New birthweight charts according to parity and type of delivery for the Spanish population

Midwife-attended planned home births versus planned hospital births in Spain: Maternal and neonatal outcomes

BACKGROUND

The debate on the safety and outcomes of home versus hospital births highlights the need for evidence-based evaluations of these birthing settings, particularly in Catalonia where both options are available.

AIM

To compare sociodemographic characteristics and maternal and neonatal outcomes between low-risk women opting for home versus hospital births in Catalonia, Spain.

METHODS

This observational cross-sectional study analysed 3,463 low-risk births between 2016 and 2018, including 2,713 hospital and 750 home births. Researchers collected sociodemographic data, birthing processes, and outcomes, using statistical analysis to explore differences between the settings.

FINDINGS

Notable differences emerged: Women choosing home births typically had higher education levels and were predominantly Spanish. They were 3.43 times more likely to have a spontaneous birth and significantly less likely to undergo instrumental births than those in hospitals. Home births were associated with higher utilization of non-pharmacological analgesia and a more pronounced tendency to iniciate breastfeeding within the first hour post birth and stronger inclination towards breastfeeding. Hospital births, conversely, showed higher use of the lithotomy position and epidural analgesia. There were no significant differences in neonatal outcomes between the two groups.

CONCLUSIONS AND IMPLICATION FOR PRACTICE

Home births managed by midwives offered better obstetric and neonatal outcomes for low-risk women than hospital births. These results suggest home birth as a safe, viable option that promotes natural birthing processes and reduces medical interventions. The study supports the integration of midwife-led home birth into public health policies, affirming its benefits for maternal and neonatal health.

The smaller firstborn: exploring the association of parity and fetal growth

PURPOSE

To investigate the association of parity with a range of neonatal anthropometric measurements in a cohort of uncomplicated term singleton pregnancies.

METHODS

Retrospective cohort study of patients with a singleton term birth at a single tertiary center (2014-2020) was carried out. The primary exposure was parity. The following neonatal anthropometric measures were considered: birthweight, head circumference, length, ponderal index, and neonatal body mass index (BMI).

RESULTS

A total of 8134 patients met the study criteria, 1949 (24.0%) of whom were nulliparous. Compared with multiparous patients, infants of nulliparous patients had a lower mean percentile for birthweight (43.1 ± 26.4 vs. 48.3 ± 26.8 percentile, p < 0.001), head circumference (44.3 ± 26.4 vs. 48.1 ± 25.5 percentile, p < 0.001), length (52.6 ± 25.1 vs. 55.5 ± 24.6 percentile, p < 0.001), ponderal index (34.4 ± 24.0 vs. 37.6 ± 24.2 percentile, p < 0.001), and BMI (39.1 ± 27.1 vs. 43.9 ± 27.3 percentile, p < 0.001). In addition, infants of nulliparous patients had higher odds of having a small (< 10th percentile for gestational age) birthweight (aOR 1.32 [95% CI 1.12-1.56]), head circumference (aOR 1.54 [95% CI 1.29-1.84]), length (aOR 1.50 [95% CI 1.16-1.94]), ponderal index (aOR 1.30 [95% CI 1.12-1.51]), and body mass index (aOR 1.42 [95% CI 1.22-1.65]). Most neonatal anthropometric measures increased with parity until a parity of 2, where it seemed to reach a plateau.

CONCLUSION

Parity has an independent impact on a wide range of neonatal anthropometric measures, suggesting that parity is associated with both fetal skeletal growth and body composition. In addition, the association of parity with fetal growth does not follow a continuous relationship but instead reaches a plateau after the second pregnancy.

Birthweight trends and their explanatory factors in Hungary between 1999 and 2018: an analysis of the Hungarian Tauffer registry

BACKGROUND

The increasing birthweight trend stopped and even reversed in several high income countries in the last 20 years, however the reason for these changes is not well characterized. We aimed to describe birthweight trends of term deliveries in Hungary between 1999 and 2018 and to investigate potential maternal and foetal variables that could drive these changes.

METHODS

We analysed data from the Hungarian Tauffer registry, a compulsory anonymized data collection of each delivery. We included all singleton term deliveries in 1999-2018 (n = 1,591,932). We modelled birthweight trends separately in 1999-2008 and 2008-2018 in hierarchical multiple linear regression models adjusted for calendar year, newborn sex, maternal age, gestational age at delivery, and other important determinants.

RESULTS

Median birthweights increased from 3250/3400 g (girl/boy) to 3300/3440 g from 1999 to 2008 and decreased to 3260/3400 g in 2018. When we adjusted for gestational age at delivery the increase in the first period became more pronounced (5.4 g/year). During the second period, similar adjustment substantially decreased the rate of decline from 2.5 to 1.4 g/year. Further adjustment for maternal age halved the rate of increase to 2.4 g/year in the first period. During the second period, adjustment for maternal age had little effect on the estimate.

