensuing generations. Foods with balanced essential fatty acids and ample absorbable micronutrients are plentiful for populations with access to shore-based foods, but deficient only a few kilometres away from the sea. Sustained access to brain supportive foods is a priority for India and throughout the world to enable each child to develop to their intellectual potential, and support a prosperous, just, and peaceful world. Nutrition education and food policy should place the nutritional requirements for the brain on top of the list of priorities.

Validation of an abbreviated food frequency questionnaire for estimating DHA intake of pregnant women in the United States

Docosahexaenoic acid (DHA) intake was estimated in pregnant women between 12- and 20-weeks' gestation using the National Cancer Institute's (NCI) Diet History Questionnaire-II (DHQ-II) and a 7-question screener designed to capture DHA intake (DHA Food Frequency Questionnaire, DHA-FFQ). Results from both methods were compared to red blood cell phospholipid DHA (RBC-DHA) weight percent of total fatty acids. DHA intake from the DHA-FFQ was more highly correlated with RBC-DHA (r_s=0.528) than the DHQ-II (r_s=0.352). Moreover, the DHA-FFQ allowed us to obtain reliable intake data from 1355 of 1400 participants. The DHQ-II provided reliable intake for only 847 of 1400, because many participants only partially completed it and it was not validated for Hispanic participants. Maternal age, parity, and socioeconomic status (SES) were also significant predictors of RBC-DHA. When included with estimated intake from the DHA-FFQ, the model accounted for 36% of the variation in RBC-DHA.

The Successful Synchronized Orchestration of an Investigator-Initiated Multicenter Trial Using a Clinical Trial Management System and Team Approach: Design and Utility Study

BACKGROUND

As the cost of clinical trials continues to rise, novel approaches are required to ensure ethical allocation of resources. Multisite trials have been increasingly utilized in phase 1 trials for rare diseases and in phase 2 and 3 trials to meet accrual needs. The benefits of multisite trials include easier patient recruitment, expanded generalizability, and more robust statistical analyses. However, there are several problems more likely to arise in multisite trials, including accrual inequality, protocol nonadherence, data entry mistakes, and data integration difficulties.

OBJECTIVE

The Biostatistics & Data Science department at the University of Kansas Medical Center developed a clinical trial management system (comprehensive research information system [CRIS]) specifically designed to streamline multisite clinical trial management.

METHODS

A National Institute of Child Health and Human Development-funded phase 3 trial, the ADORE (assessment of docosahexaenoic acid [DHA] on reducing early preterm birth) trial fully utilized CRIS to provide automated accrual reports, centralize data capture, automate trial completion reports, and streamline data harmonization.

RESULTS

Using the ADORE trial as an example, we describe the utility of CRIS in database design, regulatory compliance, training standardization, study management, and automated reporting. Our goal is to continue to build a CRIS through use in subsequent multisite trials. Reports generated to suit the needs of future studies will be available as templates.

CONCLUSIONS

The implementation of similar tools and systems could provide significant cost-saving and operational benefit to multisite trials.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02626299; https://tinyurl.com/j6erphcj.

Higher-Dose DHA Supplementation Modulates Immune Responses in Pregnancy and Is Associated with Decreased Preterm Birth

Pregnancy and parturition involve extensive changes in the maternal immune system. In our randomized, multi-site, double-blind superiority trial using a Bayesian adaptive design, we demonstrated that 1000 mg/day of docosahexaenoic acid (DHA) was superior to 200 mg/day in preventing both early preterm birth (less than 34 weeks' gestation) and preterm birth (less than 37 weeks' gestation). The goal of this secondary study is to compare the effects of 1000 mg/day versus 200 mg/day on maternal inflammation, a possible mechanism by which DHA may prevent preterm birth. Maternal blood samples were collected at enrollment (12-20 weeks' gestation) and at delivery. Red blood cell DHA levels were measured by gas chromatography, and plasma concentrations of sRAGE, IL-6, IL-1β, TNFα, and INFγ were measured by ELISA. Data were analyzed for associations with the DHA dose, gestational age at birth, and preterm birth (<37 weeks). Higher baseline and lower delivery levels of maternal sRAGE were associated with a greater probability of longer gestation and delivery at term gestation. Higher-dose DHA supplementation increased the probability of a smaller decrease in delivery sRAGE levels. Higher IL-6 concentrations at delivery were associated with the probability of delivering after 37 weeks, and higher-dose DHA supplementation increased the probability of greater increases in IL-6 concentrations between enrollment and delivery. These data provide a proposed mechanistic explanation of how a higher dose of DHA during pregnancy provides immunomodulatory regulation in the initiation of parturition by influencing sRAGE and IL-6 levels, which may explain its ability to reduce the risk of preterm birth.

