Birth Weight Distribution Research Articles

A retrospective study: Risk factors and clinical presentation of neonatal surgical conditions

Background: Neonatal surgical conditions are a significant cause of morbidity and mortality in neonates. This study analyzed the socio-demographic characteristics, risk factors, types, and clinical presentation of surgical conditions of neonates admitted for surgical interventions. Objectives: To evaluate the clinical presentation of neonatal surgical conditions, assess maternal health and birth risk factors, and identify prevalent surgical diagnoses. Methods: This was a retrospective review of medical records of neonates admitted with surgical conditions at Khartoum Teaching Hospital and Ibrahim Malik Teaching Hospital from January 2020 to August 2022. Data collected included socio-demographic information, maternal health history, birth characteristics, symptom duration, and diagnosis. Results: 114 neonates' medical records were reviewed. The majority (66, 57.9%) presented within the first week of life, with a male-to-female ratio of 1.2:1. Most neonates (87, 76.3%) were born to non-consanguineous couples, and 108 (94.7%) had no family history of similar conditions. Maternal comorbidities were rare 2 (1.8%). Birth weight distribution showed that 94 (82.5%) were of average weight. Congenital surgical conditions constituted 113 (99.1%) of cases, most cases were gastrointestinal 59 (51.8%), followed by CNS cases 23 (20.2%), abdominal wall defects 12 (10.5%), urological defects 8 (7%), respiratory cases 1 (0.9%), and other miscellaneous cases 11 (9.6%). Anorectal malformations constituted the most common gastrointestinal condition, accounting for 16 cases (14%), followed by Hirschsprung disease 13 (11.4%), jejunal atresia 11 (9.6%), and malrotation 9 (7.8%). Conclusions: This study highlights the prevalence of congenital anomalies as the primary cause of neonatal surgical conditions, with gastrointestinal malformations being the most common. Early presentation within the first week of life and the absence of significant maternal or genetic risk factors were notable findings. Addressing the challenges of late diagnosis, inadequate prenatal screening, and resource limitations is essential for improving outcomes in neonatal surgical care.

Sex differences in delivery and neonatal characteristics of new-borns from the “MAMI-MED” cohort

IntroductionExploring modifiable and non-modifiable determinants—like sex of new-borns, maternal characteristics, and lifestyle—of maternal and child health is a priority in Public Health. Understanding these sex-based differences is essential for tailored care and informed public health policies.MethodsThe present study aimed to delineate sex disparities in delivery and neonatal characteristics within the “MAMI MED” cohort, an ongoing prospective study involving mother–child pairs from Catania, Italy. The analysis included 1,090 mother–child pairs.ResultsThe comparison of birth weight and birth length distribution showed some differences between sexes, confirmed by higher birth weight (β = 0.121; 95% CI = 0.071–0.172) and greater birth length (β = 0.659; 95% CI = 0.360–0.958) in males compared to females. However, the comparison of small and adequate for gestational age (SGA vs. AGA) revealed that the likelihood of being SGA was higher in males than in females (OR = 1.592; 95% CI = 1.005–2.563).DiscussionThus, the focus should be on improving the assessment of gender-based differences in diagnostic criteria and incorporating gender-specific aspects into existing preventive guidelines to deeply understand the effect of gender disparities and risk factors on maternal-child health.

ASSESSMENT OF UNIVERSAL NEONATAL HEARING SCREENING: OUTCOMES AND PREVALENCE AT A TERTIARY CARE CENTER

Objective: Early detection of hearing impairment through Universal Neonatal Hearing Screening (UNHS) is crucial for timely intervention. This study assesses the outcomes and prevalence of hearing loss in neonates screened at a tertiary care center. Methods: This prospective observational study involved 1175 neonates born at SDM Medical College and Hospital between December 2019 and November 2020. Neonates underwent initial and, if necessary, repeat hearing screenings using the Otoacoustic Emission (OAE) technique. Data on gender and birth weight distribution were also analyzed to explore demographic correlations with screening outcomes. Results: Of the neonates screened, 99.40% passed the initial hearing test, while 0.60% were referred for further evaluation. Among those referred, 71.43% passed on repeat screening, with 28.57% continuing to show potential hearing issues. The majority of neonates weighed over 2.5 kg, indicating a lower presence of very low birth weight infants in the screened population. Conclusion: The high pass rate in initial screenings demonstrates the effectiveness of the OAE method in a tertiary care setting, though the importance of follow-up testing for those referred remains critical. The study highlights the successful implementation of UNHS and underscores the need for continuous monitoring and adaptation of screening protocols to address all potential risks in neonatal hearing loss.

