Association of folate and vitamin B12 imbalance with adverse pregnancy outcomes among 11,549 pregnant women: An observational cohort study

Assessing the relationship between serum vitamin A, C, E, D, and B12 levels and preeclampsia

OBJECTIVE

Micronutrients play an important role in maintaining physiological functions while preventing complications associated with pregnancy. The main aim of this study was to evaluate the possible associations between vitamins A, C, D, E, B12, and preeclampsia using a retrospective analytical approach.

METHODS

This retrospective study enrolled pregnant women who attended routine antenatal checkups between January 2021 and January 2023 at the Obstetrics and Gynecology Hospital of Fudan University. One thousand pregnant women aged 18-50 years whose serum vitamin assessments were conducted during 12-20 weeks of gestation were enrolled. Inclusion criteria: women with preeclampsia, singleton pregnancies, and no previous history of hypertension or preeclampsia. Exclusion criteria: metabolic disorders, multiple pregnancies, and other specified exclusions. Approval of the hospital's ethics committee; all participants gave written informed consent. Demographic data analyzed include age, BMI, and gestational age, showing no significant differences in age span between groups (p > .05).

RESULTS

In the preeclampsia group, the serum level of vitamin A stands at 1.08 ± 0.29 μmol/L, which is lower than the control group of 1.13 ± 0.31 μmol/L (p < .05). Mean serum levels of vitamin C in preeclampsia are 51.81 ± 13.15 μmol/L, which was lower than in the control group, where it was 59.67 ± 16.40 μmol/L (p < .05). The mean serum vitamin B12 level in preeclampsia is 158.28 ± 46.77 pmol/L, lower than the 165.61 ± 40.99 pmol in the control group (p < .05). The two groups had no significant difference in serum vitamin E and vitamin D levels (p > .05).

CONCLUSION

Serum vitamins A, C, and B12 at 12 to 20 weeks of pregnancy might be important predisposing factors for preeclampsia. They can be used as indicators of preeclampsia severity and offer clinical detection even before the patient presents with symptoms.

Maternal obesity and offspring metabolism: revisiting dietary interventions

Maternal obesity increases the risk of metabolic disorders in offspring. Understanding the mechanisms underlying the transgenerational transmission of metabolic diseases is important for the metabolic health of future generations. More research is needed to elucidate the mechanisms underlying the associated risks and their clinical implications because of the inherently complex nature of transgenerational metabolic disease transmission. Diet is a well-recognized risk factor for the development of obesity and other metabolic diseases, and rational dietary interventions are potential therapeutic strategies for their prevention. Despite extensive research on the physiological effects of diet on health and its associated mechanisms, little work has been devoted to understanding the effects of early-life dietary interventions on the metabolic health of offspring. In addition, existing dietary interventions are insufficient to meet clinical needs. Here, we discuss the literature on the effects of maternal obesity on the metabolic health of offspring, focusing on the mechanisms underlying the transgenerational transmission of metabolic diseases. We revisit current dietary interventions and describe their strengths and weaknesses in ameliorating maternal obesity-induced metabolism-related disorders in offspring. We also propose innovative strategies, such as the use of precision nutrition and fecal microbiota transplantation, which may limit the vicious cycle of intergenerational metabolic disease transmission.

The Effect of Maternal Haemoglobinopathies and Iron Deficiency Anaemia on Foetal Growth Restriction: A Systematic Review and Meta-Analysis

