Lower Risk Of Small For Gestational Age Research Articles

Maternal Iodine Status and Birth Outcomes: A Systematic Literature Review and Meta-Analysis.

Background & aims: Iodine is important for thyroid function during pregnancy to support fetal growth, but studies of maternal iodine status and birth outcomes are conflicting. We aimed to quantify the association between iodine status and birth outcomes, including potential threshold effects using nonlinear dose−response curves. Methods: We systematically searched Medline and Embase to 10 October 2022 for relevant cohort studies. We conducted random-effects meta-analyses of urinary iodine concentration (UIC), iodine:creatinine ratio (I:Cr), and iodide intake for associations with birth weight, birth weight centile, small for gestational age (SGA), preterm delivery, and other birth outcomes. Study quality was assessed using the Newcastle-Ottawa scale. Results: Meta-analyses were conducted on 23 cohorts with 42269 participants. Birth weight was similar between UIC ≥ 150 μg/L and <150 μg/L (difference = 30 g, 95% CI −22 to 83, p = 0.3, n = 13, I2 = 89%) with no evidence of linear trend (4 g per 50 μg/L, −3 to 10, p = 0.2, n = 12, I2 = 80%). I:Cr was similar, but with nonlinear trend suggesting I:Cr up to 200 μg/g associated with increasing birthweight (p = 0.02, n = 5). Birthweight was 2.0 centiles (0.3 to 3.7, p = 0.02, n = 4, I2 = 0%) higher with UIC ≥ 150 μg/g, but not for I:Cr. UIC ≥ 150 μg/L was associated with lower risk of SGA (RR = 0.85, 0.75 to 0.96, p = 0.01, n = 13, I2 = 0%), but not with I:Cr. Conclusions: The main risk of bias was adjustment for confounding, with variation in urine sample collection and exposure definition. There were modest-sized associations between some measures of iodine status, birth weight, birth weight centile, and SGA. In pregnancy, we recommend that future studies report standardised measures of birth weight that take account of gestational age, such as birth weight centile and SGA. Whilst associations were modest-sized, we recommend maintaining iodine sufficiency in the population, especially for women of childbearing age on restricted diets low in iodide.

The gestational age-specific difference in birthweight between singletons born after fresh and frozen embryo transfer: A cohort study.

Accumulating studies have suggested singletons born after frozen embryo transfer (FET) were higher than those born after fresh embryo transfer (Fre-ET). However, fewer studies had investigated the gestational age-specific between-group difference in birthweight. This study aimed to investigate the gestational week-specific difference in singleton birthweight after FET vs Fre-ET and explore potential factors that impact the difference. In this retrospective cohort study, a total of 25 863 singletons were included. Multivariable linear regression and logistic regression were used to evaluate the between-group differences in mean birthweight and the incidences of large for gestational age (LGA) and small for gestational age (SGA), respectively. Multivariable regression analyses showed a statistically significant interaction between types of embryo transfer (ie FET vs Fre-ET) and the gestational week on mean birthweight (P < 0.001) and on the risks of large for gestational age (P=0.001) and small for gestational age (P < 0.001). When stratified by gestational week, the differences in mean birthweight and the risks of LGA and SGA were only observed in singletons born at 37 gestational weeks or later. After adjusting for confounders, full-term but not preterm singletons born after FET had a higher birthweight (3497.58 ± 439.73 g vs 3445.67 ± 450.24 g; adjusted mean difference 58.35 g; 95% confidence interval [CI] 38.72-77.98 g), a higher risk of LGA (24.3% vs 21.1%; adjusted odds ratio [OR] 1.28, 95% CI 1.15-1.42) and a lower risk of SGA (3.1% vs 4.8%; adjusted OR 0.61, 95% CI 0.53-0.70) compared with those born after Fre-ET. The differences in birthweight between FET and Fre-ET were observed in full-term singletons but not preterm singletons.

Dietary patterns before and during pregnancy and small for gestational age in Japan: a prospective birth cohort study

BackgroundAlthough small for gestational age (SGA) is a serious problem worldwide, the association of dietary patterns before and during pregnancy with SGA risk is unclear. We evaluated this association among Japanese pregnant women using three methods: reduced rank regression (RRR) and partial least squares (PLS), methods for extracting dietary patterns that can explain the variation of response variables, and principal component analysis (PCA), a method for extracting dietary patterns of the population.MethodsBetween July 2013 and March 2017, 22,493 pregnant women were recruited to the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study, a population-based prospective birth cohort study in Japan. Information on dietary intake was obtained using food frequency questionnaires, and dietary patterns were extracted using RRR, PLS, and PCA. Information on birth weight was obtained from obstetric records, and the birth weight SD score and SGA were defined by the method of the Japan Pediatric Society. The associations of dietary patterns with birth weight SD score and SGA risk were investigated using multiple linear regression and multiple logistic regression, respectively.ResultsA total of 17,728 mother-child pairs were included. The birth weight SD score was 0.15 ± 0.96, and the prevalence of SGA was 6.3%. The dietary patterns extracted by RRR and PLS were similar and characterized by a high intake of cereals and fruits and a low intake of alcoholic and non-alcoholic beverages in both pre- to early pregnancy and from early to mid-pregnancy. Higher adoption of the RRR and PLS patterns in both periods was associated with an increased birth weight SD score and lower risk of SGA. In contrast, the PCA1 pattern was not associated with birth weight SD score or SGA risk in either period. Although the PCA2 pattern was associated with increased birth weight SD score from early to mid-pregnancy, no other associations with birth weight SD score or SGA risk were observed.ConclusionsThe dietary pattern with a high intake of cereals and fruits and a low intake of alcoholic and non-alcoholic beverages before and during pregnancy was associated with a decreased SGA risk in Japan.

