BACKGROUND: Nationwide evidence linking maternal ozone exposure with fetal growth restriction (FGR) was extensively scarce, especially in the Middle East with dry climate and distinct religious culture.
METHODS: We carried out a national retrospective birth cohort study using registry-based records from 749 hospitals across 31 provinces in Iran from 2013 to 2018. Monthly concentrations of maximum daily average 8-hour (MDA8) ozone at 0.125° × 0.125° resolution were extracted from well-validated spatiotemporal grid dataset. Linear and logistic regression models were employed to evaluate associations of maternal MDA8 ozone exposure with birthweight outcomes. Assuming causality, the comparative risk assessment framework was utilized to estimate the burden of low birthweight (LBW), small for gestational age (SGA), and birthweight loss per livebirth (BLL) attributable to ambient ozone pollution.
RESULTS: Of 4030383 livebirths included in the study, 264304 (6.6%) were LBW and 484405 (12.0%) were SGA. Each 10-ppb increase in MDA8 ozone exposure was associated with an odds ratio of 1.123 (95% confidence interval [CI]: 1.104 to 1.142) for LBW and 1.210 (95% CI: 1.197 to 1.223) for SGA, and a 30.5-g (95% CI: 29.0 to 32.0) reduction in birthweight. We observed approximately linear exposure-response relationships of maternal MDA8 ozone exposure with LBW (Pnonlinear= 0.786), SGA (Pnonlinear= 0.156), and birthweight reduction (Pnonlinear= 0.104). Under the premise of causal association, we estimated 6.6% (95% CI: 5.7 to 7.5) of LBW, 10.1% (95% CI: 9.6 to 10.6) of SGA, and 18.8 g (95% CI: 17.9 to 19.7) of BLL could be attributable to maternal ozone exposure in Iran. Considerably greater risk and burden of ozone-related FGR were observed among younger, less-educated, and rural-dwelling mothers.
CONCLUSIONS: Our study provided compelling evidence that maternal ozone exposure was associated with heightened FGR risk and burden, particularly among socioeconomically disadvantaged mothers. These findings underscored the urgent need for government to incorporate socioeconomic factors into future ozone-related health policies, not only to mitigate pollution, but also minimize inequality.

OBJECTIVE: This Mendelian randomisation (MR) study endeavoured to delineate the causal relationship between periodontitis and adverse pregnancy outcomes (APOs), encompassing low birthweight (LBW), pre-term birth (PTB), stillbirth, miscarriage, and gestational hypertension (GH).
METHODS: Utilising genetic instruments for periodontitis (acute and chronic periodontitis) from the Genome-Wide Association Study (GWAS) database among individuals of European descent, this study explored the causal relationship with adverse pregnancy outcomes, and vice versa. The Inverse Variance Weighted (IVW) method was employed as the primary analytical approach to assess causality, with MR-Egger serving as a sensitivity analysis method.
RESULTS: The primary analytical method employed in this study, IVW, did not reveal any impact of periodontitis (acute and chronic periodontitis) on PTB, stillbirth, miscarriage, and gestational hypertension, and vice versa. Heterogeneity testing using the MR-Egger method confirmed the null causal hypothesis, with odds ratios (OR) approximating 1, and P-values exceeding 0.05. Notably, the results from the IVW analysis (OR 1.410, CI 1.039-1.915, P-value 0.028) indicate statistically significant evidence supporting a causal relationship between chronic periodontitis and LBW. However, caution is advised in interpreting the causal relationship, considering the non-significant P-values obtained from other methods.
CONCLUSIONS: Within the limitations of this MR study, the findings do not support the influence of periodontitis on LBW, PTB, stillbirth, miscarriage, and GH, nor vice versa.