Maternal anaemia is a significant global health issue that adversely affects both maternal and foetal outcomes, particularly, intrauterine growth restriction (IUGR). This systematic review and meta-analysis aimed to consolidate existing evidence on the impact of maternal anaemia on the risk of IUGR. We conducted a comprehensive search across PubMed, Embase, Cochrane and Web of Science until 28 February 2024. Eligible studies included observational designs that reported maternal anaemia and its association with IUGR or small for gestational age (SGA) outcomes. The pooled odds ratios (ORs) were calculated using a random-effects model and heterogeneity was assessed with the I² statistic. The R software (version 4.3) was used for statistical analyses. A total of 38 studies involving 3,871,849 anaemic and 27,978,450 non-anaemic pregnant women were included. The pooled analysis demonstrated that anaemia in pregnancy is associated with a significantly increased risk of IUGR (OR = 1.30, 95% CI: 1.05-1.62, I² = 97%). Subgroup analyses by anaemia severity showed non-significant associations for mild (OR = 0.84, 95% CI: 0.58-1.23) and moderate anaemia (OR = 0.98, 95% CI: 0.48-1.98), while severe anaemia indicated a higher, though non-significant, risk of IUGR (OR = 1.42, 95% CI: 0.69-2.93). Maternal anaemia is associated with a heightened risk of IUGR, highlighting the critical need for effective management and early intervention strategies within prenatal care settings. Future research should focus on elucidating the effects of different severities of anaemia on birth outcomes, including IUGR and long-term effects later in life.

Vitamin B12 and Autism Spectrum Disorder: A Review of Current Evidence

Vitamin B12 (cobalamin) plays a crucial role in neurodevelopment, particularly during pregnancy and early childhood. It is essential for DNA synthesis, red blood cell formation, and nervous system function. Maternal B12 levels are particularly important, as they influence fetal brain development. Inadequate maternal intake during pregnancy may lead to altered neurodevelopmental trajectories and increase the risk of ASD. Postnatally, insufficient dietary cobalamin in infants and young children could further contribute to cognitive and behavioral impairments. One potential mechanism linking low B12 levels to ASD involves its role in the gut microbiota balance. Dysbiosis, commonly observed in individuals with ASD, is associated with increased gut permeability, low-grade inflammation, and disruptions in the gut-brain axis, all of which may contribute to ASD symptoms. Additionally, B12 is essential for neurotransmitter metabolism, particularly in the synthesis of serotonin and dopamine, which regulate mood, cognition, and behavior. Cobalamin also plays a key role in neuronal myelination, which ensures efficient signal transmission in the nervous system. Disruptions in these processes could underlie some of the cognitive and behavioral features associated with ASD. Despite growing evidence, the link between B12 and ASD remains inconclusive due to inconsistent findings across studies. Research suggests that B12 levels may serve as a potential biomarker for disease progression and treatment response. However, many studies rely on single-time-point measurements, failing to account for individual variability, genetic predispositions, dietary intake, and environmental factors, all of which can influence B12 levels and ASD risk. Further longitudinal studies are needed to clarify this relationship.

Global and regional incidence of intrahepatic cholestasis of pregnancy: a systematic review and meta-analysis

BACKGROUND

Intrahepatic cholestasis of pregnancy (ICP) can be a source of significant distress for both pregnant women and the fetus, impairing the quality of life and well-being of pregnant women, leading to psychological disorders among pregnant women with severe or recurrent ICP, and causing life-threatening complications among fetuses. Regrettably, our current understanding of ICP globally is limited, lacking a comprehensive estimation of its incidence. Therefore, in this systematic review and meta-analysis, we aimed to investigate the global and regional incidence of ICP and identify factors that account for its variety across studies.

METHODS

A comprehensive search strategy was implemented across PubMed, Scopus, and Web of Science databases. To stabilize the variance, the Freeman-Tukey double arcsine transformation was employed. Subgroup analyses were conducted based on continent, publication type, study design and timing, regional classifications, developmental status, and World Bank income grouping. A multivariate meta-regression analysis was performed to estimate the effects of the continuous moderators on the effect size.

RESULTS

A total of 42,972,872 pregnant women were analyzed from 302 studies. The overall pooled incidence [95% confidence interval] of ICP was 2.9% [2.5, 3.3]. Studies with larger sample sizes tended to provide significantly lower estimates of ICP incidence: 1.6% [1.3, 2] vs 4.7% [3.9, 5.5]. Asia had the highest incidence of ICP among the continents, whereas Oceania had the lowest. Countries that were classified as developed and with higher income had a lower incidence of ICP than those classified as developing and low and middle income.