Next generation strategies for preventing preterm birth

Preterm birth (PTB) is defined as delivery before 37 weeks of gestation. Globally, 15 million infants are born prematurely, putting these children at an increased risk of mortality and lifelong health challenges. Currently in the U.S., there is only one FDA approved therapy for the prevention of preterm birth. Makena is an intramuscular progestin injection given to women who have experienced a premature delivery in the past. Recently, however, Makena failed a confirmatory trial, resulting the Center for Drug Evaluation and Research's (CDER) recommendation for the FDA to withdrawal Makena's approval. This recommendation would leave clinicians with no therapeutic options for preventing PTB. Here, we outline recent interdisciplinary efforts involving physicians, pharmacologists, biologists, chemists, and engineers to understand risk factors associated with PTB, to define mechanisms that contribute to PTB, and to develop next generation therapies for preventing PTB. These advances have the potential to better identify women at risk for PTB, prevent the onset of premature labor, and, ultimately, save infant lives.

Higher dose docosahexaenoic acid supplementation during pregnancy and early preterm birth: A randomised, double-blind, adaptive-design superiority trial

BACKGROUND

Several meta analyses have concluded n-3 fatty acids, including docosahexaenoic acid (DHA), reduce early preterm birth (EPB, < 34 weeks), however, the amount of DHA required is unclear. We hypothesized that 1000 mg DHA per day would be superior to 200 mg, the amount in most prenatal supplements.

METHODS

This randomised, multicentre, double-blind, adaptive-design, superiority trial was conducted in three USA medical centres. Women with singleton pregnancies and 12 to 20 weeks gestation were eligible. randomization was generated in SAS® by site in blocks of 4. The planned adaptive design periodically generated allocation ratios favoring the better performing dose. Managing study personnel were blind to treatment until 30 days after the last birth. The primary outcome was EPB by dose and by enrolment DHA status (low/high). Bayesian posterior probabilities (pp) were determined for planned efficacy and safety outcomes using intention-to-treat. The study is registered with ClinicalTrials.gov (NCT02626299) and closed to enrolment.

FINDINGS

Eleven hundred participants (1000 mg, n = 576; 200 mg, n = 524) were enrolled between June 8, 2016 and March 13, 2020 with the last birth September 5, 2020. 1032 (n = 540 and n = 492) were included in the primary analyses. The higher dose had a lower EPB rate [1.7% (9/540) vs 2.4% (12/492), pp=0.81] especially if participants had low DHA status at enrolment [2.0% (5/249) vs 4.1%, (9/219), pp=0.93]. Participants with high enrolment DHA status did not realize a dose effect [1000 mg: 1.4% (4/289); 200 mg: 1.1% (3/271), pp = 0.57]. The higher dose was associated with fewer serious adverse events (maternal: chorioamnionitis, premature rupture of membranes and pyelonephritis; neonatal: feeding, genitourinary and neurologic problems, all pp>0.90).

INTERPRETATION

Clinicians could consider prescribing 1000 mg DHA daily during pregnancy to reduce EPB in women with low DHA status if they are able to screen for DHA.

FUNDING

The National Institutes of Health Child Health and Human Development (NICHD) funded the study. Life's DHA™-S oil, DSM Nutritional Products LLC, Switzerland provided all capsules.

Long-chain omega-3 fatty acid serum concentrations across life stages in the USA: an analysis of NHANES 2011-2012

OBJECTIVE

To determine reference ranges of circulating long-chain (LC) omega-3 fatty acids: eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) in a nationally representative population of Americans. To provide context, serum concentrations of LC omega-3 were compared with concentrations associated with consuming the recommended amount of EPA and DHA by the Dietary Guidelines for Americans (DGA) and the Omega-3 Index (EPA+DHA).