Glyphosate exposure and GM seed rollout unequally reduced perinatal health

The advent of herbicide-tolerant genetically modified (GM) crops spurred rapid and widespread use of the herbicide glyphosate throughout US agriculture. In the two decades following GM-seeds' introduction, the volume of glyphosate applied in the United States increased by more than 750%. Despite this breadth and scale, science and policy remain unresolved regarding the effects of glyphosate on human health. We identify the causal effect of glyphosate exposure on perinatal health by combining 1) county-level variation in glyphosate use driven by 2) the timing of the GM technology and 3) differential geographic suitability for GM crops. Our results suggest the introduction of GM seeds and glyphosate significantly reduced average birthweight and gestational length. While we find effects throughout the birthweight distribution, low expected-weight births experienced the largest reductions: Glyphosate's birthweight effect for births in the lowest decile is 12 times larger than that in the highest decile. Together, these estimates suggest that glyphosate exposure caused previously undocumented and unequal health costs for rural US communities over the last 20 years.

Study of Factors Influencing the Intestinal Microbiota in Children from 0 to 3 Months at the Mother and Child Hospital of Bingerville, Ivory Coast during 2023

Introduction: Every human being builds a symbiosis with a diverse ecosystem of microorganisms: the intestinal microbiota. Its establishment, maturity, and composition evolving throughout life are dynamic processes influenced during their establishment by various factors such as gestational age, birth and feeding modalities, environment, and antibiotic use. The aim of this article is to identify the epidemiological characteristics (factors influencing the establishment and development of the intestinal microbiota) of populations of children from 0 to 3 months studied at the Mother and Child Hospital of Bingerville. Methods: A longitudinal and prospective birth cohort of populations of children from Day 0 to Month 3 was conducted. Epidemiological data were collected from the mother after signing the informed consent form. Data collection tools included the survey form, information sheet, and informed consent form. Statistical analyses were performed using XLSTAT software version 2018. Chi-square test (significance test) was used on variables such as sex and gestational age, mode of delivery, gestational age and birth mode, and birth weight. Results: A total of 52 infants were included. The socio-demographic and clinical characteristics of these newborns and their mothers were examined. Analysis of birth weight distribution according to mode of delivery and feeding mode did not reveal any significant association. Each studied characteristic was then discussed. Conclusion: The objective of the study has been achieved. However, further research is needed to obtain more generalizable results.

A prospective study on the causes of hyperbilirubinemia and its clinical markers in term and near-term newborns admitted to a tertiary care hospital in Patna, India

This study aimed to investigate the root causes, prognostic factors, and therapeutic strategies for neonatal hyperbilirubinemia among term and near-term infants admitted to the Neonatal Intensive Care Unit (NICU) at IGIMS, Patna. Furthermore, the research aimed to analyze the clinical progression of these infants throughout their NICU stay.Conducted within the NICU at IGIMS, Patna, Bihar, this study encompassed term and late preterm infants admitted with serum bilirubin levels exceeding 12 mg/dl. The primary focus was on identifying risk factors, etiological factors, and the clinical profile of these infants during their NICU tenure.The study examined birth weight distribution and concurrent medical conditions. Parameters included the initiation of phototherapy based on bilirubin levels and treatment methodologies. Out of the 210 infants studied, 27.14% and 47.62% weighed between 2001 and 2500 grams. The most prevalent causes were physiological (129 cases), fetal prematurity (30 cases), birth asphyxia (7 cases), and prolonged labor (18 cases). Idiopathic causes were observed in 28 instances, ABO incompatibility in 7 cases, and Rh incompatibility in 7 cases. G6PD deficiency was identified once. At the commencement of phototherapy, 19.52% had bilirubin levels between 12 and 15 mg/dl, 58.57% between 15.1 and 18 mg/dl, 11.91% above 20 mg/dl, and 10% between 18.1 and 20 mg/dl.Physiological causes emerged as the most frequent contributors to neonatal hyperbilirubinemia, followed by septicemia and idiopathic factors. Infrequent causes included blood group incompatibility. Phototherapy was established as a cost-effective and efficient method for reducing bilirubin levels in neonatal jaundice. Exchange transfusion proved to be a safe therapeutic measure in cases of severe hyperbilirubinemia. Blood group incompatibility was the main determinant requiring exchange transfusion.