CONCLUSIONS

The findings of this study will provide valuable insights into the current knowledge regarding the association of the quality of public health and socioeconomic variations with the incidence of ICP on a global scale.

Impact of serum retinol-binding protein 4 levels in late pregnancy on the incidence of small/large for gestational age infants among 11,854 pregnant women: A retrospective study

BACKGROUND

There is still uncertainty regarding the association between maternal serum levels of retinol-binding protein 4 (RBP4) and pregnancy outcomes. This study aimed to determine the association between RBP4 levels and incidence of small/large for gestational age (SGA/LGA) infants among the Chinese population.

METHODS

This was a retrospective study of 11,854 pregnant women who delivered at Changzhou Maternal and Child Health Care Hospital between 2016 and 2017 and whose serum RBP4 levels were measured at the time of admission. The incidence of SGA/LGA deliveries was retrieved from the medical records of the participants.

RESULTS

Maternal RBP4 levels in the second, third and fourth quartiles (28.8-34.0, 34.1-40.0, and >40.0 mg/L, respectively) were associated with lower birthweights relative to those in the first quartile (<28.8 mg/L), with estimated average decreases of 51.30 g (95% CI: -70.51, -32.10), 86.86 g (95% CI: -106.50, -67.22) and 124.08 g (95% CI: -144.51, -103.64), respectively (P for trend <0.01). Pregnant women in the fourth quartile for RBP4 levels had a greater SGA risk (OR: 2.14, 95% CI: 1.72, 2.65) and lower LGA risk (OR: 0.53, 95% CI: 0.45, 0.63) than those in the first quartile after controlling for demographic variables, gestational age, pregnancy complications and other laboratory results. The sensitivity analysis indicated the consistency of these findings.

CONCLUSION

High RBP4 levels in late pregnancy are associated with an increased SGA risk and decreased LGA risk, indicating that serum RBP4 levels at the time of admission for delivery could be a promising predictor of SGA/LGA delivery.

Assessment of Vitamin D, Vitamin B12, and Folate Levels in Recently Identified Pregnant Females

Background: Pregnancy is a critical period where optimal maternal and fetal health depends on adequate nutritional status. Deficiencies in essential vitamins, such as vitamin D, vitamin B12, and folate, can result in adverse health outcomes. Objective: This study aims to assess the serum levels of vitamin D, vitamin B12, and folate in early pregnancy. Methodology: This cross-sectional research was conducted at Kurdistan Private Hospital in Duhok, Kurdistan Region of Iraq, from September 2022 to October 2023. The study included 150 pregnant women, with ages ranging from 18 to 45 years. Serum levels of vitamin D, vitamin B12, and folate were measured using the Automatic Clinical Chemistry Analyzer COBAS e 411 (Roche Diagnostics, Basel, Switzerland). Results: The mean age of the participants was 29 years (standard deviation [SD] = 6.2 years), with ages ranging from 18 to 45 years. The average serum human chorionic gonadotropin (HCG) level was 4,292 mIU/mL (SD = 3,947 mIU/mL), with a range of 98 to 10,000 mIU/mL. The mean serum levels were 17.8 ng/mL (SD = 11.6) for vitamin D, 367 pg/mL (SD = 245) for vitamin B12, and 11.5 ng/mL (SD = 4.6) for folate. The prevalence of vitamin D deficiency was significant, with 92 participants (61.3%) having levels below 20 ng/mL, 39 participants (26%) having insufficient levels ranging from 20 to 29 ng/mL, and only 19 participants (12.7%) having sufficient levels between 30 and 100 ng/mL. No cases of vitamin D toxicity (>150 ng/mL) were observed. Regarding vitamin B12, 32 participants (21.3%) had deficient levels (<200 pg/mL), while 118 participants (78.7%) had normal levels. Folate analysis revealed that 3 participants (2%) had moderate deficiency (2-3 ng/mL), 14 participants (9.3%) had mild deficiency (3-6 ng/mL), and there were no cases of severe folate deficiency (<2 ng/mL). Pearson correlation analysis showed weak correlations between the study variables, with the strongest being a weak negative correlation between age and serum folate levels (-0.18). Conclusions: The study found a high prevalence of vitamin D deficiency among the pregnant women included in the study, while the levels of folate and vitamin B12 were comparable to worldwide estimates. These findings focus attention on the importance of monitoring and addressing nutritional deficiencies at the beginning and throughout pregnancy. They also underline the need for preventive health interventions to correct these deficiencies and achieve the best outcomes for both maternal and fetal health.