DESIGN

Cross-sectional population-based study.

SETTING

The National Health and Nutrition Examination Survey 2011-2012 cycle.

PARTICIPANTS

Participants with fatty acids measured in serum: 945 children, age 3-19 years, and 1316 adults, age 20 and older.

MAIN MEASURE

Serum EPA, DPA, DHA and sum of LC omega-3 fatty acids expressed as per cent of total fatty acids.

RESULTS

Among children, mean (SE) serum concentrations of EPA, DHA and omega-3s were 0.28% (0.01), 1.07% (0.02) and 1.75% (0.03). Among adults, mean (SE) of EPA, DHA and omega-3s were 0.61% (0.02), 1.38% (0.05) and 2.43% (0.08), all of which were significantly higher than corresponding serum fatty acid concentrations in children (p<0.001). Despite recommendations for higher intake, pregnant and/or breastfeeding women had mean (SE) EPA, DHA and LC omega-3 concentrations of 0.34% (0.07), 1.52% (0.08) and 2.18% (0.15), which were comparable to women of childbearing age; p=0.17, p=0.10 and p=0.73. Over 95% of children and 68% of adults had LC omega-3 concentrations below those associated with the DGA recommendation. Approximately 89% of adults had an Omega-3 Index in the high cardiovascular risk category.

CONCLUSIONS

Contemporary reference ranges for circulating LC omega-3s are critical for setting public health recommendations. Our findings show the need for continued emphasis on regular consumption of LC omega-3s among Americans, particularly considering the importance of LC omega-3s in cardiovascular health, brain health and development throughout life.

Multiple Micronutrients and Docosahexaenoic Acid Supplementation during Pregnancy: A Randomized Controlled Study

Maternal dietary intake during pregnancy needs to meet increased nutritional demands to maintain metabolism and to support fetal development. Docosahexaenoic acid (DHA) is essential for fetal neuro-/visual development and in immunomodulation, accumulating rapidly within the developing brain and central nervous system. Levels available to the fetus are governed by the maternal diet. In this multicenter, parallel, randomized controlled trial, we evaluated once-daily supplementation with multiple micronutrients and DHA (i.e., multiple micronutrient supplementation, MMS) on maternal biomarkers and infant anthropometric parameters during the second and third trimesters of pregnancy compared with no supplementation. Primary efficacy endpoint: change in maternal red blood cell (RBC) DHA (wt% total fatty acids) during the study. Secondary variables: other biomarkers of fatty acid and oxidative status, vitamin D, and infant anthropometric parameters at delivery. Supplementation significantly increased RBC DHA levels, the omega-3 index, and vitamin D levels. Subscapular skinfold thickness was significantly greater with MMS in infants. Safety outcomes were comparable between groups. This first randomized controlled trial of supplementation with multiple micronutrients and DHA in pregnant women indicated that MMS significantly improved maternal DHA and vitamin D status in an industrialized setting-an important finding considering the essential roles of DHA and vitamin D.

Inhibitory effect of omega-3 fatty acids on alveolar bone resorption and osteoclast differentiation

In this study, a Porphyromonas gingivalis (P.g.)-infected mouse periodontitis model was used to investigate the effect of omega-3 fatty acid intake on differentiation and maturation of cultured osteoclast. Four-week-old C57BL/6JJcl mice were divided into four groups according to the diets they were fed from the beginning of the experiment (i.e., food containing omega-3 or omega-6 fatty acids) and whether they were orally administered P.g. Thirty-three days after beginning the experiment, bone marrow cells were sampled from the femoral bone of mice from each group and differentiated into osteoclasts; the effects of the ingestion of different fatty acids were subsequently investigated. There was no statistical interaction between the different fatty acids and P.g. infection on the number of osteoclasts (P = 0.6). However, the fatty acid type affected the number of osteoclasts in mice (P = 0.0013), with the omega-3 groups demonstrating lower osteoclast numbers than the omega-6 groups. Furthermore, the addition of resolvin E1 (RvE1), which is an omega-3 fatty acid-derived lipid mediator, suppressed the differentiation of mouse cultured osteoclasts (P < 0.0001). Therefore, the ingestion of omega-3 fatty acids may suppress osteoclast differentiation while inhibiting bone resorption and tissue destruction due to periodontitis.