P-749 How do different uterine anomalies compare for pregnancy complications? An evaluation of a large American population database

Abstract Study question What type of uterine anomalies cause alterations in pregnancy complications, compared to other anomalies, based on analysis of the Healthcare-Cost and Utilization-Project-Nationwide Inpatient Sample(HCUP-NIS) database? Summary answer After controlling for confounders, bicornuate uteri had lower risks and arcuate uteri had increased risks of cesareans and mostly similar risks of other outcomes. What is known already Women with mullerian anomalies are known to have increased risks of adverse obstetrical outcomes. Comparison of different adverse obstetrics outcomes between women with different type of uterine anomalies has minimally been studied. Study design, size, duration This retrospective population-based cohort study utilized data from the HCUP-NIS from 2010-2014, inclusively. A cohort of all deliveries during the study period was created. Within this group, Six thousand and one hundred ninety-five deliveries were to women with bicornuate uteri, 798 were to women with arcuate uteri, 2255 were in women with didelphys uteri, 802 were from women with unicornuate uteri and 1404 were deliveries to women with septate uteri. Participants/materials, setting, methods HCUP-NIS is the largest inpatient sample database in the USA and is comprised of hospital stays throughout the country. It provides information relating to seven million inpatient stays yearly, includes 20% of admissions, and represents over 96% of the American population. Multivariate logistic regression was conducted to explore associations between uterine anomalies and delivery outcomes. According to the Tri-Council Policy Statement (2018), IRB approval was not required, given data was anonymous and publicly available. Main results and the role of chance After adjustment for confounders, women with bicornuate uteri had less risk for chorioamnionitis(aOR:0.6, 95%CI:0.5-0.8-P=0.003), were more likely to deliver vaginally or by operative vaginal delivery(aOR:1.4, 95%CI:1.1-1.9-P=0.01), and less likely to deliver by CD when compared to the other anomalies(aOR:0.6, 95%CI:0.5-0.6-P=0.0001). They had lower risk of SGA (small for gestational age)(aOR:0.8, 95%CI:0.7-0.9-P=0.03). Pregnant women with arcuate uterus had lower risk of preterm delivery compared to the other anomalies(aOR:0.6, 95%CI:0.5-0.8-P=0.0001), less chance of having delivered by an operative vaginal delivery(aOR:0.5, 95%CI:0.2-0.9-P=0.04), and were at higher risk of having a CD(aOR:1.6, 95%CI:1.4-2-P=0.0001). Pregnant women with didelphys uteri had higher risk of PPROM(aOR:1.6, 95%CI:1.3-1.9-P=0.0001), preterm delivery(aOR:1.5, 95%CI:1.3-1.6-P=0.0001), CD(aOR:1.4, 95%CI:1.2-1.5-P=0.0001) and wound complications(aOR:1.6, 95%CI:1.1-2.4-P=0.02) compared to the other anomalies. However, they had less risk for placenta abruptia(aOR:0.6, 95%CI:0.5-0.9-P=0.02). Pregnant women with unicornuate uteri had increased risks of preterm delivery(aOR:1.4, 95%CI:1.1-1.6-P=0.0001), CD(aOR:3.0, 95%%CI:1.6-2.5-P=0.0001) and SGA(aOR:1.8, 95%CI:1.4-2.3-P=0.0001) with lower risk of placenta abruptia(aOR:0.5, 95%CI:0.3-0.9-P=0.03). Pregnant women with septate uteri had higher risk of chorioamnionitis(aOR:1.5, 95%CI:1.1-2.1-P=0.048) and CD(aOR:1.4, 95%CI: 1.2-1.6-P=0.0001). Other pregnancy complications studied which included PPH, the need for hysterectomy, and IUFD had similar rates between the groups(p &amp;gt; 0.05 all). Limitations, reasons for caution This is a retrospective analysis utilizing an administrative database that relies on data coding accuracy and consistency Wider implications of the findings There are different risks for certain adverse pregnancy and neonatal outcomes in different uterine anomalies as compared to the other anomalies. Although, regarding many pregnancy complications, risks were similar with different anomalies. Arcuate uterus mostly responds in a similar manner in terms of pregnancy complications as other anomalies. Trial registration number NA

Association of Maternal Longitudinal Hemoglobin with Small for Gestational Age during Pregnancy: A Prospective Cohort Study.