Association of maternal and cord vitamin B12 levels with anthropometry in term neonates born to malnourished mothers in coastal South India

Background

Malnourished pregnant women are at increased risk of micronutrient deficiency. We assessed the vitamin B12 status in both malnourished and normally nourished pregnant women and their neonates. Additionally, we studied the association between maternal B12 levels, cord B12 levels and neonatal anthropometry.

Methods

This cross-sectional study enrolled 63 malnourished and 63 normally nourished mothers and neonates. Maternal and cord blood samples were collected at the time of delivery for estimation of vitamin B12 levels. Maternal and cord vitamin B12 levels were compared using the Mann-Whitney U test. Neonatal anthropometry was correlated with maternal and cord B12 levels using Spearman's correlation. Data were analyzed using SPSS version 25.

Results

Mean maternal age was 26.58 yrs. The median cord B12 levels were lower than the maternal B12 levels. Maternal B12 levels showed a strong positive correlation with cord B12 levels (rho = 0.879; p < 0.001). Maternal (p < 0.001) and cord (p < 0.001) vitamin B12 levels were significantly lower in the malnourished group than in the normally nourished group. In malnourished group, 66.8% mothers and 95.2% neonates were Vitamin B12 deficient, whereas 1.5% mothers and 4.7% neonates were vitamin B12 deficient in normally nourished group. In the malnourished group, maternal B12 levels were positively correlated with birth weight (rho 0.363, p = 0.003) and length (rho 0.330, p =0.008), whereas cord B12 levels were positively correlated with birth weight in the normally nourished group. (rho 0.277 p= 0.028).

Conclusion

High rates of vitamin B12 deficiency were observed in malnourished mothers and neonates. There was a positive correlation between birth weight, length, and maternal vitamin B12 levels in malnourished mothers. These findings emphasize the need to address maternal malnutrition and vitamin B12 deficiency to improve neonatal health.

Associations of prenatal one-carbon metabolism nutrients and metals with epigenetic aging biomarkers at birth and in childhood in a US cohort

Epigenetic gestational age acceleration (EGAA) at birth and epigenetic age acceleration (EAA) in childhood may be biomarkers of the intrauterine environment. We investigated the extent to which first-trimester folate, B12, 5 essential, and 7 non-essential metals in maternal circulation are associated with EGAA and EAA in early life. Bohlin EGAA and Horvath pan-tissue and skin and blood EAA were calculated using DNA methylation measured in cord blood (N=351) and mid-childhood blood (N=326; median age = 7.7 years) in the Project Viva pre-birth cohort. A one standard deviation increase in individual essential metals (copper, manganese, and zinc) was associated with 0.94-1.2 weeks lower Horvath EAA at birth, and patterns of exposures identified by exploratory factor analysis suggested that a common source of essential metals was associated with Horvath EAA. We also observed evidence nonlinear associations of zinc with Bohlin EGAA, magnesium and lead with Horvath EAA, and cesium with skin and blood EAA at birth. Overall, associations at birth did not persist in mid-childhood; however, arsenic was associated with greater EAA at birth and in childhood. Prenatal metals, including essential metals and arsenic, are associated with epigenetic aging in early life, which might be associated with future health.