CONCLUSIONS

Our findings of an increasing birthweight trend (mostly related to the aging of the mothers) in 1999-2008 may forecast an increased risk of cardiometabolic diseases in offsprings born in this period. In contrast, the decreasing birthweight trends after 2008 may reflect some beneficial effects on perinatal morbidity. However, the long-term effect cannot be predicted, as the trend is mostly explained by the shorter pregnancies.

Perinatal outcomes in 6640 singleton pregnancies after donor oocyte IVF across three continents over 7 years

PURPOSE

Are trends in singleton donor oocyte IVF perinatal outcomes consistent over time among four international ethnically diverse infertility centers?

METHODS

This retrospective cohort consisted of an infertility network of four international IVF centers across three continents. Singleton live births resulting from fresh and frozen donor oocyte embryo transfers from January 1, 2012 to December 31, 2018 were included. The main outcome measures were birth weight (BW), preterm birth (PTB), large for gestational age (LGA), small for gestational age (SGA) and gestational age (GA) at delivery.

RESULTS

The entire cohort (n = 6640) consisted of 4753 fresh and 1887 frozen donor oocyte embryo transfers. Maternal age, parity, body mass index, neonatal sex and GA at delivery were similar for fresh and frozen donor oocyte embryo transfers in the entire cohort and within each infertility center. All four centers had a trend of decreased BW and rates of PTB before 32 weeks annually, although significance was not reached. Three of the four centers had annual increased trends of PTB before 37 weeks and LGA newborns, although significance was not reached. BWs for the entire cohort for fresh and frozen donor embryo transfers were 3166 g ± 601 g and 3137 g ± 626 g, respectively.

CONCLUSION

Similar trends in perinatal outcomes were present across four international infertility centers over 7 years. The overall perinatal trends in donor oocyte IVF may be applicable to centers worldwide, but further studies in more geographic regions are needed.

Perinatal outcomes in 13,626 singleton pregnancies after autologous IVF across three continents over 7 years

PURPOSE

Are trends in singleton autologous IVF perinatal outcomes consistent over time among five international infertility centers?

METHODS

This was a retrospective cohort study from January 1, 2012, to December 31, 2018. This study was performed through a large infertility network at five international infertility centers in which patients who had a singleton live birth resulting from fresh and frozen autologous IVF cycles were included. The primary outcome was live birth weight (BW) with secondary outcomes of preterm birth (PTB), large for gestational age (LGA), small for gestational age (SGA), and gestational age at delivery.

RESULTS

The entire cohort (n = 13,626) consisted of 6941 fresh and 6685 frozen autologous IVF cycles leading to singleton deliveries. Maternal age, parity, body mass index, neonatal sex, and GA at delivery were similar for fresh and frozen IVF cycles in the entire cohort and within each infertility center. Four centers had a trend of decreased BW and three centers had decreased rates of PTB before 32 and 28 weeks and LGA newborns annually, although significance was not reached. Three IVF centers had annual increased trends of PTB before 37 weeks and four centers had increased rates of SGA newborns, although significance was not reached.

CONCLUSION

Similar trends in perinatal outcomes were present across five international infertility centers over 7 years. Additional studies are crucial to further assess and optimize perinatal outcomes at an international level.

Prenatal Betamethasone Exposure and its Impact on Pediatric Type 1 Diabetes Mellitus: A Preliminary Study in a Spanish Cohort

BACKGROUND

Betamethasone, a glucocorticoid used to induce lung maturation when there is a risk of preterm delivery, can affect the immune system maturation and type 1 diabetes (T1D) incidence in the progeny. It has been described that prenatal betamethasone protects offspring from experimental T1D development. The main aim of this study was to evaluate the possible association between betamethasone prenatal exposure and T1D in humans. Research Design and Methods. A retrospective case-control study with a total of 945 children, including 471 patients with T1D and 474 healthy siblings, was performed. Participants were volunteers from the Germans Trias i Pujol Hospital and DiabetesCero Foundation. Parents of children enrolled in the study completed a questionnaire that included questions about weeks of gestation, preterm delivery risk, weight at birth, and prenatal betamethasone exposure of their children. Multiple logistic regression was used to detect the association between betamethasone exposure and T1D.

RESULTS

We compared T1D prevalence between subjects prenatally exposed or unexposed to betamethasone. The percent of children with T1D in the exposed group was 37.5% (21 of 56), and in the unexposed group was 49.52% (410 of 828) (p = 0.139). The percentage of betamethasone-treated subjects with T1D in the preterm group (18.05%, 13 of 72) was significantly higher than that found in the control group (12.5%, 9 of 72) (p = 0.003). The odds ratio for T1D associated with betamethasone in the univariate logistic regression was 0.59 (95% confidence interval, 0.33; 1.03 [p = 0.062]) and in the multivariate logistic regression was 0.83 (95% confidence interval, 0.45; 1.52 [p = 0.389]).