Reducing the Risk of Preterm Birth by Ambulatory Risk Factor Management

BACKGROUND

The preterm birth rate in Germany has remained unchanged at 8-9% since 2009. Preterm birth is the most common cause of neonatal morbidity and mortality. In the absence of a causal treatment, it is important to lower the risk of preterm birth by preventive measures in prenatal outpatient care.

METHODS

This review is based on pertinent publications from the years 2000-2019 that were retrieved by a selective search in PubMed.

RESULTS

The clinical risk factors for preterm birth-known mainly from retrospective cohort studies-include previous preterm birth (adjusted odds ratio [aOR]: 3.6), multiple pregnancy (relative risk [RR]: 7.7), nicotine consumption (aOR: 1.7), and a short uterine cervix, i.e., <25 mm in the second trimester (aOR: 6.9). In women with a short cervix, vaginally administered progesterone significantly lowers the preterm birth rate (22.5% vs. 14.1% for birth before 33 weeks of gestation, RR: 0.62; 95% confidence interval [0.47; 0.81]). Nicotine abstinence is associated with a lower pre- term birth rate as well (aOR: 0.91; [0.88; 0,.94]), while working more than 40 hours per week (aOR: 1.25; [1,.01; 1,.54]) and heavy lifting during pregnancy (hazard ratio [HR]: 1.43; [1.13; 1.80]) are associated with a higher preterm birth rate. Avoidance of physical exertion, or bed rest, in the face of impending preterm birth does not lower the preterm birth rate, but it does increase the risk of complications, such as thromboembolism.

CONCLUSION

The meticulous assessment and elimination of treatable risk factors at the outset of ambulatory prenatal care can help lower the preterm birth rate. Further velopment of causally directed treat- ments (e.g., changes of relevant environmental and epigenetic factors).

Preterm Birth: A Narrative Review of the Current Evidence on Nutritional and Bioactive Solutions for Risk Reduction

Preterm birth (PTB) (<37 weeks of gestation) is the leading cause of newborn death and a risk factor for short and long-term adverse health outcomes. Most cases are of unknown cause. Although the mechanisms triggering PTB remain unclear, an inappropriate increase in net inflammatory load seems to be key. To date, interventions that reduce the risk of PTB are effective only in specific groups of women, probably due to the heterogeneity of its etiopathogenesis. Use of progesterone is the most effective, but only in singleton pregnancies with history of PTB. Thus, primary prevention is greatly needed and nutritional and bioactive solutions are a promising alternative. Among these, docosahexaenoic acid (DHA) is the most promising to reduce the risk for early PTB. Other potential nutrient interventions include the administration of zinc (possibly limited to populations with low nutritional status or poor zinc status) and vitamin D; additional preliminary evidence exists for vitamin A, calcium, iron, folic acid, combined iron-folate, magnesium, multiple micronutrients, and probiotics. Considering the public health relevance of PTB, promising interventions should be studied in large and well-designed clinical trials. The objective of this review is to describe, summarize, and discuss the existing evidence on nutritional and bioactive solutions for reducing the risk of PTB.

A Prenatal DHA Test to Help Identify Women at Increased Risk for Early Preterm Birth: A Proposal

Fish intake and docosahexaenoic acid (DHA), a nutrient found in fish, have been favorably linked to several pregnancy outcomes. The risk of early preterm birth (ePT, <34 weeks gestation) is associated with low fish intake and DHA blood levels and can be reduced by supplemental DHA. Here, we summarize the evidence linking blood DHA levels with risk for ePT birth, and based on the available studies, propose that women who are pregnant or trying to become pregnant aim for a red blood cell (RBC) DHA value of at least 5% (of total RBC fatty acids). In the US, ~70% of women of childbearing age are likely below this cut-point, and dietary intake data suggest that this group, including pregnant women, consumes ~60 mg/day DHA and that >90% of this group do not take an omega-3 supplement. Since the recommendations for women to consume fish and to take a 200 mg DHA supplement during pregnancy are not being heeded generally, there is a need to motivate practitioners and pregnant women to attend to these recommendations. Having an objective prenatal blood DHA test could provide such motivation. More research is needed to test the clinical utility of this proposed target prenatal DHA level.