Background: Few studies have investigated the association of maternal longitudinal hemoglobin (Hb) with small for gestational age during pregnancy. The current study examined the associations of maternal Hb concentrations and Hb changes throughout the middle and late stages of pregnancy with small for gestational age (SGA) in a large prospective cohort study. Methods: This was a prospective cohort study, which enrolled pregnant women at 8–16 weeks of gestation and followed up regularly. Maternal Hb concentrations were measured at the middle (14–27 weeks) and late (28–42 weeks) stages of pregnancy, and the Hb change from the middle to late stage of pregnancy was assessed. The Log-Poisson regression model was used to identify the association of maternal Hb with SGA, including the implications of Hb during specific pregnancy periods and Hb change across the middle to late stages of pregnancy. Of the total 3233 singleton live births, 208 (6.4%) were SGA. After adjusting for potential confounders, compared with Hb 110–119 g/L, Hb ≥ 130 g/L at late pregnancy was significantly associated with a higher risk of SGA (adjusted RR: 2.16; 95% CI: 1.49, 3.13). When Hb changes from the middle to late stages of pregnancy were classified by tertiles, the greatest change in the Hb group (<−6.0 g/L) was significantly associated with a lower risk of SGA (adjusted RR: 0.56; 95% CI: 0.37, 0.85) compared with the intermediate group (−6.0~1.9 g/L). In conclusion, for women at low risk of iron deficiency, both higher Hb concentrations in late pregnancy and less Hb reduction during pregnancy were associated with an increased risk of SGA.

Gestational weight gain rates in the first and second trimesters are associated with small for gestational age among underweight women: a prospective birth cohort study

BackgroundDespite the well-studied effects of gestational weight gain (GWG) on offspring health, little is known about the association of trimester-specific GWG with offspring birth weight among underweight pregnant women. This study aimed to explore the association of trimester-specific GWG rate with small for gestational age (SGA) in underweight women.MethodsThe GWG rate of underweight pregnant women (pre-pregnancy body mass index [BMI] lower than 18.5 kg/m2) of the Born in Guangzhou Cohort Study was calculated as the weight gain during a specific trimester divided by the corresponding duration of week. Total GWG was calculated as the weight difference between pre-pregnancy and delivery, and was categorized into inadequate, adequate, and excessive weight gain based on the 2009 Institute of Medicine (IOM) weight gain recommendation. The INTERGROWTH-21st standards were used to define SGA. Logistic regression models were used to examine the associations of total GWG and trimester-specific GWG rates with SGA. Associations between trimester-specific GWG rates and SGA were also analyzed separately based on different total GWG categories (i.e. inadequate and adequate/excessive GWG).ResultsOf the 3839 participants, SGA births occurred in 397 (10.3%), and mean GWG was 14.9 kg (SD 3.9). A lower risk of SGA was observed among women with higher GWG rate (per 0.5 kg/week increase) during the first (adjusted OR [aOR] 0.74, 95%CI 0.57, 0.96) and second (adjusted OR [aOR] 0.40, 95%CI 0.30, 0.55) but not third trimester. Similar association between higher GWG rate during the second trimester and a decreased risk of SGA were observed among women with inadequate (< 12.5 kg) and adequate/excessive (≥12.5 kg) total GWG, respectively. Compared to women with adequate GWG rate, women with inadequate GWG rate during the second trimester had a significantly increased risk of SGA (aOR 1.58, 95% CI 1.14, 2.20).ConclusionsSecond-trimester GWG might be the key driver for the association between inadequate GWG and increased risk of SGA births in underweight women.

Association of maternal dietary patterns during pregnancy with small-for-gestational-age infants: Korean Mothers and Children’s Environmental Health (MOCEH) study

Nutrients that support the desired growth and development of the fetus (i.e., micronutrients like folate, iron, and zinc) have been associated with birth outcomes, such as gestational age at delivery and birth weight. We characterized the maternal dietary patterns that explain the maximum variation in folate, iron, and zinc intakes in pregnant Korean women using reduced-rank regression (RRR) and investigated the association of these patterns with small-for-gestational-age (SGA) risk. A total of 1158 pregnant Korean women at 12-28 weeks of gestation and their newborns were recruited for the Mothers and Children's Environmental Health (MOCEH) study between 2006 and 2010. A semiquantitative FFQ was collected from the women, and RRR was used to derive their dietary patterns. Log-transformed maternal intakes of folate, iron, and zinc were selected as the intermediate response variables to extract dietary patterns. Infant birth outcome measurements were obtained from hospital records. Associations were assessed by logistic regression with adjustment for confounding factors. Three dietary patterns were identified. Pattern 1, characterized by high intakes of grains, green/yellow and light-colored vegetables, kimchi, legumes, fruits, meat, eggs, fish, seaweeds, tofu/soymilk, yogurt, and nuts, was associated with a lower risk of SGA in the highest quartile than in the lowest quartile (OR: 0.36; 95% CI: 0.14, 0.94). Especially, maternal dietary pattern 1 was negatively related to high-sensitivity C-reactive protein in the blood and malondialdehyde concentrations in the urine. No association was observed between other dietary patterns and SGA. Among pregnant Korean women, adherence to a dietary pattern characterized by high intakes of grains, green/yellow and light-colored vegetables, kimchi, legumes, fruits, meat, eggs, fish, seaweeds, tofu/soymilk, yogurt, and nuts is associated with a lower risk of delivering SGA infants.

Associations of B Vitamin-Related Dietary Pattern during Pregnancy with Birth Outcomes: A Population-Based Study in Northwest China.