CONCLUSIONS

The results demonstrate that the prenatal exposure to betamethasone does not increase T1D susceptibility, and may even be associated with a trend towards decreased risk of developing the disease. These preliminary findings require further prospective studies with clinical data to confirm betamethasone exposure effect on T1D risk.

Primipaternities and human birthweights

OBJECTIVES

To investigate in singleton multiparous pregnancies the effect of having a new father for an index pregnancy on new-borns' birthweights and intrauterine growth restriction.

DESIGN

20 year-observational cohort study (2001-2020).

SETTINGS

Centre Hospitalier Universitaire Hospitalier Sud Reunion's maternity (French overseas department, Indian Ocean).

MAIN OUTCOMES AND MEASURES

Comparing the 811 multiparas (cases) who had a new partner with the 49,712 who did not (controls), there were no differences concerning maternal age, education, ovulation induction/IVF, previous miscarriages, exams during pregnancies, pre-pregnancy BMI, gestational diabetes, and chronic hypertension. Cases had more previous pregnancies than controls (gravidity 4.2 vs 2.8, p < 0.001), volunteer abortions (OR1.93, p < 0.001), in vitro fecundations (OR 4.34, p < 0.001), were more likely to be unmarried (OR 2.94, p < 0.001) smoker (OR 2.2, p < 0.0001) and consuming alcohol during pregnancy (OR 2.35, p = 0.001). Cases had a much higher risk of preeclampsia than controls (OR 3.94, p < 0.001), especially early-onset preeclampsia (< 34 weeks) with an OR 4.1 (p < 0.001). Controlling for confounding factors (preeclampsia, smoking, alcohol use, early prematurity < 33 weeks, maternal ethnicity), primipaternity was an independent factor for small for gestational age newborns (OR 1.48, p < 0.001).

CONCLUSIONS

It has been known for decades that primiparas have lighter babies than multiparas. Primipaternity represents also a risk for lower birth weights. Human birthweight seems to be linked with a "couple habituation" (to paternal genes) which may be not fully established in the first pregnancy of the couple.

Birth weight increases with birth order despite decreasing maternal pregnancy weight gain

AIM

We investigated whether birth order is an influencing factor for birth weight independent from maternal factors.

METHODS

Data were obtained from the longitudinal cohort study LIFE Child and included 1864 children, of which 526 were only children. The 1338 siblings were ranked into first-borns (n = 570), second-borns (n = 606) and third-or-later-borns (n = 162). Children born prematurely, suffering from chronic or syndromic diseases, were excluded. We performed intra-family comparisons to reduce bias and assessed the impact of perinatal parameters, such as birth order on birth weight, using mixed models.

RESULTS

Birth weight increased with birth order. In univariate analyses, birth order had a significant effect on birth weight-SDS with second-borns having 0.29 SDS (app. 130 g) and third-borns 0.40 SDS (app. 180 g) higher values than first-borns (P < .001). Maternal pregnancy weight gain was associated with higher birth weight-SDS (P < .01) in univariate analysis, though maternal pregnancy weight gain was lower for higher birth orders. Multivariate analyses revealed that being a second or third-or-later-born child had a stronger impact on birth weight than all maternal factors.

CONCLUSION

Birth order must be considered a potential risk factor for higher birth weight. Maternal pregnancy weight gain is not the driving factor for higher birth weight in siblings.

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

Background

Nulliparity 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.

Methods

This 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.

Results

Multiparity 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.

Conclusion

Multiparity 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.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03718-4.

Associations of Vitamin D Deficiency, Parathyroid hormone, Calcium, and Phosphorus with Perinatal Adverse Outcomes. A Prospective Cohort Study

Vitamin D deficiency during pregnancy has been linked to perinatal adverse outcomes. Studies conducted to date have recommended assessing interactions with other vitamin D-related metabolites to clarify this subject. We aimed to evaluate the association of vitamin D deficiency during early pregnancy with preterm birth. Secondary outcomes included low birth weight and small for gestational age. Additionally, we explored the role that parathyroid hormone, calcium and phosphorus could play in the associations. We conducted a prospective cohort study comprising 289 pregnant women in a hospital in Granada, Spain. Participants were followed-up from weeks 10-12 of gestation to postpartum. Serum 25-hydroxyvitamin D, parathyroid hormone, calcium, and phosphorus were measured within the first week after recruitment. Pearson's χ² test, Mann-Whitney U test, binary and multivariable logistic regression models were used to explore associations between variables and outcomes. 36.3% of the participants were vitamin D deficient (<20 ng/mL). 25-hydroxyvitamin D concentration was inversely correlated with parathyroid hormone (ρ = -0.146, p = 0.013). Preterm birth was associated with vitamin D deficiency in the multivariable model, being this association stronger amongst women with parathyroid hormone serum levels above the 80th percentile (adjusted odds ratio (aOR) = 6.587, 95% CI (2.049, 21.176), p = 0.002). Calcium and phosphorus were not associated with any studied outcome. Combined measurement of 25-hydroxyvitamin D and parathyroid hormone could be a better estimator of preterm birth than vitamin D in isolation.