Omega-3 fatty acid addition during pregnancy

BACKGROUND

Higher intakes of foods containing omega-3 long-chain polyunsaturated fatty acids (LCPUFA), such as fish, during pregnancy have been associated with longer gestations and improved perinatal outcomes. This is an update of a review that was first published in 2006.

OBJECTIVES

To assess the effects of omega-3 LCPUFA, as supplements or as dietary additions, during pregnancy on maternal, perinatal, and neonatal outcomes and longer-term outcomes for mother and child.

SEARCH METHODS

For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (16 August 2018), and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing omega-3 fatty acids (as supplements or as foods, stand-alone interventions, or with a co-intervention) during pregnancy with placebo or no omega-3, and studies or study arms directly comparing omega-3 LCPUFA doses or types. Trials published in abstract form were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, extracted data, assessed risk of bias in trials and assessed quality of evidence for prespecified birth/infant, maternal, child/adult and health service outcomes using the GRADE approach.

MAIN RESULTS

In this update, we included 70 RCTs (involving 19,927 women at low, mixed or high risk of poor pregnancy outcomes) which compared omega-3 LCPUFA interventions (supplements and food) compared with placebo or no omega-3. Overall study-level risk of bias was mixed, with selection and performance bias mostly at low risk, but there was high risk of attrition bias in some trials. Most trials were conducted in upper-middle or high-income countries; and nearly half the trials included women at increased/high risk for factors which might increase the risk of adverse maternal and birth outcomes.Preterm birth < 37 weeks (13.4% versus 11.9%; risk ratio (RR) 0.89, 95% confidence interval (CI) 0.81 to 0.97; 26 RCTs, 10,304 participants; high-quality evidence) and early preterm birth < 34 weeks (4.6% versus 2.7%; RR 0.58, 95% CI 0.44 to 0.77; 9 RCTs, 5204 participants; high-quality evidence) were both lower in women who received omega-3 LCPUFA compared with no omega-3. Prolonged gestation > 42 weeks was probably increased from 1.6% to 2.6% in women who received omega-3 LCPUFA compared with no omega-3 (RR 1.61 95% CI 1.11 to 2.33; 5141 participants; 6 RCTs; moderate-quality evidence).For infants, there was a possibly reduced risk of perinatal death (RR 0.75, 95% CI 0.54 to 1.03; 10 RCTs, 7416 participants; moderate-quality evidence: 62/3715 versus 83/3701 infants) and possibly fewer neonatal care admissions (RR 0.92, 95% CI 0.83 to 1.03; 9 RCTs, 6920 participants; moderate-quality evidence - 483/3475 infants versus 519/3445 infants). There was a reduced risk of low birthweight (LBW) babies (15.6% versus 14%; RR 0.90, 95% CI 0.82 to 0.99; 15 trials, 8449 participants; high-quality evidence); but a possible small increase in large-for-gestational age (LGA) babies (RR 1.15, 95% CI 0.97 to 1.36; 6 RCTs, 3722 participants; moderate-quality evidence, for omega-3 LCPUFA compared with no omega-3. Little or no difference in small-for-gestational age or intrauterine growth restriction (RR 1.01, 95% CI 0.90 to 1.13; 8 RCTs, 6907 participants; moderate-quality evidence) was seen.For the maternal outcomes, there is insufficient evidence to determine the effects of omega-3 on induction post-term (average RR 0.82, 95% CI 0.22 to 2.98; 3 trials, 2900 participants; low-quality evidence), maternal serious adverse events (RR 1.04, 95% CI 0.40 to 2.72; 2 trials, 2690 participants; low-quality evidence), maternal admission to intensive care (RR 0.56, 95% CI 0.12 to 2.63; 2 trials, 2458 participants; low-quality evidence), or postnatal depression (average RR 0.99, 95% CI 0.56 to 1.77; 2 trials, 2431 participants; low-quality evidence). Mean gestational length was greater in women who received omega-3 LCPUFA (mean difference (MD) 1.67 days, 95% CI 0.95 to 2.39; 41 trials, 12,517 participants; moderate-quality evidence), and pre-eclampsia may possibly be reduced with omega-3 LCPUFA (RR 0.84, 95% CI 0.69 to 1.01; 20 trials, 8306 participants; low-quality evidence).For the child/adult outcomes, very few differences between antenatal omega-3 LCPUFA supplementation and no omega-3 were observed in cognition, IQ, vision, other neurodevelopment and growth outcomes, language and behaviour (mostly low-quality to very low-quality evidence). The effect of omega-3 LCPUFA on body mass index at 19 years (MD 0, 95% CI -0.83 to 0.83; 1 trial, 243 participants; very low-quality evidence) was uncertain. No data were reported for development of diabetes in the children of study participants.