This study aimed to derive a maternal dietary pattern to explain the variation in B vitamins during pregnancy and to investigate this pattern in relation to birth outcomes. A total of 7347 women who gave birth to live newborns less than one year were included. Their dietary pattern during pregnancy was derived using the reduced-rank regression method with six B vitamins as response variables. Associations between dietary pattern score and birth weight, gestational age at delivery, birth weight Z score, low birth weight, preterm, and small-for-gestational-age (SGA) were estimated using generalised linear mixed models. We identified a high B-vitamin dietary pattern characterised by high intakes of animal foods, vegetables, fungi and algae, legumes, and low intakes of oils and cereals. Women in the highest quartile of this pattern score had newborns with a 44.5 g (95% CI: 13.8, 75.2 g) higher birth weight, 0.101 (95% CI: 0.029, 0.172) higher birth weight Z score, and 27.2% (OR: 0.728; 95% CI: 0.582, 0.910) lower risk of SGA than those in the lowest quartile. Our study suggested that adherence to the high B-vitamin dietary pattern during pregnancy was associated with a higher birth weight and a lower risk of SGA.

Impact of mode of conception on early pregnancy human chorionic gonadotropin rise and birth weight

ObjectiveTo assess whether the mode of conception and embryo biopsy impact first-trimester human chorionic gonadotropin (hCG) dynamics and subsequent risk of small for gestational age (SGA) or large for gestational age (LGA).DesignRetrospective cohort study.SettingUniversity fertility center.Patient(s)Six hundred-two pregnant patients with singleton live births.Intervention(s)Serial serum hCG measurements were obtained between 10 and 28 days postconception to determine the within-woman rate of change in hCG (slope) by mode of conception (unassisted pregnancy, fresh embryo transfer (ET), frozen ET, and frozen ET following preimplantation genetic testing for aneuploidy (PGT-A).Main Outcome Measure(s)Primary outcomes included birth weight, SGA, and LGA.Result(s)Mode of conception is not independently associated with birth weight, SGA, or LGA. Mediation analysis revealed an expected one-day increase in log-transformed hCG varied by mode of conception: unassisted (0.41), fresh ET (0.39), frozen ET (0.42), PGT-A (0.44). Human chorionic gonadotropin rise has a positive effect on birth weight (55 g per SD increase in hCG slope) and is associated with SGA (odds ratio, 0.65), but not with LGA (odds ratio, 1.18).Conclusion(s)Human chorionic gonadotropin rise is an important mediator of the mode of conception/birth weight relationship. Preimplantation genetic testing for aneuploidy has the highest rate of hCG rise, followed by frozen ET, unassisted, and fresh ET. Faster rise is associated with higher birth weight and lower risk of SGA but does not impact LGA risk. Importantly, PGT-A does not increase the risk of extreme birth weight relative to other modes of conception evaluated.

Moderate Freshwater Fish Intake, but Not n-3 Polyunsaturated Fatty Acids, Is Associated with a Reduced Risk of Small for Gestational Age in a Prospective Cohort of Chinese Pregnant Women

BackgroundAlthough previous studies have found that maternal fish intake is associated with fetal growth, the role of freshwater fish intake remains unknown. ObjectiveOur aim was to examine the relationships of freshwater fish and n-3 polyunsaturated fatty acids (PUFAs) intake with the risk of small for gestational age (SGA) in Chinese pregnant women. DesignThis was a prospective analysis of data from the Tongji Birth cohort in Wuhan, China, from 2018 to 2021. Participants/settingsThis study included 1,701 pregnant women who had completed a food frequency questionnaire dietary assessment during mid-pregnancy. Main outcome measuresIntake of fish was assessed by a semi-quantitative food frequency questionnaire. Total intake of n-3 PUFAs was the sum of data collected from both dietary and supplemental sources of n-3 PUFAs. Birth information was extracted from medical records. Statistical analysesMultivariate logistic regression models were applied to estimate odds ratios and 95% CIs. ResultsThe median (interquartile range) intake of freshwater fish and total n-3 PUFAs was 12.1 (4.3 to 26.4) g/d and 68.2 (24.5 to 370.0) mg/d, respectively. Moderate intake of freshwater fish was associated with reduced risk of SGA. Compared with the lowest quintile (0–3.2 g/d), the multivariable-adjusted odds ratio for women in the fourth quintile of freshwater fish intake (17.9 to 30.0 g/d) was 0.50 (95% CI 0.25 to 0.96). We found a nonlinear association between freshwater fish intake and SGA risk (Pnonlinearity = .027). However, maternal n-3 PUFAs intake was not significantly associated with SGA risk, either from total intake or from dietary sources alone. ConclusionsModerate freshwater fish intake during pregnancy is associated with lower risk of SGA in a Chinese population. This finding provides supportive evidence for freshwater fish intake during pregnancy, particularly for the inland areas of developing countries.

P–775 Obstetric and perinatal outcomes of singleton pregnancies after blastocyst-stage embryo transfer: a systematic review and cumulative meta-analysis