Assessment of Initial Morbidity Patterns in Late Preterm Infants Relative to Those at Term

The purpose of this research was to assess the patterns of morbidity and mortality in late preterm neonates—that is, neonates born before 37 weeks of gestation. Preterm births are a major contributing factor to many deaths in children under five, with a larger percentage of deaths occurring during the neonatal era. The study was a prospective observational cohort study carried out at DDU Hospital in New Delhi in the neonatal intensive care unit of the pediatrics department. While term neonates had a mean gestation distribution of 38.64 weeks, late preterm newborns had a mean distribution of 35.39 weeks. The distribution of mean birth weight was 2.35 (±0.48) and 3.04 (±0.43) kg. Males were seen often in both research groups. The distribution of hypoglycemia among the study groups showed a significant difference, with late preterm infants having a higher incidence of the condition. The rate of post-resuscitation care varied significantly as well, with late preterm infants needing greater attention. A statistically significant increase was observed in the incidence of respiratory distress in late preterm newborns. Compared to the other group, late preterm infants had a higher prevalence of jaundice and sepsis. The study finds that compared to term newborns, late preterm infants had a higher risk of morbidity. To have a better understanding of these children's neonatal outcomes, more research is required.

Selecting a birth weight standard for an indigenous population in a LMIC: A prospective comparative study.

The aim of the present study was to compare birth weight (BW) distribution and proportion of BWs below or above specified percentiles in low-risk singleton pregnancies in healthy South African (SA) women of mixed ancestry with expected values according to four BW references and to determine the physiological factors affecting BW. This was an ancillary study of a prospective multinational cohort study, involving 7060 women recruited between August 2007 and January 2015 in two townships of Cape Town, characterized by low socioeconomic status, and high levels of drinking and smoking. Detailed information about maternal and pregnancy characteristics, including harmful exposures, was gathered prospectively, allowing us to select healthy women with uncomplicated pregnancies without any known harmful exposures. In this cohort we compared the median BW and the proportion of BWs <P3, 5 and 10 or >P90, 95 and 97 according to four reference standards (INTERGROWTH-21st, customized according to the method described by Mickolajczyk, Fetal Medicine Foundation and revised Fenton reference) with expected values. Appropriate parametric and nonparametric tests were used, and sensitivity analysis was performed for infant sex, first trimester bookings and women of normal body mass index (BMI). Multiple regression was used to explore effects of confounders. Written consent and ethics approval was obtained. The cohort included 739 infants. The INTERGROWTH-21st standard was closest for the actual BW-distribution and categories. Below-expected BW was associated with boys, younger, shorter, leaner women, lower parity and gravidity. Actual BW was significantly influenced by maternal weight, BMI, parity and gestational age. Of the four references assessed in this study, the INTERGROWTH-21st standard was closest for the actual BW distribution. Maternal variables significantly influence BW.

Birth weight in the Northwest region of Argentina. Comparison with a national reference and an international standard.

Introduction. Size at birth is subject to genetic and environmental influences; altitude is highly influential. Birth weight (BW) is the most widely used indicator to assess size at birth; different standards and references are available. Due to the variability in BW distribution in relation to altitude in the province of Jujuy (Argentina), the purpose of this study is to analyze the percentile distribution of BW in the highlands (HL) and the lowlands (LL) of Jujuy based on gestational age (GA) and sex and compare it with a national reference and the INTERGROWTH-21st (IG-21) international standard. Population and methods. The records of 78 524 live births in Jujuy in the 2009-2014 period were analyzed. Using the LMS method, the 3rd, 10th, 50th, 90th, and 97th percentiles of BW/GA by sex were estimated for the HL (≥ 2000 MASL), the LL (< 2000 MASL), and the total for Jujuy, and compared with the Argentine population reference by Urquía and the IG-21 standard using growth charts. The statistical significance was established using the Wilcoxon test. Results. BW in Jujuy showed a heterogeneous distribution, with statistically significant differences (p < 0.05) between the LL and the HL. When compared with the national reference and the IG-21 standard, differences in terms of altitude were observed, mainly in the 90th and 97th percentiles for both regions and the 3rd and 10th percentiles in the HL compared with the international standard. Conclusions. BW distribution varied in association with altitude; therefore, to assess intrauterine growth, it is critical to include GA and the environment in which the pregnancy takes place.