AUTHORS' CONCLUSIONS

In the overall analysis, preterm birth < 37 weeks and early preterm birth < 34 weeks were reduced in women receiving omega-3 LCPUFA compared with no omega-3. There was a possibly reduced risk of perinatal death and of neonatal care admission, a reduced risk of LBW babies; and possibly a small increased risk of LGA babies with omega-3 LCPUFA.For our GRADE quality assessments, we assessed most of the important perinatal outcomes as high-quality (e.g. preterm birth) or moderate-quality evidence (e.g. perinatal death). For the other outcome domains (maternal, child/adult and health service outcomes) GRADE ratings ranged from moderate to very low, with over half rated as low. Reasons for downgrading across the domain were mostly due to design limitations and imprecision.Omega-3 LCPUFA supplementation during pregnancy is an effective strategy for reducing the incidence of preterm birth, although it probably increases the incidence of post-term pregnancies. More studies comparing omega-3 LCPUFA and placebo (to establish causality in relation to preterm birth) are not needed at this stage. A further 23 ongoing trials are still to report on over 5000 women, so no more RCTs are needed that compare omega-3 LCPUFA against placebo or no intervention. However, further follow-up of completed trials is needed to assess longer-term outcomes for mother and child, to improve understanding of metabolic, growth and neurodevelopment pathways in particular, and to establish if, and how, outcomes vary by different types of omega-3 LCPUFA, timing and doses; or by characteristics of women.

Prevention of Prematurity: Advances and Opportunities

Preterm birth (PTB) rate varies widely and has significant racial and ethnic disparities. Although causal mechanisms are ill understood, socioenvironment, phenotype, and genotype provide insight into pathways for preventing PTB. Data suggest varied response to current medical interventions is explicable Approved by underlying pharmacogenomics. Currently, prevention focuses on minimizing iatrogenic PTB and risk reduction especially in those with prior PTB using proven medical and public health strategies. In the future, preventive approaches will be based on better understanding of sociodemography, nutrition, lifestyles, and underlying individual genetic and epigenetic variation. Statistical approaches and "big-data" models are critical in future study.

Effects of dietary omega-3 PUFAs on growth and development: Somatic, neurobiological and reproductive functions in a murine model

Omega-3 polyunsaturated fatty acids (ω-3 PUFAs) are relevant to fetal and infant growth and development. Objective: to assess whether long-term exposure to dietary ω-3 PUFA imbalance alters pre- and/or postnatal pups' development and reproductive function later in life. Mice dams were fed with ω-3 PUFA Control (soybean oil, 7%), Deficient (sunflower oil, 7%) or Excess (blend oil; 4.2% cod-liver+2.8% soybean) diet before conception and throughout gestation-lactation and later on, their pups received the same diet from weaning to adulthood. Offspring somatic, neurobiological and reproductive parameters were evaluated. Excess pups were lighter during the preweaning period and shorter in length from postnatal day (PND) 7 to 49, compared to Control pups (P<.05). On PND14, the percentage of pups with eye opening in Excess group was lower than those from Control and Deficient groups (P<.05). In Excess female offspring, puberty onset (vaginal opening and first estrus) occurred significantly later and the percentage of parthenogenetic oocytes on PND63 was higher than Control and Deficient ones (P<.05). Deficient pups were shorter in length (males: on PND14, 21, 35 and 49; females: on PND14, 21 and 42) compared with Control pups (P<.05). Deficient offspring exhibited higher percentage of bending spermatozoa compared to Control and Excess offspring (P<.05). These results show that either an excessively high or insufficient ω-3 PUFA consumption prior to conception until adulthood seems inadvisable because of the potential risks of short-term adverse effects on growth and development of the progeny or long-lasting effects on their reproductive maturation and function.