Abstract Study question Are obstetric/perinatal outcomes different in singleton pregnancies following blastocyst-stage embryo transfer when compared to cleavage-stage embryo transfer and have results changed over time? Summary answer Pregnancies following blastocyst are consistently associated with higher risk of large for gestational age and lower risk of small for gestational age babies What is known already Extended embryo culture to blastocyst-stage is widely used to select best embryos in in vitro fertilisation (IVF) cycles to improve pregnancy rates. Transfer of blastocyst-stage embryos is increasing with this being the default strategy in most clinics. As blastocysts are kept in culture until day 5, 6 or 7 after oocyte fertilisation, there are suggestions that longer exposure to culture media may have a negative impact on pregnancy outcomes. More recent primary studies have challenged some of the initial findings. We therefore conducted an updated systematic review and cumulative meta-analysis (CMA) to examine if these results have changed over time. Study design, size, duration Systematic review of studies published between 1980 and 2020, followed by aggregated meta-analysis and CMA to track the accumulation of evidence over the period of time. Exposed group: singleton pregnancies following blastocyst transfer. Non-exposed group: singleton pregnancies following cleavage-stage transfer. Sub-group analyses were conducted on fresh and frozen-thawed embryo transfers. Perinatal (categories of preterm birth and birth weight) and obstetric outcomes (hypertensive disorders of pregnancy, gestational diabetes, c-section, placental anomalies) were compared between the groups. Participants/materials, setting, methods Medline, EMBASE, CINHAL, Web of Science, Cochrane Central Register of Clinical Trials and International Clinical Trials Registry Platform databases were searched. Relevant journals were searched for advance access publications. Critical Appraisal Skills Programme (CASP) checklists were used to assess study quality. Two independent reviewers extracted data in 2 × 2 tables. Aggregated and CMA were performed using Comprehensive Meta-Analysis software. Risk ratio (RR) with 95% confidence interval (CI) were calculated. Main results and the role of chance A total of 33 observational studies were included (n = 574,756 singleton pregnancies). Pregnancies following blastocyst-stage embryo transfer are associated with a higher risk of preterm birth (PTB) (RR 1.09; 95% CI 1.01–1.17), very preterm birth (VPTB) (RR 1.15; 95% CI 1.07–1.24), large for gestational age (LGA) babies (RR 1.13; 95% CI 1.08–1.19), c-section (RR 1.05; 95% CI 1.02–1.09), and with a lower risk of small for gestational age (SGA) babies (RR 0.86; 95% CI 0.81–0.93) as compared to singleton pregnancies following cleavage-stage embryo transfer. These findings were maintained in both fresh and frozen-thawed sub-groups for LGA and SGA. PTB was not significantly different in both sub-group analyses. The risk of VPTB was higher after blastocyst-stage embryo transfer only in the sub-group analysis of fresh embryo transfers (RR 1.17; 95% CI 1.09–1.27) and that of c-section only in the frozen-thawed sub-group (RR 1.08; 95% CI 1.04–1.12). No other statistically significant differences for the other outcomes were noted. The CMA suggests that for SGA and LGA subsequent studies have increased the precision of the point estimate with no change in the direction or magnitude of the treatment effect since 2014. Limitations, reasons for caution This analysis was constrained by the intrinsic limitations of observational studies with some of them receiving a CASP score &amp;lt; 10. Adjustment for confounders was not possible and a high degree of clinical and statistical heterogeneity was noted among studies. Wider implications of the findings: Blastocyst is associated with a higher risk of LGA and a lower risk of SGA with a stable body of evidence since 2014. We may need to revisit the default position of extending embryo culture and individualise care, until further high-quality data from individual-patient-data of large registries are available. Trial registration number Not applicable

Parity and the risks of adverse birth outcomes: a retrospective study among Chinese

BackgroundNulliparity is considered to be a risk factor of preterm birth (PTB), low birth weight (LBW) and small for gestational age (SGA). With the new two-child policy launched in 2016, more Chinese women have delivered their 2nd baby. Yet few studies have assessed the impact of parity on adverse birth outcomes in China. This study aimed to examine the association between parity and risks of PTB, LBW and SGA in a Chinese population. The combined effects of maternal age and parity on adverse birth outcomes were also assessed.MethodsThis retrospective study included all non-malformed live births born during January 1, 2014 and December 31, 2018 in Chengdu, China. A total of 746,410 eligible live singletons with complete information were included in the analysis. Parity was classified into nulliparity (i.e. has never delivered a newborn before) and multiparity (i.e. has delivered at least one newborn before). Log-binomial regression analyses were applied to evaluate the association between parity and PTB, LBW and SGA. We further divided maternal age into different groups (< 25 years, 25–29 years, 30–34 years and ≥ 35 years) to assess the combined effects of maternal age and parity on adverse birth outcomes.ResultsMultiparity was associated with reduced risks of PTB (aRR = 0.91, 95% CI: 0.89–0.93), LBW (aRR = 0.74, 95% CI: 0.72–0.77) and SGA (aRR = 0.67, 95% CI: 0.66–0.69) compared with nulliparity. In each age group, we observed that multiparity was associated with lower risks of adverse birth outcomes. Compared to nulliparous women aged between 25 and 29 years, women aged ≥35 years had greater risks of PTB and LBW, regardless of their parity status. In contrast, multiparous women aged ≥35 years (aRR = 0.73, 95% CI: 0.70–0.77) and those aged < 25 years (aRR = 0.88, 95% CI: 0.84–0.93) were at lower risk of SGA compared with nulliparous women aged between 25 and 29 years.ConclusionMultiparity was associated with lower risks of all adverse birth outcomes. Special attention should be paid to nulliparous mothers and those with advanced age during antenatal care, in order to reduce the risks of adverse birth outcomes.

Maternal Dietary Selenium Intake during Pregnancy Is Associated with Higher Birth Weight and Lower Risk of Small for Gestational Age Births in the Norwegian Mother, Father and Child Cohort Study.