Maternal Dengue and Health Outcomes of Children

We study the effect of maternal dengue infections on birth outcomes using linked administrative records from Brazil estimating maternal fixed-effect specifications. In contrast to previous studies, we find robust evidence for the negative effect of dengue infections on birth weight (BW). The effect is particularly pronounced at lower parts of the BW distribution, with an increase of 15 percent, 67 percent, and 133 percent for low, very low, and extremely low BW, respectively. We also document large increases in children’s hospitalizations and medical expenditures for up to three years after birth. (JEL I12, I18, J13, J16, O15)

Impact of Gestational Diabetes and Pre-existing Diabetes in Fetal Outcome among Pregnancy Cases of Rangpur

Introduction: Diabetes in pregnancy, including gestational and pre-gestational diabetes, presents significant risks to both maternal and fetal health. Understanding the impact of these conditions on pregnancy outcomes is crucial for developing effective management strategies.&#x0D; Methods: This observational comparative study involved 300 pregnant women at Rangpur Medical College Hospital, divided into three groups: pre-gestational diabetic (Group A), gestational diabetic (Group B), and non-diabetic control (Group C). Data on socio-demographic characteristics, obstetric profiles, mode of delivery, maternal complications, and fetal outcomes were collected and analyzed.&#x0D; Result: The study meticulously analyzed socio-demographic characteristics, revealing no significant differences across the groups. In obstetric profiles, Group A (Pre-Gestational Diabetic) had a notably lower mean gestational age at delivery (36.06 ± 2.71 weeks) compared to Group B (Gestational Diabetic) and Group C (Control), with mean ages of 37.34± 1.12 and 38.46±1.13 weeks, respectively. Maternal complications were significantly higher in Group A at 47%, compared to 25% in Group B and 12% in Group C. Fetal outcomes showed marked variations: Group A had 95% stable births, 5% stillbirths, and 60% of neonates with Apgar scores ≤7 at 5 minutes. In contrast, Group B had 96% stable births, 4% stillbirths, and 27% of neonates with Apgar scores ≤7, while Group C reported 100% stable births and 11% with Apgar scores ≤7. Birth weight distribution indicated 24% of neonates in Group A weighed &lt;2 kg, compared to 5% in Group B and 4% in Group C. NICU admissions were highest in Group A (44%), followed by Group B (29%) and Group C (11%). Perinatal complications like birth asphyxia (38% in Group A, 16% in Group B, 6% in Group C), hypoglycemia (22% in Group A, 10% in Group B, 4% in Group C), and hyperbilirubinemia (16% in Group A, 12% in Group B, 0% in Group C) were also significantly higher in diabetic groups.&#x0D; Conclusion: The presence of gestational or pre-gestational diabetes in mothers significantly impacts fetal outcomes and increases the risk of maternal complications. This study highlights the need for specialized care and vigilant monitoring in pregnancies complicated by diabetes to improve health outcomes for mothers and babies.&#x0D;

Characteristics of stunting in children in the Kintamani III Community Health Center area, Bangli District

Background: Stunting is a chronic physical growth disorder in children characterized by a decrease in growth rate and is influenced by nutritional imbalances over a long period with a WHO MGRS z-score value of less than -2 SD. This condition has a fairly high incidence rate in Indonesia, especially in Bangli, Bali, which is caused by various factors. This research was conducted to determine the characteristics of stunting in children in the Kintamani III Community Health Center area, Bangli district. Methods: We conducted a descriptive cross-sectional study from February to December 2022. The parameters assessed in this study are family income, maternal education, additional food, birth weight, history of infection, exclusive breastfeeding, high genetic potential, environmental sanitation, mother age, gender, and birth spacing. Data were analyzed with SPSS version 25.0 for Windows. Results: There were 70 children with stunting were involved in this research. The research subjects were mostly female (55.7%), the highest birth weight distribution was in the range of 2500-4000 grams (90%), there was no history of infection (88.6%), exclusive breastfeeding was given for 6 months or more ( 92.9%), birth interval more than or equal to 2 years (77.1%), additional food given 3 times a day (80%) which is higher in stunting population compare to severely stunting, average genetic potential height 159.36 + 8.03, mother's age 20-35 years (81.4%), maternal high school education (32.4%), family income above minimum wage (UMK) (87.1%). Conclusion: This research shows that patients with severe stunting tend to have a lower frequency of additional food.