Maternal fibrinogen/fibrin degradation products to high density lipoprotein cholesterol ratio for predicting delivery of small and large for gestational age infants: a pilot study

BACKGROUND

The purpose of this pilot study was to investigate associations between fibrinogen/fibrin degradation products (FDP) to high density lipoprotein-cholesterol (HDL-C) ratio (FHR) of mothers and the risk of delivering large/small for gestational age (LGA/SGA) infants and to evaluate the predictive power of FHR on LGA/SGA.

METHODS

This study retrospectively reviewed 11,657 consecutive women whose lipid profiles and FDP levels were investigated at the time of admission for delivery at a specialized hospital. The FHR was calculated, and perinatal outcomes, including clinical parameters, were analyzed.

RESULTS

The prevalence of SGA was 9% (n = 1034), and that of LGA was 15% (n = 1806) in this cohort study. FHR was significantly lower in women who delivered SGA infants (4.0 ± 3.2 vs. 4.7 ± 3.3 mg/mmol, P < 0.01) and higher in women who delivered LGA infants (5.7 ± 3.8 vs. 4.7 ± 3.3 mg/mmol, P < 0.01) compared with those who delivered infants of normal size for their gestational age. Women in the top quartile for FHR (> 5.9 mg/mmol) had a 2.9-fold higher risk of delivering LGA infants [adjusted odds ratio (OR) = 2.9, P < 0.01] and a 47% lower risk of delivering SGA infants (adjusted OR = 0.47, P < 0.01) than those in the bottom quartile (< 2.7 mg/mmol). In addition, adding FHR to the conventional models significantly improved the area under the curve for the prediction of delivering LGA (0.725 vs. 0.739, P < 0.01) and SGA (0.717 vs. 0.727, P < 0.01) infants.

CONCLUSION

These findings suggest that the FHR calculated in late pregnancy is an innovative predictor of delivering LGA and SGA infants. Combining FHR with perinatal parameters could thus enhance the predictive ability for predicting the delivery of LGA/SGA infants.

The Influence of Maternal Folate Status on Gestational Diabetes Mellitus: A Systematic Review and Meta-Analysis

Maternal folate has been shown to relate to the risk of gestational diabetes mellitus (GDM). However, the existing studies have yielded inconsistent conclusions. The purpose of this study was to systematically review the association between maternal folate status and the risk of GDM. Observational studies up to 31 October 2022 were included. Study characteristics, the means and standard deviations (SDs) of folate levels (serum/red blood cell (RBC)), the odds ratios (ORs) with 95% confidence intervals (CIs) and the time for folate measurement were extracted. Compared with the non-GDM group, serum and RBC folate levels in women with GDM were significantly higher. Our subgroup analysis demonstrated that serum folate levels in the GDM group were significantly higher than in the non-GDM group only in the second trimester. RBC folate levels in the GDM group were significantly higher than in the non-GDM group in the first and second trimesters. Taking serum/RBC folate levels as continuous variables, the adjusted odds ratios of GDM risk showed that increased serum folate concentration rather than RBC folate elevated the risk of GDM. In the descriptive analysis, five studies reported high serum folate levels increased GDM risk, whereas the other five showed no association between serum folate levels and GDM risk. Moreover, the rest three studies pointed out high RBC folate levels increased GDM risk. Altogether we found that the risk of GDM is associated with high serum/plasma and RBC folate levels. Future studies should determine the recommended folic acid cutoff balancing the risk for GDM and fetal malformations.

Platelet counts affect the association between hyperhomocysteinemia and pregnancy complications

BACKGROUND

The joint effect of platelet and other modifiers on the risk of pregnancy complications is unknown. This study investigated whether platelet count (PC) and total homocysteine (tHcy) level have a synergistic effect on the incidence of pregnancy complications in a Chinese population.