Selenium is an essential trace element involved in the body’s redox reactions. Low selenium intake during pregnancy has been associated with low birth weight and an increased risk of children being born small for gestational age (SGA). Based on data from the Norwegian Mother, Father and Child Cohort Study (MoBa) and the Medical Birth Registry of Norway (MBRN), we studied the association of maternal selenium intake from diet and supplements during the first half of pregnancy (n = 71,728 women) and selenium status in mid-pregnancy (n = 2628 women) with birth weight and SGA status, according to population-based, ultrasound-based and customized growth standards. An increase of one standard deviation of maternal dietary selenium intake was associated with increased birth weight z-scores (ß = 0.027, 95% CI: 0.007, 0.041) and lower SGA risk (OR = 0.91, 95% CI 0.86, 0.97) after adjusting for confounders. Maternal organic and inorganic selenium intake from supplements as well as whole blood selenium concentration were not associated with birth weight or SGA. Our results suggest that a maternal diet rich in selenium during pregnancy may be beneficial for foetal growth. However, the effect estimates were small and further studies are needed to elucidate the potential impact of selenium on foetal growth.

Maternal dietary diversity and dietary quality scores in relation to adverse birth outcomes in Tanzanian women

Preterm birth (PTB), small for gestational age (SGA), and low birth weight (LBW) are risk factors for morbidity and mortality among infants. High-quality maternal diets during pregnancy may protect against these adverse birth outcomes. The aim of this study was to prospectively examine the association of maternal dietary diversity and quality during pregnancy with birth outcomes among women in Dar es Salaam, Tanzania. We analyzed data from 7553 HIV-negative pregnant women enrolled in a multivitamin trial at 12-27 weeks of gestation. Dietary intake was assessed using 24-h dietary recalls. Dietary diversity scores (DDS; range: 0-10) were computed as the number of food groups consumed by women, using FAO's Minimum Dietary Diversity for Women index. The Prime Diet Quality Score (PDQS; range: 0-42) assessed maternal diet quality based on consumption of 21 healthy and unhealthy food groups. Log binomial regression methods were used to assess associations of DDS and PDQS with PTB, SGA, LBW, and fetal loss. In the previous 24 h, 99.9% of all women had consumed cereal and staples, 57.9% meats, 4.7% eggs, and 0.5% nuts and seeds. Median DDS was 3.0 (IQR: 2.5-3.5). For the PDQS, all women consumed ≥4 servings/wk of green leafy vegetables and refined grains. Higher DDS was associated with lower risk of SGA (RR highest compared with lowest quintile: 0.74; 95% CI: 0.62, 0.89). Higher PDQS was associated with lower risk of PTB (RR highest compared with lowest quintile: 0.55; 95% CI: 0.46, 0.66), LBW (RR: 0.53; 95% CI: 0.40, 0.70), and fetal loss (RR: 0.53; 95% CI, 0.34, 0.82). PDQS was inversely associated with PTB, LBW, and fetal loss, and DDS was inversely associated with SGA. These findings suggest that in addition to dietary diversity, diet quality should be considered as important in understanding dietary risk factors for poor birth outcomes.This trial was registered at clinicaltrials.gov as NCT00197548.

Maternal Dietary Diversity and Dietary Quality Scores in Relation to Adverse Birth Outcomes in Tanzanian Women

Abstract Objectives Preterm birth, small for gestational age (SGA) and low birth weight (LBW) are risk factors for morbidity and mortality among infants. High-quality maternal diets during pregnancy may protect against these adverse birth outcomes. The objective of this research is to prospectively examine the association of maternal dietary diversity and quality during pregnancy with birth outcomes among women in Dar es Salaam, Tanzania. Methods We analyzed data from 7553 HIV-negative pregnant women enrolled in a multivitamin trial at 12–27 weeks gestation. Dietary intake was assessed using 24-hour dietary recalls. Log binomial regression methods were used to assess associations of Minimum Dietary Diversity for Women (MDD-W) and Prime Diet Quality Score (PDQS) with preterm, SGA, LBW, fetal loss, very preterm, severe SGA and very low birth weight (VLBW). Results In the previous 24 hours, 99.9% of women reported consuming grains, roots and tubers, 57.9% meats, 4.7% eggs and 0.5% nuts and seeds. Median MDD-W score was 3.0 ± 1.0. For the PDQS, women consumed at least 4 servings/week of green leafy vegetables (100%) and other vegetables (64.7%) and consumption of refined grains was high (99.6%). Higher MDD-W scores were associated with lower risk of SGA (RR highest vs. lowest quintile 0.74, 95% CI: 0.62, 0.89). Higher PDQS scores were associated with lower risk of preterm birth (RR: 0.55, 95% CI: 0.46, 0.67); LBW (RR: 0.53, 95% CI: 0.40, 0.71); fetal loss (RR: 0.53, 95% CI: 0.34,0.82), very preterm (RR: 0.33, 95% CI: 0.17, 0.64) and VLBW (RR: 0.49, 95% CI: 0.26, 0.92) comparing women in highest vs. lowest quintiles. Conclusions PDQS was inversely associated with preterm, very preterm, LBW, VLBW and fetal loss, and MDD-W was inversely associated with SGA. These findings suggest that in addition to diet diversity, diet quality should be considered as important in understanding dietary risk factors for poor birth outcomes. Funding Sources This work has been supported by the National Institutes of Child Health and Human Development. Co-authors were supported by a grant from the National Institute of Child Health and Human Development and the National Institutes of Health.