Intravenous Iron Therapy in Severe Anemia at 28-34 Weeks of Gestation and it’s Feto-Maternal Outcome- A Prospective Study from A Developing Country

Introduction: Iron deficiency anaemia (IDA) is the most common nutritional deficiency in pregnancy. Anemia results in poor pregnancy outcome and also affects fetal outcome. This study was undertaken to evaluate the response of intravenous iron given to pregnant women with severe IDA and their feto-maternal outcome.&#x0D; Methodology: A prospective study was conducted in the department of Obstetrics &amp; Gynaecology, at a tertiary care centre of Northern India. Fifty-two pregnant women with haemoglobin between 5-7 g% with diagnosed iron deficiency attending antenatal clinic were given intravenous iron complex Follow-up after 4 weeks was done and IDA specific blood profile was done at baseline and at follow-up. Feto-maternal outcomes were seen at delivery.&#x0D; Results: The mean age of study population was 25.5 ± 3.96 yrs. Improvement at 4 week follow-up from baseline in hemoglobin (p value-0.001) and iron profiles (S. Iron, Total Iron Binding Capacity (TIBC), S. Ferritin) (p value -0.0001) were highly significant. On comparing the Hb levels at delivery after intravenous infusion at 28-34 weeks gestation, 17 patients were still below 8 gm%, whereas 35 were above 8 gm%. Distribution of IUGR, preterm labor and blood transfusion in postpartum period were statistically significant amongst both group (p value&lt;0.05). Fetal outcomes were also evaluated amongst the 2 groups. Distribution of Preterm birth, birth weight and NICU admission was also statistically significant (p value&lt;0.05).&#x0D; Conclusion: The intravascular iron therapy definitely has a rapid increase in haemoglobin which can prevent the complications due to severe anaemia in pregnancy and blood transfusion can also be prevented, but iron stores are not replenished to the optimum level, so there is a need to give replacement therapy (by oral route) post transfusion for long term benefits. The rise of hemoglobin affects feto-maternal outcomes even in the last trimester.contrast agents. This is a first case report of AHCM portrayed by this ingenious technology.&#x0D; Keywords: AMCH, IUGR, TIBC

Bivariate Analysis of Birth Weight and Gestational Age by Bayesian Distributional Regression with Copulas

We analyze perinatal data including biometric and obstetric information as well as data on maternal smoking, among others. Birth weight is the primarily interesting response variable. Gestational age is usually an important covariate and included in polynomial form. However, in opposition to this univariate regression, bivariate modeling of birth weight and gestational age is recommended to distinguish effects on each, on both, and between them. Rather than a parametric bivariate distribution, we apply conditional copula regression, where the marginal distributions of birth weight and gestational age (not necessarily of the same form) and the dependence structure are modeled conditionally on covariates. In the resulting distributional regression model, all parameters of the two marginals and the copula parameter are observation specific. While the Gaussian distribution is suitable for birth weight, the skewed gestational age data are better modeled by the three-parameter Dagum distribution. The Clayton copula performs better than the Gumbel and the symmetric Gaussian copula, indicating lower tail dependence (stronger dependence when both variables are low), although this non-linear dependence between birth weight and gestational age is surprisingly weak and only influenced by Cesarean section. A non-linear trend of birth weight on gestational age is detected by a univariate model that is polynomial with respect to the effect of gestational age. Covariate effects on the expected birth weight are similar in our copula regression model and a univariate regression model, while distributional copula regression reveals further insights, such as effects of covariates on the association between birth weight and gestational age.