OBJECTIVE: To describe the mortality risks by fine strata of gestational age and birthweight among 230 679 live births in nine low- and middle-income countries (LMICs) from 2000 to 2017.
METHODS: Descriptive multi-country secondary data analysis.
METHODS: Nine LMICs in sub-Saharan Africa, Southern and Eastern Asia, and Latin America.
METHODS: Liveborn infants from 15 population-based cohorts.
METHODS: Subnational, population-based studies with high-quality birth outcome data were invited to join the Vulnerable Newborn Measurement Collaboration. All studies included birthweight, gestational age measured by ultrasound or last menstrual period, infant sex and neonatal survival. We defined adequate birthweight as 2500-3999 g (reference category), macrosomia as ≥4000 g, moderate low as 1500-2499 g and very low birthweight as <1500 g. We analysed fine strata classifications of preterm, term and post-term: ≥42+0 , 39+0 -41+6 (reference category), 37+0 -38+6 , 34+0 -36+6 ,34+0 -36+6 ,32+0 -33+6 , 30+0 -31+6 , 28+0 -29+6 and less than 28 weeks.
METHODS: Median and interquartile ranges by study for neonatal mortality rates (NMR) and relative risks (RR). We also performed meta-analysis for the relative mortality risks with 95% confidence intervals (CIs) by the fine categories, stratified by regional study setting (sub-Saharan Africa and Southern Asia) and study-level NMR (≤25 versus >25 neonatal deaths per 1000 live births).
RESULTS: We found a dose-response relationship between lower gestational ages and birthweights with increasing neonatal mortality risks. The highest NMR and RR were among preterm babies born at <28 weeks (median NMR 359.2 per 1000 live births; RR 18.0, 95% CI 8.6-37.6) and very low birthweight (462.8 per 1000 live births; RR 43.4, 95% CI 29.5-63.9). We found no statistically significant neonatal mortality risk for macrosomia (RR 1.1, 95% CI 0.6-3.0) but a statistically significant risk for all preterm babies, post-term babies (RR 1.3, 95% CI 1.1-1.5) and babies born at 370 -386  weeks (RR 1.2, 95% CI 1.0-1.4). There were no statistically significant differences by region or underlying neonatal mortality.
CONCLUSIONS: In addition to tracking vulnerable newborn types, monitoring finer categories of birthweight and gestational age will allow for better understanding of the predictors, interventions and health outcomes for vulnerable newborns. It is imperative that all newborns from live births and stillbirths have an accurate recorded weight and gestational age to track maternal and neonatal health and optimise prevention and care of vulnerable newborns.

Previous studies have shown conflicting findings regarding the association between birthweight and childhood adiposity. We aimed to explore the interaction between ultra-processed food (UPF) and birthweight and its associations with bodyweight markers. The retrospective analysis of data from a Multicity Cohort Study across eastern China was conducted. UPF was computed as percentage of the energy intake and categorized into quartiles. Birthweight was categorized into low (LBW), normal (NBW) and high (HBW). The BMI z-score was calculated using the lambda-mu-sigma method. The sex- and age-specific BMI cutoff points were used to define weight status. Generalized linear models were used to examine modification effects and were performed after adjustment for covariates. The mean percentage of energy intake from UPF was 27.7% among 1370 children. Of all children, 2.3% and 21.4% were born with LBW and HBW, respectively. HBW was a permanent risk for high BMI measures, while LBW was associated with increased BMI measurements only by the addition of the interaction term. The subgroup analysis revealed that HBW and LBW were positively associated with BMI measurements in the lowest UPF intake (Q1), while HBW was related to high BMI measures in Q4. Our findings support efforts to recommend limiting UPF intake, especially for LBW children.

With increasing cancer incidence and survival rates, the prevalence of maternal cancer and its effect on adverse birth outcomes are important for prenatal care and oncology management. However, the effects of different types of cancer at different gestational stages have not been widely reported.
This study aimed to describe the epidemiologic characteristics of pregnancy-associated cancers (during and 1 year after pregnancy) and evaluate the association between adverse birth outcomes and maternal cancers.
Of 983,162 cases, a history of maternal cancer, including pregestational cancer, pregnancy-associated cancer, and subsequent cancer, was identified in 16,475 cases using a health information network. The incidence and 95% confidence interval of pregnancy-associated cancer were calculated with the Poisson distribution. The adjusted risk ratio with 95% confidence interval of the association between adverse birth outcomes and maternal cancer were estimated using the multilevel log-binomial model.
A total of 38,295 offspring were born to mothers with a cancer history. Of these, 2583 (6.75%) were exposed to pregnancy-associated cancer, 30,706 (80.18%) had a subsequent cancer diagnosis, and 5006 (13.07%) were exposed to pregestational cancer. The incidence of pregnancy-associated cancer was 2.63 per 1000 pregnancies (95% confidence interval, 2.53‰-2.73‰), with cancer of the thyroid (1.15‰), breast (0.25‰), and female reproductive organs (0.23‰) being the most common cancer types. The increased risks of preterm birth and low birthweight were significantly associated with cancer diagnosed during the second and third trimester of pregnancy, whereas increased risks of birth defects (adjusted risk ratio, 1.48; 95% confidence interval, 1.08-2.04) were associated with cancer diagnosed in the first trimester. Increased risks of preterm birth (adjusted risk ratio, 1.16; 95% confidence interval, 1.02-1.32), low birthweight (adjusted risk ratio, 1.24; 95% confidence interval, 1.07-1.44), and birth defects (adjusted risk ratio, 1.22; 95% confidence interval, 1.10-1.35) were observed in thyroid cancer survivors.
Careful monitoring of fetal growth should be implemented for women diagnosed with cancer in the second and third trimester to ensure timely delivery and balance the benefits of neonatal health and cancer treatment. The higher incidence of thyroid cancer and increased risk of adverse birth outcomes among thyroid cancer survivors suggested that the regular thyroid function monitoring and regulation of thyroid hormone levels are important in maintaining pregnancy and promoting fetal development among thyroid cancer survivors before and during pregnancy.

