Maternal miscarriage history and risk of anencephaly

Determinants of neural tube defects among women who gave birth in hospitals in Eastern Ethiopia: evidence from a matched case control study

INTRODUCTION

Neural tube defects (NTDs) are severe birth defects caused by nutritional, genetic or environmental factors. Because NTDs continue to have a significant health and economic impact on children and community at large, it is crucial to investigate potential risk factors in order to develop novel approaches to NTDs prevention. Determinants for the development of NTDs differ by country, region as well as within the country. The objective of this study was to identify the determinants of NTDs among newborns delivered in three hospitals found in eastern Ethiopia.

METHODS

A hospital-based matched case-control study was conducted among 138 cases and 138 control women who delivered in three teaching hospitals in Eastern Ethiopia in 2021. Data were collected using a structured and pre-tested interviewer-administered questionnaire. Cases were mothers who delivered a neonate with any type of NTDs regardless of gestational age or fetal viability, whereas controls were mothers who delivered an apparently healthy newborn. Chi-square was used to assess the significant difference between the two groups. Conditional logistic regression model was used to generate adjusted odds ratio with its corresponding 95% confidence intervals and compare the two groups.

RESULTS

Anencephaly (51.4%) and spinal bifida (34.1%) were the most frequently observed NTDs. None of study participants took preconception folic acid supplementation. Being a non-formal mothers (AOR = 0.34, 95% CI: 0.12-0.92, P = 0.034), rural residence, (AOR = 3.4, 95% CI: 1.18-9.78, P = 0.023), history of spontaneous abortion (AOR = 2.95, 95% CI: 1.15-7.55, P = 0.023), having severe anemia (AOR = 3.4, 95% CI: 1.17-9.87, P = 0.024), history of fever or cold (AOR = 2.75; 95% CI: 1.05-7.15, P = 0.038), and an exposure to various agro-chemicals (AOR = 3.39, 95% CI: 1.11-10.3, P = 0.032) were independent determinants of NTDs.

CONCLUSION AND RECOMMENDATION

In this study, NTDs were associated to several determinant factors in the area, including residential area, history of spontaneous abortion, severe anemia, fever/cold, antibiotic use before or during early pregnancy, and exposure to agrochemicals. Addressing the identified determinants is critical in averting the incidence of NTDs in the study area. Moreover, more research is needed to investigate women's dietary practices as well as the practice of preconception folic acid supplementation for pregnant women in Ethiopia's current health care system.

Effect of periconceptional folic acid supplementation on the risk of neural tube defects associated with a previous spontaneous abortion or maternal first-trimester fever

STUDY QUESTION

Does maternal periconceptional no folic acid supplementation have an increased risk of neural tube defects (NTDs) associated with previous spontaneous abortion or first-trimester fever?

SUMMARY ANSWER

Maternal periconceptional no folic acid supplementation can increase the risk of NTDs associated with previous spontaneous abortion or first-trimester fever, independent of known confounding factors.

WHAT IS KNOWN ALREADY

Maternal periconceptional folic acid deficiency can increase the risk of NTDs. However, whether an interaction between periconceptional no folic acid supplementation and history of spontaneous abortion or first-trimester fever may have an increased risk of NTDs remains unknown.

STUDY DESIGN, SIZE, DURATION

A population-based case-control study was performed including 104 nuclear families with offspring with NTDs and 100 control families with normal offspring between 1993 and 2002.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We investigated the potential interaction between periconceptional no folic acid use and a maternal history of spontaneous abortion or first-trimester fever in the risk for NTDs. Information on exposure factors was obtained at the onset of pregnancy, and pregnancy outcomes were collected during the first week after delivery or at the time of termination of the pregnancy. A multivariate logistic regression analysis was performed.

MAIN RESULTS AND THE ROLE OF CHANCE

The interaction between periconceptional no folic acid use and a maternal history of spontaneous abortion markedly increased the risk of NTDs (adjusted odds ratio (aOR) 18.68, 95% CI, 4.43-78.76) after adjusting for potential confounding factors. The interaction coefficient was found to be 2.08, higher than 1, indicating that there is a significant interaction between two factors. Mothers who did not take periconceptional folic acid and had first-trimester fever had an increased risk of NTDs (aOR 21.81, 95% CI, 8.81-80.73). However, the interaction coefficient was found to be 0.62, less than 1, indicating that there is no significant interaction between two factors.

LIMITATIONS, REASONS FOR CAUTION

A potential limitation was that the interval between the previous spontaneous abortion and the beginning of the subsequent pregnancy could not be estimated accurately, but was at least 1 year or more.