The Impact of COVID-19 on Birth Weight during Pregnancy

Introduction: Coronavirus is a viral pathogen that can be transmitted through respiratory droplets, leading to severe infectious diseases. This study aimed to ascertain the influence of the COVID-19 pandemic on birth weight during pregnancy. Methods: This study used secondary data and a retrospective case-control approach for observational analysis. The case and control groups each had 153 samples. The case group was further separated into symptomatic and asymptomatic categories. Statistical analyses were performed to determine how COVID-19 infection in pregnant women affected birth weight. Fisher’s exact test was used to evaluate data for the subgroups of asymptomatic and symptomatic individuals, while the Mann-Whitney test was used to compare the infection's impact. Results: Most participants were 21–35 years old (78.2%). The findings showed that 85% of pregnant COVID-19 patients were in their third trimester. Mothers diagnosed with COVID-19 had infants with birth weights of &gt;4,000 grams (3.3%), 2,500–4,000 grams (43.1%), and &lt;2,500 grams (53.6%). Birth weight distribution in women unaffected by COVID-19 was &gt;4,000 grams (14.4%), 2,500–4,000 grams (67.3%), and &lt;2,500 grams (18.3%). The Mann-Whitney statistical test was performed using SPSS. It yielded a p-value of 0.001, less than the significance level of 0.05, indicating a correlation between confirmed COVID-19 infection in pregnant women and birth weight. Conclusion: This study found that the presence of COVID-19 infection during pregnancy significantly affects infants' birth weight.

Impact of Gestational and Pre-Gestational Diabetes on Maternal Complications and Fetal Outcomes: A Comparative Observational Study at Rangpur Medical College Hospital

Introduction: Diabetes in pregnancy, including gestational and pre-gestational diabetes, presents significant risks to both maternal and fetal health. Understanding the impact of these conditions on pregnancy outcomes is crucial for developing effective management strategies.Methods: This observational comparative study involved 300 pregnant women at Rangpur Medical College Hospital, divided into three groups: pre-gestational diabetic (Group A), gestational diabetic (Group B), and non-diabetic control (Group C). Data on socio-demographic characteristics, obstetric profiles, mode of delivery, maternal complications, and fetal outcomes were collected and analyzed.Result: The study meticulously analyzed socio-demographic characteristics, revealing no significant differences across the groups. In obstetric profiles, Group A (Pre-Gestational Diabetic) had a notably lower mean gestational age at delivery (36.06 ± 2.71 weeks) compared to Group B (Gestational Diabetic) and Group C (Control), with mean ages of 37.34± 1.12 and 38.46±1.13 weeks, respectively. Maternal complications were significantly higher in Group A at 47%, compared to 25% in Group B and 12% in Group C. Fetal outcomes showed marked variations: Group A had 95% stable births, 5% stillbirths, and 60% of neonates with Apgar scores ≤7 at 5 minutes. In contrast, Group B had 96% stable births, 4% stillbirths, and 27% of neonates with Apgar scores ≤7, while Group C reported 100% stable births and 11% with Apgar scores ≤7. Birth weight distribution indicated 24% of neonates in Group A weighed &lt;2 kg, compared to 5% in Group B and 4% in Group C. NICU admissions were highest in Group A (44%), followed by Group B (29%) and Group C (11%). Perinatal complications like birth asphyxia (38% in Group A, 16% in Group B, 6% in Group C), hypoglycemia (22% in Group A, 10% in Group B, 4% in Group C), and hyperbilirubinemia (16% in Group A, 12% in Group B, 0% in Group C) were also significantly higher in diabetic groups.Conclusion: The presence of gestational or pre-gestational diabetes in mothers significantly impacts fetal outcomes and increases the risk of maternal complications. This study highlights the need for specialized care and vigilant monitoring in pregnancies complicated by diabetes to improve health outcomes for mothers and babies.

Projecting future prolapse outcomes with induction of labor at 39 weeks: a decision analysis.

In 2018, the ARRIVE trial (A Randomized Trial of Induction Versus Expectant Management) concluded that routine induction of labor (IOL) at 39 weeks gestation decreases cesarean delivery risk, with slightly lighter birthweight infants. We debated whether routine IOL would improve, worsen, or not change POP risk compared with expectant management (EM). We constructed a decision analysis model with a lifetime horizon where nulliparous women reaching 39 weeks underwent IOL or EM. Subsequent vaginal versus cesarean delivery varied based on prior deliveries for up to four births. Subsequent delivery prior to 39 weeks and distribution of gestational age, birthweight, and delivery mode between 24 and 39 weeks was modeled from national data. We modeled increased POP risk with increasing vaginal parity, forceps delivery, and weight of largest infant delivered vaginally, accounting for differential infant weights in each strategy. IOL and EM have similar population-wide POP risk (15.9% and 15.7% respectively). Among women with only spontaneous vaginal deliveries that reached 39 weeks or beyond, the prevalence of POP was 20% after one delivery and 29% after four deliveries, with no difference between groups. The cesarean rate was lower with IOL (27.8% versus 29.8%). Sensitivity analysis revealed no meaningful thresholds among the variables, supporting model robustness. While routine induction of labor at 39 weeks results in a meaningfully higher vaginal delivery rate, there was no increase in POP, possibly due to the protective effect of lower birthweight.