Is it worth reducing twins to singletons after IVF-ET? A retrospective cohort study using propensity score matching

INTRODUCTION

Many studies have shown that multifetal reduction of high-order multiple pregnancies results in improved pregnancy outcomes. However, whether conducting elective fetal reduction from dichorionic twins after in vitro fertilization (IVF) is worthwhile remains controversial. This study aimed to determine whether elective fetal reduction of dichorionic twins after IVF and embryo transfer (IVF-ET) is associated with increased take-home baby rate.

MATERIAL AND METHODS

This was a retrospective cohort study of 3600 dichorionic twin pregnancies after IVF-ET. The reduced group included 71 women with transvaginal elective fetal reduction between 7 and 8 weeks of gestation. The control group (n = 3529) comprised women who were managed expectantly. Propensity score matching was conducted before pregnancy outcomes were compared.

RESULTS

The take-home baby rate was significantly lower in the reduced group (83.1% vs 92.8%, P = 0.004). The total miscarriage rate was significantly higher in the reduced group (12.7% vs 6.2%, P = 0.04). Although preterm delivery rate was lower in the reduced group (P < 0.001), over 90% were over 32 weeks, whereas the proportions were equal in the reduced group.

CONCLUSIONS

In dichorionic twin pregnancies after IVF-ET, elective fetal reduction to singleton significantly decreased the chance of taking home live babies.

Alcohol binge drinking in early pregnancy and the effect on fetal growth: a cohort study

INTRODUCTION

Alcohol binge drinking is common in early pregnancy and is a well-established risk factor for subsequent child health. Yet, very few studies have investigated the effect on fetal growth. Furthermore, it has been speculated that the timing of binge drinking may be a determining factor for neonatal growth. The objective of this study was to assess the potential effect of binge drinking and different drinking patterns (timing and number of binge drinking episodes) in early pregnancy on fetal growth estimated by birthweight and birth length.

MATERIAL AND METHODS

From 1 March to 31 August 2000, 1836 pregnant Danish women from Aarhus University Hospital and Fredericia Hospital were included in the study and interviewed around the early second trimester about their drinking habits during their pregnancy. Information on anthropometric measures at birth was obtained from the Danish Medical Birth Registry. The potential effect of binge drinking and different drinking patterns was estimated using a multivariate general linear regression model adjusted for potential confounders that were selected a priori based on the currently available scientific literature.

RESULTS

The women who reported any binge drinking gave birth to children with a reduction in birth length of -0.02 cm (95% CI -0.23 to 0.18) and an increase in birthweight of 0.2 g (95% CI -42.8 to 43.2). The number of binge episodes and the timing of these episodes were also not associated with fetal growth.

CONCLUSIONS

The study suggests that binge drinking and different drinking patterns in early pregnancy do not affect fetal growth.

The impact of delayed maternity on foetal growth in Spain: An assessment by population attributable fraction

BACKGROUND

Delayed childbearing is considered a risk factor for maternal-foetal health. As in other higher-income countries, in Spain age at maternity has steadily increased during the last two decades.

AIM

To quantify the impact of the delay in the age at maternity on small for gestational age (SGA) categories of <3rd, 3rd-5th and 5th-10th percentiles.

METHODS

2,672,350 singleton live births born to Spanish mothers in 2007-2015 were analysed. Adjusted relative risk was calculated to estimate the adjusted partial population attributable fractions (PAF_p) for mothers aged 35-39 and ≥40 years for each category of SGA considering the interaction between age at maternity and parity.

FINDINGS

Primipara 35-39 years old mothers have the highest PAF_p in the three categories of SGA, with the maximum value for SGA <3rd percentile (2.57%, 95% CI 2.25, 2.88). PAF_p for both primipara and multipara ≥40 years old mothers were less than 1%. PAF_p for primipara older mothers increased significantly in 2007-2015 for the three categories of SGA, more clearly among those aged 35-39 years. The contribution of multipara mothers of both age groups did not increase significantly during the period.

CONCLUSION

Delayed maternity is a significant adjusted risk factor for SGA, contributing to the increase of its prevalence. However, results also suggest a limited clinical impact of delayed maternity on foetal growth. Positive changes in maternal profile associated with the shift in maternal age might contribute to explain the limited impact of mothers aged 35 years and older on negative birth outcome in Spain.