WIDER IMPLICATIONS OF THE FINDINGS

We emphasize that a previous spontaneous abortion may represent a first occurrence of NTDs rather than be the cause of NTDs. Our findings indicate that mothers with a history of spontaneous abortion are ideal candidates for periconceptional folic acid supplementation.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by National Natural Science Foundation of China (41871360) and Danone Nutrition Center for Dietary Nutrition Research and Education Foundation (DIC2015-05). There are no competing interests to declare.

Maternal, paternal, and neonatal risk factors for neural tube defects: A systematic review and meta-analysis

OBJECTIVE

Neural tube defects [NTDs] are severe congenital anomalies. The etiology of NTDs is not fully known, and studies on the potential risk factors of NTDs present inconsistent results. Thus, we conducted a systematic review and meta-analysis to investigate the maternal, paternal, and neonatal risk factors for NTDs.

STUDY DESIGN

We systematically reviewed relative original studies published through October 6, 2018 available in Pubmed, Embase and the Cochrane Library without restrictions for language. The selected studies measured maternal, paternal, and neonatal risk factors and examined their associations with NTDs. A meta-analysis, including subgroup analysis and sensitivity analysis, was conducted to estimate the pooled effect measures. Two reviewers independently extracted data using a predesigned data collection form.

RESULTS

Forty-five studies were eligible for inclusion in the meta-analysis, and twelve potential risk factors were analyzed. The factors that were associated with NTDs risk included stressful life events [odds ratio [OR],1.61; 95% confidence interval [CI], 1.24-2.08; p < 0.001; I2 = 59.2%], low maternal education level [OR, 1.42; 95% CI, 1.19-1.70; p < 0.001; I2 = 47.7%], pregestational diabetes [OR, 2.24; 95% CI, 1.21-4.12; p < 0.010; I2 = 56.3%], low paternal age [OR, 1.41; 95% CI, 1.10-1.81; p = 0.007; I2 = 0.0%], low birth weight [OR, 5.53; 95% CI, 1.95-15.70; p = 0.001; I2 = 98.5%], and neonatal female gender [OR, 1.54; 95% CI, 1.10-2.14; p = 0.012; I2 = 67.8%].

CONCLUSION

Stressful life events, pregestational diabetes, low birth weight, and neonatal female gender are risk factors associated with NTDs. Low maternal education level and low paternal age are factors that are moderately associated with NTDs. Further cohort studies are required to verify the factors associated with NTDs and control the risk of this severe birth defect.

The association of maternal factors with epibulbar dermoid of newborn: a retrospective, matched case-control study

PurposeTo determine the association of maternal factors and exposure during pregnancy with the incidence in newborns of epibulbar dermoid (ED), a congenital ocular surface benign tumor.Patients and methodsThis is a retrospective, paired case-control study in which 121 children with ED (case group) and 121 children without ED (control group) were recruited. Questionnaire-based interviews with mothers of participants were performed and maternal medical records during pregnancy were reviewed. The questionnaire investigated basic information, personal history, environmental exposure, exposure to maternal diseases, symptoms and corresponding medical treatments during pregnancy, and parental socioeconomic status. The case and control participants were matched for sex, birth weight, gestational age, and parental socioeconomic status level. Univariate and multivariate logistic regression analyses were conducted with ED as the main outcome variable.ResultsFactors significantly associated with ED were: history of maternal inevitable miscarriage (odds ratio (OR), 2.59; 95% confidence intervals (CI), 1.13-5.90), common cold in the first trimester (OR, 3.94; CI, 1.74-8.93), and paternal smoke exposure >half a pack per day during pregnancy (OR, 4.81; CI, 1.74-13.28).ConclusionHistory of maternal miscarriage, common cold exposure in the first trimester, and paternal smoking (>half a pack per day) during pregnancy could result in significant risk factors for ED of newborns. These data also imply that paternal smoking delivers nicotine to maternal respiratory system and uterine microenvironment that may both affect microvascular development and predispose the fetus to future ED.

Amniotic fluid and serum biomarkers from women with neural tube defect-affected pregnancies: a case study for myelomeningocele and anencephaly: clinical article

OBJECT

The authors sought to identify novel biomarkers for early detection of neural tube defects (NTDs) in human fetuses.