Association of maternal thyroid function with birthweight: a systematic review and individual-participant data meta-analysis

Adequate transplacental passage of maternal thyroid hormone is important for normal fetal growth and development. Maternal overt hypothyroidism and hyperthyroidism are associated with low birthweight, but important knowledge gaps remain regarding the effect of subclinical thyroid function test abnormalities on birthweight-both in general and during the late second and third trimester of pregnancy. The aim of this study was to examine associations of maternal thyroid function with birthweight. In this systematic review and individual-participant data meta-analysis, we searched MEDLINE (Ovid), Embase, Web of Science, the Cochrane Central Register of Controlled Trials, and Google Scholar from inception to Oct 15, 2019, for prospective cohort studies with data on maternal thyroid function during pregnancy and birthweight, and we issued open invitations to identify study authors to join the Consortium on Thyroid and Pregnancy. We excluded participants with multiple pregnancies, in-vitro fertilisation, pre-existing thyroid disease or thyroid medication usage, miscarriages, and stillbirths. The main outcomes assessed were small for gestational age (SGA) neonates, large for gestational age neonates, and newborn birthweight. We analysed individual-participant data using mixed-effects regression models adjusting for maternal age, BMI, ethnicity, smoking, parity, gestational age at blood sampling, fetal sex, and gestational age at birth. The study protocol was pre-registered at the International Prospective Register of Systematic Reviews, CRD42016043496. We identified 2526 published reports, from which 36 cohorts met the inclusion criteria. The study authors for 15 of these cohorts agreed to participate, and five more unpublished datasets were added, giving a study population of 48 145 mother-child pairs after exclusions, of whom 1275 (3·1%) had subclinical hypothyroidism (increased thyroid stimulating hormone [TSH] with normal free thyroxine [FT4]) and 929 (2·2%) had isolated hypothyroxinaemia (decreased FT4 with normal TSH). Maternal subclinical hypothyroidism was associated with a higher risk of SGA than was euthyroidism (11·8% vs 10·0%; adjusted risk difference 2·43%, 95% CI 0·43 to 4·81; odds ratio [OR] 1·24, 1·04 to 1·48; p=0·015) and lower mean birthweight (mean difference -38 g, -61 to -15; p=0·0015), with a higher effect estimate for measurement in the third trimester than in the first or second. Isolated hypothyroxinaemia was associated with a lower risk of SGA than was euthyroidism (7·3% vs 10·0%, adjusted risk difference -2·91, -4·49 to -0·88; OR 0·70, 0·55 to 0·91; p=0·0073) and higher mean birthweight (mean difference 45 g, 18 to 73; p=0·0012). Each 1 SD increase in maternal TSH concentration was associated with a 6 g lower birthweight (-10 to -2; p=0·0030), with higher effect estimates in women who were thyroid peroxidase antibody positive than for women who were negative (pinteraction=0·10). Each 1 SD increase in FT4 concentration was associated with a 21 g lower birthweight (-25 to -17; p<0·0001), with a higher effect estimate for measurement in the third trimester than the first or second. Maternal subclinical hypothyroidism in pregnancy is associated with a higher risk of SGA and lower birthweight, whereas isolated hypothyroxinaemia is associated with lower risk of SGA and higher birthweight. There was an inverse, dose-response association of maternal TSH and FT4 (even within the normal range) with birthweight. These results advance our understanding of the complex relationships between maternal thyroid function and fetal outcomes, and they should prompt careful consideration of potential risks and benefits of levothyroxine therapy during pregnancy. Netherlands Organization for Scientific Research (grant 401.16.020).

Intake of dairy protein during pregnancy in IBD and risk of SGA in a Norwegian population-based mother and child cohort

BackgroundPatients with inflammatory bowel disease (IBD) tend to avoid dairy products to minimize abdominal pain and diarrhea. The aim of this study was to estimate the proportion of protein from dairy sources (PPDS) in mothers with and without IBD, and to explore the impact of PPDS on inadequate gestational weight gain (GWG) or small for gestational age (SGA) in IBD compared to non-IBD in the population-based Norwegian Mother, Father and Child Cohort Study (MoBa).MethodsMoBa includes about 95,000 pregnant women recruited throughout Norway from 1999 to 2008. IBD phenotype and complications during pregnancy and delivery were ascertained. This study included 148 mothers with Crohn disease (CD) and 194 with ulcerative colitis and 68,858 non-IBD mothers. In mid-pregnancy participants answered a comprehensive semi-quantitative food frequency questionnaire assessing diet since the start of pregnancy. PPDS was ranked in quartiles. The two lowest quartiles were merged and considered to represent the lowest of three PPDS groups. We used logistic regression analyses to model multivariate associations, adjusting for potential confounders.ResultsThe risk of belonging to the lowest PPDS group was twice as high in IBD mothers compared to non-IBD mothers (aOR = 2.02, 95% CI: 1.53, 2.67). Low compared to high PPDS strongly predicted inadequate GWG in CD (aOR = 4.22, 95% CI: 1.28, 13.92). Surprisingly, and in opposition to the non-IBD mothers, PPDS was positively associated with the risk of SGA in IBD mothers. IBD mother with low PPDS was associated with significantly lower risk of SGA than non-IBD mothers and IBD mothers with high PPDS (aOR = 0.19, 95% CI: 0.07, 0.50). The interaction term IBD/PPDS was the factor that linked SGA to IBD compared to non-IBD, and increased the association between IBD and SGA with a factor of three.ConclusionThis study shows that intake of dairy products is lower in IBD mothers than in non-IBD mothers, and further, that low intake of dairy products in IBD mothers is associated with reduced risk of SGA compared to non-IBD and IBD mothers with high PPDS.