METHODS

Total 11,553 consecutive pregnant women who received whole blood cell and biochemical tests at the time of admission for labor in Changzhou Maternal and Child Health Care Hospital were analyzed. The primary outcome was the prevalence of pregnancy complications: gestational diabetes mellitus (GDM), intrahepatic cholestasis of pregnancy (ICP), pre-eclampsia (PE), and pregnancy induced hypertension (PIH).

RESULTS

The prevalence of GDM, ICP, PE, and PIH was 8.4%, 6.2%, 3.4%, and 2.1%, respectively. The highest rate of ICP (28.6%) was observed in women with high tHcy (> 15 μmol/L) and low PC (quartile 1); and the lowest rate of GDM (0.6%) was found in women with high tHcy and high PC (quartiles 2 to 4). In low PC group, the prevalence of ICP in women with high tHcy was significantly higher than that in women with low tHcy (≤ 15 μmol/L) (28.6% vs. 8.4%), representing an absolute risk increment of 20.2% and a relative risk increment of 3.3-fold (OR: 3.34; 95% CI: 1.55, 7.17; P = 0.002), whereas no joint effect was observed among high PC group.

CONCLUSIONS

Among Chinese pregnant women, one subgroup (high tHcy and low PC) has the highest risk of ICP and another (high tHcy and high PC) has the lowest risk of GDM; tHcy and platelet could be used as indicators to identify the women with high risk of ICP or low risk of GDM.

Plasma Homocysteine, Folic Acid and Vitamin B12 in Abruptio Placentae: A Cross-Sectional Study of Their Role and Feto-Maternal Outcome

Background Out of the many causes of abruptio placentae, the micronutrient association with its occurrence and severity has not been researched extensively till now. We aim to measure the serum levels of homocysteine, folic acid and vitamin B12 in patients with abruptio placentae in the third trimester of pregnancy and compare the levels with those without the complication. We also propose to compare the feto-maternal outcome between the groups. Methods The cross-sectional study was undertaken in 50 pregnant women with abruption before or during delivery and 50 controls with uncomplicated pregnancy over 28 weeks of gestation. Serum levels of homocysteine, folic acid, and vitamin B12 were determined and feto-maternal outcome was compared between the groups Results Mean age of the cases and controls are 26.82 ± 5.5 and 28.82 ± 4.88 years respectively. Obstetric characteristics have significant difference between the groups in terms of gravidity, mode of delivery, timing of delivery, proportion of stillbirths and blood transfusion. The mean concentration of homocysteine and vitamin B12 between the groups also have a significant difference . The serum level of homocysteine is significantly correlated with serum vitamin B12 level (Pearson correlation= -0.601, P=0.000). However, folic acid concentration between the groups remains comparable. Conclusion Hence we conclude that vitamin B12 and homocysteine are significant determinants of abruptio placentae in pregnant women. Supplementation with the vitamin in the high-risk Indian population can avert a number of obstetric complications occurring due to raised homocysteine.

Variation of vitamin B contents in maize inbred lines: Potential genetic resources for biofortification

Vitamin B and its derivatives possess diverse physiological functions and are essential micronutrients for humans. Their variation in crops is important for the identification of genetic resources used to develop new varieties with enhanced vitamin B. In this research, remarkable variations were observed in kernels of 156 maize inbred lines, ranging from 107.61 to 2654.54 μg per 100 g for vitamin B1, 1.19-37.37 μg per 100 g for B2, 19.60-213.75 μg per 100 g for B3, 43.47-590.86 μg per 100 g for B5, and 138.59-1065.11 μg per 100 g for B6. Growing inbreeds in Hainan and Hebei provinces of China revealed environmental and genotype interactions among these vitamins and the correlations between them in maize grain. Several inbred lines were identified as good sources of vitamin B and promising germplasms for maize breeding, namely By855 and Si273 are overall rich in all the studied vitamins, and GY386B and CML118 are specially enriched with derivatives of vitamin B6. The present study can assist maize breeders with germplasm resources of vitamin B for biofortification to offer people nutritious foods.