OBJECTIVE: To examine prevalence of novel newborn types among 541 285 live births in 23 countries from 2000 to 2021.
METHODS: Descriptive multi-country secondary data analysis.
METHODS: Subnational, population-based birth cohort studies (n = 45) in 23 low- and middle-income countries (LMICs) spanning 2000-2021.
METHODS: Liveborn infants.
METHODS: Subnational, population-based studies with high-quality birth outcome data from LMICs were invited to join the Vulnerable Newborn Measurement Collaboration. We defined distinct newborn types using gestational age (preterm [PT], term [T]), birthweight for gestational age using INTERGROWTH-21st standards (small for gestational age [SGA], appropriate for gestational age [AGA] or large for gestational age [LGA]), and birthweight (low birthweight, LBW [<2500 g], nonLBW) as ten types (using all three outcomes), six types (by excluding the birthweight categorisation), and four types (by collapsing the AGA and LGA categories). We defined small types as those with at least one classification of LBW, PT or SGA. We presented study characteristics, participant characteristics, data missingness, and prevalence of newborn types by region and study.
RESULTS: Among 541 285 live births, 476 939 (88.1%) had non-missing and plausible values for gestational age, birthweight and sex required to construct the newborn types. The median prevalences of ten types across studies were T+AGA+nonLBW (58.0%), T+LGA+nonLBW (3.3%), T+AGA+LBW (0.5%), T+SGA+nonLBW (14.2%), T+SGA+LBW (7.1%), PT+LGA+nonLBW (1.6%), PT+LGA+LBW (0.2%), PT+AGA+nonLBW (3.7%), PT+AGA+LBW (3.6%) and PT+SGA+LBW (1.0%). The median prevalence of small types (six types, 37.6%) varied across studies and within regions and was higher in Southern Asia (52.4%) than in Sub-Saharan Africa (34.9%).
CONCLUSIONS: Further investigation is needed to describe the mortality risks associated with newborn types and understand the implications of this framework for local targeting of interventions to prevent adverse pregnancy outcomes in LMICs.

[This corrects the article DOI: 10.3389/fendo.2022.929617.].

Serum uric acid levels are elevated in polycystic ovary syndrome, however, the relationship between serum uric acid level and reproductive outcomes in women with polycystic ovary syndrome remains unclear.
This study aimed to investigate the association between serum uric acid level and the reproductive outcomes in women with polycystic ovary syndrome undergoing in vitro fertilization or intracytoplasmic sperm injection embryo transfer cycles.
This was a retrospective cohort study performed at a university-affiliated reproductive medicine center. A total of 1903 women with polycystic ovary syndrome undergoing their first in vitro fertilization or intracytoplasmic sperm injection embryo transfer cycles between January 2010 and January 2021 were initially included. The trends for reproductive outcomes in polycystic ovary syndrome across quartiles of serum uric acid levels were assessed. A logistic regression analysis was performed to obtain the odds ratios for in vitro fertilization outcomes based on the quartiles of serum uric acid with or without adjusting for potential confounding variables. Using generalized additive models, serum uric acid was further treated as its original continuous property to visualize its nonlinear relationship with in vitro fertilization outcomes. The live birth rate was the main outcome.
After exclusions, a total of 883 women with polycystic ovary syndrome with their first fresh-embryo transfer cycles were included. In quartiles of serum uric acid levels, there was a significant decreasing trend in the live birth rate from the lowest quartile (Q1: 61.8%) to the highest (Q4: 45.9%) (Ptrend=.002). The percentage of low birthweight increased from Q1 (22.3%) to Q4 (31.7%) (Ptrend=.049). Compared with those in Q1, women in Q4 showed a significant lower probability of live birth and clinical pregnancy and a higher risk for low birthweight (all P<.05). Both the unadjusted and adjusted generalized additive models indicated that as the serum uric acid level increased, the probability of clinical pregnancy and the live birth rate exhibited an overall decreasing profile, and the risk for low birthweight showed an increasing profile.
An elevated serum uric acid level is associated with decreased probabilities of live birth and clinical pregnancy and an increased risk for low birthweight in women with polycystic ovary syndrome. However, these associations may be confounded by other factors and more well-designed studies are needed to confirm these findings in the future.