Effects of maternal diets on preterm birth and low birth weight: a systematic review.

Current evidence indicates that maternal diets before and during pregnancy could influence rates of preterm birth, low birth weight (LBW) and small for gestational age (SGA) births. However, findings have been inconsistent. This review summarised evidence concerning the effects of maternal diets before and during pregnancy on preterm birth, LBW and SGA. Systematic electronic database searches were carried out using PubMed, Embase, Scopus and Cochrane library using the preferred reporting items for systematic reviews and meta-analyses guidelines. The review included forty eligible articles, comprising mostly of prospective cohort studies, with five randomised controlled trials. The dietary patterns during pregnancy associated with a lower risk of preterm birth were commonly characterised by high consumption of vegetables, fruits, whole grains, fish and dairy products. Those associated with a lower risk of SGA also had similar characteristics, including high consumption of vegetables, fruits, legumes, seafood/fish and milk products. Results from a limited number of studies suggested there was a beneficial effect on the risk of preterm birth of pre-pregnancy diet quality characterised by a high intake of fruits and proteins and less intake of added sugars, saturated fats and fast foods. The evidence was mixed for the relationship between maternal dietary patterns during pregnancy and LBW. These findings indicate that better maternal diet quality during pregnancy, characterised by a high intake of vegetables, fruits, whole grains, dairy products and protein diets, may have a synergistic effect on reducing the risk of preterm birth and SGA.

Mid-arm muscle area and anthropometry predict low birth weight and poor pregnancy outcomes in Tanzanian women with HIV

BackgroundAn observational study was conducted to examine the role of maternal anthropometry, including mid-arm muscle area (MAMA) and others, as risk factors for low birth weight (LBW), small for gestational age (SGA) and preterm births in human immunodeficiency virus (HIV) infected pregnant women. HIV-positive women (N = 2369), between 12 and 32 weeks gestation were followed through delivery in Tanzania, from 2003 to 2008. Participants were women enrolled in a randomized, double-blind, placebo-controlled, clinical trial who delivered live births.MethodsBinomial regression analysis was used to evaluate the association of maternal nutritional indicators of MAMA, mid-upper arm circumference (MUAC), body mass index (BMI) and maternal weight with LBW, SGA and preterm in multivariate analysis.ResultsHigher MAMA was associated with a 32% lower risk of LBW compared to lower measurements (RR = 0.68, 95% CI = 0.50–0.94). Similar protective associations were noted for higher BMI (RR = 0.58, 95% CI = 0.42–0.79); maternal weight (RR = 0.50, 95% CI = 0.36–0.69) and MUAC (RR = 0.62, 95% CI = 0.45–0.86). Higher MAMA was also associated with lower risk of SGA (RR = 0.78, 95% CI = 0.68–0.90) and marginally associated with preterm (RR = 0.85, 95% CI = 0.69–1.04). Beneficial associations of MUAC, BMI and maternal weight with SGA and preterm were also observed.ConclusionMAMA performs comparably to MUAC, maternal weight and BMI, as a predictor of LBW and SGA in HIV-infected women. The possible role of MAMA and other indicators in screening HIV positive women at risk of adverse pregnancy outcomes should be investigated.

Maternal dietary consumption of legumes, vegetables and fruit during pregnancy, does it protect against small for gestational age?

BackgroundDifferent diets during pregnancy might have an impact on the health, reflected in the birthweight of newborns. The consumption of fruits and vegetables during pregnancy and the relationship with newborn health status have been studied by several authors. However, these studies have shown inconsistent results. Purpose: We assessed whether certain foods were related to the risk of small for gestational age (SGA).MethodsA matched by age (± 2 years) and hospital 1:1 case-control study of 518 pairs of pregnant Spanish women in five hospitals was conducted. The cases were women with an SGA newborn at delivery (neonates weighting less than the 10th percentile, adjusted for gestational age at delivery and sex, were diagnosed as SGA). The control group comprised women giving birth to babies adequate for gestational age (AGA). Mothers who gave birth to babies large for gestational age (LGA) were excluded. Data were gathered concerning demographic characteristics, socioeconomic status, toxic habits and diet. A food frequency questionnaire (FFQ) comprising 137 items was completed by all participants. The intake of vegetables, legumes and fruits was categorized in quintiles (Q1–Q5). Crude values and and adjusted odds ratios (AORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression. The variables for adjustment were as follows: preeclampsia, education, smoking, weight gain per week during pregnancy, fish intake and previous preterm/low birthweight newborns.ResultsTotal pulse intake showed an inverse association with the risk of SGA (trend p = 0.02). Women with an intake of fruits above 420 g/day (Q5), compared with women in Q1 (≤ 121 g/day) showed a decreased risk of SGA (AOR = 0.63, 95% CI = 0.40–0.98). The total consumption of vegetables was not associated with the risk of SGA. The intake of selenium was assessed: a protective association was observed for Q3–5; a daily intake above 60 μg was associated with a lower risk of SGA (AOR = 0.39, 95% CI: 0.22–0.69).ConclusionsFruits, pulses and selenium reduce the risk of SGA in Spanish women.