METHODS

Amniotic fluid and serum were drawn from women in the second trimester of pregnancy. The study group included 2 women pregnant with normal fetuses and 4 with fetuses displaying myelomeningocele (n = 1), anencephaly (n = 1), holoprosencephaly (n = 1), or encephalocele (n = 1). Amniotic fluid stem cells (AFSCs) were isolated and cultured. The cells were immunostained for the stem cell markers Oct4, CD133, and Sox2; the epigenetic biomarkers H3K4me2, H3K4me3, H3K27me2, H3K27me3, H3K9Ac, and H3K18Ac; and the histone modifiers KDM6B (a histone H3K27 demethylase) and Gcn5 (a histone acetyltransferase). The levels of 2 markers for neural tube development, bone morphogenetic protein-4 (BMP4) and sonic hedgehog (Shh), were measured in amniotic fluid and serum using an enzyme-linked immunosorbent assay.

RESULTS

The AFSCs from the woman pregnant with a fetus affected by myelomeningocele had higher levels of H3K4me2, H3K4me3, H3K27me2, and H3K27me3 and lower levels of KDM6B than the AFSCs from the women with healthy fetuses. The levels of H3K9ac, H3K18ac, and Gcn5 were also decreased in the woman with the fetus exhibiting myelomeningocele. In AFSCs from the woman carrying an anencephalic fetus, levels of H3K27me3, along with those of H3K9Ac, H3K18ac, and Gcn5, were increased, while that of KDM6B was decreased. Compared with the normal controls, the levels of BMP4 in amniotic fluid and serum from the woman with a fetus with myelomeningocele were increased, whereas levels of Shh were increased in the woman pregnant with a fetus displaying anencephaly.

CONCLUSIONS

The levels of epigenetic marks, such as H3K4me, H3K27me3, H3K9Ac, and H3K18A, in cultured AFSCs in combination with levels of key developmental proteins, such as BMP4 and Shh, are potential biomarkers for early detection and identification of NTDs in amniotic fluid and maternal serum.

Is maternal parity an independent risk factor for birth defects?

BACKGROUND

Although associations between maternal parity and birth defects have been observed previously, few studies have focused on the possibility that parity is an independent risk factor for birth defects. We investigated the relation between levels of parity and a range of birth defects, adjusting each defect group for the same covariates.

METHODS

We included infants who had an estimated delivery date between 1997 and 2007 and participated in the National Birth Defects Prevention Study, a multisite case-control study. Cases included infants or fetuses belonging to 38 phenotypes of birth defects (n = 17,908), and controls included infants who were unaffected by a major birth defect (n = 7173). Odds ratios (ORs) were adjusted for 12 covariates using logistic regression.

RESULTS

Compared with primiparous mothers, nulliparous mothers were more likely to have infants with amniotic band sequence, hydrocephaly, esophageal atresia, hypospadias, limb reduction deficiencies, diaphragmatic hernia, omphalocele, gastroschisis, tetralogy of Fallot, and septal cardiac defects, with significant ORs (1.2 to 2.3). Compared with primiparous mothers, multiparous mothers had a significantly increased risk of omphalocele, with an OR of 1.5, but had significantly decreased risk of hypospadias and limb reduction deficiencies, with ORs of 0.77 and 0.77.

CONCLUSIONS

Nulliparity was associated with an increased risk of specific phenotypes of birth defects. Most of the phenotypes associated with nulliparity in this study were consistent with those identified by previous studies. Research into biologic or environmental factors that are associated with nulliparity may be helpful in explaining some or all of these associations.

Maternal reproductive history and the risk of isolated congenital malformations

We examined the relationship between maternal reproductive history and the newborn's risk of isolated congenital malformations in a large case-control cohort from the Polish Registry of Congenital Malformations. Congenital malformations were classified into four categories: isolated congenital heart defects (n=1673), isolated cleft palate (n=255), cleft lip with or without cleft palate (n=448) and renal agenesis (n=103). The case groups were compared with a shared group of 2068 controls recruited in the same time period and geographic area. Multivariable logistic regression was used to assess the risk associated with maternal gravidity and of previous miscarriages after accounting for maternal age and other potential risk factors. In unadjusted analyses, maternal gravidity was significantly associated with increased risk of all four classes of congenital malformations. After adjustment, a significant association persisted for congenital heart defects [odds ratio (OR)=1.22, [95% confidence interval (CI) 1.09, 1.36], P=0.0007] and cleft lip with or without cleft palate (OR=1.21, [95% CI 1.09, 1.36], P=0.0005). A similar trend existed for isolated cleft palate (OR=1.18, [95% CI 1.02, 1.37], P=0.03). There was no appreciable increase in the risk of congenital malformations associated with a maternal history of miscarriages, but a trend for a protective effect on the occurrence of cleft lip with or without cleft palate was observed (OR=0.72, [95% CI 0.52, 0.99], P=0.045). Based on our data, maternal gravidity represents a significant risk factor for congenital heart defects and cleft lip with or without cleft palate in the newborn infant. Our data do not support an increase in risk because of past history of miscarriages.