UNASSIGNED: The application of peripherally inserted central venous catheters (PICCs) in neonates has proven effective in avoiding repetitive insertions and excessive use of transfusion consumables. However, the frequent occurrence of PICC-associated complications deserves special attention, especially in extremely or very low birthweight (E/VLBW) infants, which in turn affects the quality of neonatal PICC practice. Therefore, we conducted a retrospective study of a 3-year clinical practice of neonatal PICCs in E/VLBW infants to understand the incidences of various catheter-related complications and their risk factors to help form an empirical summary and evidence-based guidance for the improvement of practice.
UNASSIGNED: A retrospective study was conducted based on a 3-year practice of neonatal PICCs in E/VLBW infants. Neonatal health records were collected, including demographic characteristics, PICC placement data, and treatment information.
UNASSIGNED: A total of 519 E/VLBW infants were included in this study. There were 77 cases of complications involving 72 infants with an overall incidence of 12.13%. The order of incidences of different complications from high to low was phlebitis (7.71%), malposition (3.66%), leakage (1.35%), pleural effusion (1.15%), central line-associated bloodstream infection (0.58%, 0.25/1,000d), and accidental removal (0.38%). Multivariate analysis revealed that the inserted vessel was an independent risk factor for PICC-associated complications (mainly phlebitis; p = 0.002). Neonatal PICCs inserted in the axillary vein were only one-tenth (p = 0.026) as likely to cause phlebitis as in the basilic vein, whereas when applied in the saphenous vein, neonatal PICCs were five times as likely to cause phlebitis (p = 0.000).
UNASSIGNED: E/VLBW infants might be more inclined to develop PICC-associated phlebitis. Catheters inserted in the axillary or basilic vein are preferred if possible.

To explore the association between endometrial thickness (EMT) and adverse neonatal outcomes in frozen in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) cycles.
This retrospective study involved a total of 8,235 women under the age of 35 years who underwent IVF/ICSI cycles and received frozen embryo transfer (FET) at a tertiary-care academic medical from January 2015 to December 2019, resulting in a live singleton newborn. Patients were categorized into three groups depending on EMT: ≤7.5 mm, 7.5-12 mm and >12 mm. The primary outcome was low birthweight (LBW). The secondary outcomes were preterm birth (PTB), small-for-gestational age (SGA), large-for-gestational age (LGA) and high birthweight (HBW).
Compared with EMT >7.5-12 mm group, the risk of being born LBW was statistically significantly increased in the EMT ≤7.5 mm group (adjusted odds ratio [aOR] 2.179; 95% confidence interval [CI], 1.305-3.640; P=.003), while dramatically decreased in the EMT >12 mm group (aOR 0.584; 95% CI, 0.403-0.844; P=.004). Moreover, newborn gender and pregnancy complications were all independent predictors for LBW. Furthermore, a significant decrease in birthweight was found in the EMT ≤7.5 mm group as compared with EMT >7.5-12 mm group and EMT >12 mm group (3,239 ± 612 vs. 3,357 ± 512 and 3,374 ± 479 g, respectively), and similar result was found in term of gestational age (38.41 ± 2.19 vs. 39.01 ± 1.68 and 39.09 ± 1.5 weeks, respectively).
After frozen IVF/ICSI-ET, EMT ≤7.5 mm is independently associated with increased risk of LBW among women with singleton newborns. Therefore, we suggest that women with EMT ≤7.5 mm after achieving pregnancy by IVF/ICSI-ET treatment should warrant more attention to reduce the risk of delivering a LBW newborn.