Birthweight of the subsequent singleton pregnancy following a first twin or singleton pregnancy.

Birthweight is an important pregnancy indicator strongly associated with infant, child, and later adult life health. Previous studies have found that second-born babies are, on average, heavier than first-born babies, indicating an independent effect of parity on birthweight. Existing data are mostly based on singleton pregnancies and do not consider higher order pregnancies. We aimed to compare birthweight in singleton pregnancies following a first twin pregnancy relative to a first singleton pregnancy. This was a prospective registry-based cohort study using maternally linked offspring with first and subsequent pregnancies registered in the Medical Birth Registry of Norway between 1967 and 2020. We studied offspring birthweights of 778 975 women, of which 4849 had twins and 774 126 had singletons in their first pregnancy. Associations between twin or singleton status of the first pregnancy and birthweight (grams) in subsequent singleton pregnancies were evaluated by linear regression adjusted for maternal age at first delivery, year of first pregnancy, maternal education, and country of birth. We used plots to visualize the distribution of birthweight in the first and subsequent pregnancies. Mean combined birthweight of first-born twins was more than 1000 g larger than mean birthweight of first-born singletons. When comparing mean birthweight of a subsequent singleton baby following first-born twins with those following first-born singletons, the adjusted difference was just 21 g (95% confidence interval 5-37 g). Birthweights of the subsequent singleton baby were similar for women with a first twin or a first singleton pregnancy. Although first twin pregnancies contribute a greater combined total offspring birthweight including more extensive uterine expansion, this does not explain the general parity effect seen in birthweight. The physiological reasons for increased birthweight with parity remain to be established.

Birth size, school performance and family social position: a study of 650,000 children

BackgroundLow birth weight (BW) is associated with lower cognitive functioning, but less is known of these associations across the full range of the BW distribution and its components. We analyzed how BW, birth length (BL) and birth ponderal index (BPI, kg/m3) are associated with school performance and how childhood family social position modifies these associations.MethodsMedical birth records of all Finnish children born in 1987–1997 were linked to school performance records at 16 years of age (N = 642,425). We used population averaged and within-siblings fixed-effects linear regression models.ResultsBL showed a linear and BW a curvilinear association with school performance whereas for BPI the association was weak. The strongest association was found for BL explaining 0.08% of the variation in school performance in boys and 0.14% in girls. Demographic, gestational and social factors partly explained these associations. Similar but weaker associations were found within sibships. The association of BL with school performance was stronger at lower levels of family social position.ConclusionBL shows a linear association with school performance and can explain more school performance variation than BW. At the population level, BL can offer useful information on intrauterine environmental factors relevant for cognitive performance.ImpactBirth length is linearly associated with school performance in late adolescence and explains a larger proportion of school performance variation than birth weight.The association between birth length and school performance is stronger in families with lower socio-economic position.At the population level, birth length can offer information on the intrauterine environment relevant for later cognitive performance.

Review: Targeted nutrition in gestating sows: opportunities to enhance sow performance and piglet vitality.

Birth weight is a key factor for piglet survival, and therefore, there is ongoing interest in how nutrition during gestation can influence birth weight. Interestingly, sows are generally fed one single diet throughout gestation. This paper reviews past attempts to increase foetal growth to term and discusses opportunities to target nutritional manipulations at specific windows of gestation where key developmental events occur. Birth weight limits chances to survive mainly in piglets with birth weight below 1kg. These piglets represent around 16% of the population. Given the normal distribution of birth weight, the mean birth weight needs to be increased by at least 50-100g to have a meaningful impact on this proportion of the population and on perinatal survival. Based on existing variation in reported mean birth weight across a number of studies, it is argued that it is unrealistic to expect an increase in mean birth weight of more than 100g. Attempts in the past to increase birth weight have focussed on the last trimester of gestation, when foetal growth is accelerated. Increase in feed allowance or nutritional concepts that target placenta vascularisation have not been successful. It is argued that nutritional manipulations should rather focus on the middle of gestation, since in that period, placenta growth occurs and since placenta size limits the foetal size. Alternatively, nutritional manipulations can target placentation during the embryonic phase.