Reference Values for Birth Weight in Relation to Gestational Age in Poland and Comparison with the Global Percentile Standards.

INTRODUCTION: Percentiles of birth weight by gestational age (GA) are an essential tool for clinical assessment and initiating interventions to reduce health risks. Unfortunately, Poland lacks a reference chart for assessing newborn growth based on the national population. This study aimed to establish a national reference range for birth weight percentiles among newborns from singleton deliveries in Poland. Additionally, we sought to compare these percentile charts with the currently used international standards, INTERGROWTH-21 and WHO. MATERIALS AND METHODS: All singleton live births (n = 3,745,239) reported in Poland between 2010 and 2019 were analyzed. Using the Lambda Mu Sigma (LMS) method, the Generalized Additive Models for Location Scale, and Shape (GAMLSS) package, smoothed percentile charts (3-97) covering GA from 23 to 42 weeks were constructed. RESULTS: The mean birth weight of boys was 3453 ± 540 g, and this was higher compared with that of girls (3317 ± 509 g). At each gestational age, boys exhibited higher birth weights than girls. The weight range between the 10th and 90th percentiles was 1061 g for boys and 1016 g for girls. Notably, the birth weight of Polish newborns was higher compared to previously published international growth standards. CONCLUSION: The reference values for birth weight percentiles established in this study for Polish newborns differ from the global standards and are therefore useful for evaluating the growth of newborns within the national population. These findings hold clinical importance in identifying neonates requiring postbirth monitoring.

Longer duration of gestation in term singletons is associated with better infant neurodevelopment.

BACKGROUND: Longer gestation at term and post-term age is associated with increased perinatal mortality. Nonetheless, recent neuroimaging studies indicated that longer gestation is also associated with better functioning of the child's brain. AIMS: to assess whether longer gestation in term and post-term (in short: term) singletons is associated with better infant neurodevelopment. STUDY DESIGN: cross-sectional observational study. SUBJECTS: Participants were all singleton term infants (n = 1563) aged 2-18 months of the IMP-SINDA project that collected normative data for the Infant Motor Profile (IMP) and Standardized Infant NeuroDevelopmental Assessment (SINDA). The group was representative of the Dutch population. OUTCOME MEASURES: Total IMP score was the primary outcome. Secondary outcomes were atypical total IMP scores (scores <15th percentile) and SINDA's neurological and developmental scores. RESULTS: Duration of gestation had a quadratic relationship with IMP and SINDA developmental scores. IMP scores were lowest at a gestation of 38·5 weeks, SINDA developmental scores at 38·7 weeks. Next, both scores increased with increasing duration of gestation. Infants born at 41-42 weeks had significantly less often atypical IMP scores (adjusted OR [95 % CI]: 0·571 [0·341-0·957] and atypical SINDA developmental scores (adjusted OR: 0·366 [0·195-0·688]) than infants born at 39-40 weeks. Duration of gestation was not associated with SINDA's neurological score. CONCLUSIONS: In term singleton infants representative of the Dutch population longer gestation is associated with better infant neurodevelopment scores suggesting better neural network efficiency. Longer gestation in term infants is not associated with atypical neurological scores.

Comparing two different placental transfusion strategies for very preterm infants at birth: a matched-pairs study.

OBJECTIVE: To evaluate the clinical outcomes of using the extra-uterine placental transfusion (EPT) approach in very preterm infants (VPIs, gestational age <32 weeks) and compare this to delayed cord clamping (DCC) after birth. METHODS: In this matched pairs study, we compared the clinical outcomes of the EPT group to those of the DCC group. EPT were performed in fifty-three VPIs, of whom 27 were singletons and 25 were twins. The singleton VPIs were matched for gestational age (±5 days) and delivery mode, and the twin VPIs were matched between each other with the first twin subjected to DCC and the second twin to EPT. Data on the infants were collected and analysed as an overall group. A twin subgroup consisting of DCC and EPT groups was also analysed separately. The primary study outcome was either death or major morbidities. RESULTS: In total, 100 infants were included (n = 50 EPT group, n = 50 DCC group). The gestational ages of the DCC and EPT groups were (29.16 ± 1.76) and (29.12 ± 1.84) weeks, respectively. There were no differences in either deaths or major morbidities and other clinical outcomes, including the resuscitation variables, haemoglobin levels and red blood cell transfusion, between the two groups. In twin subgroups (gestational age 29.05 ± 1.89 weeks), EPT was associated with a higher rate of necrotizing enterocolitis (NEC) when compared with DCC (odds ratio = 7 (95% CI, 1.06 to 56.89), p = 0.031). CONCLUSIONS: In twin subgroups, the incidence of NEC was higher in the EPT group when compared to the DCC group and therefore based on an abundance of caution the use of EPT in very preterm twins is not recommended.

Extra-uterine placental transfusion (EPT) is an alternative new form of placental transfusion. It can alleviate the problem of delayed respiratory support during DCC. It can also be performed in some placental abruption cases.EPT may lead to the same clinical outcome as DCC in singleton pregnancies but based on an abundance of caution it is not recommended for very preterm twins.

Effects of gestational diabetes mellitus and assisted reproductive technology treatment on the risk of preterm singleton birth.

Background: Although assisted reproductive technology (ART) plays a critical role in reducing infertility, ART pregnant women are reported at higher risk of preterm birth (PTB). Besides, women undergoing ART encounter a higher risk of developing gestational diabetes mellitus (GDM). However, existing studies on the combined effect of ART treatment and GDM on PTB risk are sparse. Methods: This population-based retrospective cohort study used nationwide birth certificate data from the US National Vital Statistics System 2015-2019. All mothers who had a singleton live birth without pre-pregnancy diabetes were included. Multivariable logistic regression models were used to estimate the odds ratio (OR) of PTB. Results: We finally included 18,140,241 American mother-infant pairs. The overall rate of PTB was 7.92% (n = 1,436,328). The PTB rate for non-ART mothers without GDM, ART mothers without GDM, non-ART mothers with GDM, and ART mothers with GDM were 7.67, 10.90, 11.23, and 14.81%, respectively. The incidence of GDM in ART mothers (10.48%) was significantly higher than in non-ART mothers (6.26%). After adjusting for potential confounders, compared with non-ART mothers without GDM, the PTB risk was significantly increased for ART mothers without GDM (AOR: 1.47, 95% CI 1.44-1.50), non-ART mothers with GDM (AOR:1.35, 95% CI 1.34-1.36) and ART mothers with GDM (AOR: 1.82, 95% CI 1.74-1.90) respectively, showing an increasing tendency. This phenomenon was stable among mothers in all groups of mothers older than 25 years. Conclusion: To prevent PTB, effective approaches for the prevention of GDM are crucial to mothers who conceived through ART.

The association between maternal complications and small for gestational age in twin pregnancies using singleton and twin birth weight references.

INTRODUCTION: In singleton pregnancies, maternal complications, such as preeclampsia and thyroid dysfunction are associated with small for gestational age (SGA). However, data on the association between SGA and maternal complications in twin pregnancies are limited and conflicting. Small sample size and the application of singleton birth weight reference (SBWR) to define SGA in twins may be reasons for the inconsistent conclusions. Purpose of this study was to define SGA in dichorionic diamniotic (DCDA) and monochorionic diamniotic (MCDA) twin pregnancies using both SBWR and twin birth weight reference (TBWR) and to determine whether certain maternal complications are associated with SGA in twin pregnancies. MATERIALS AND METHODS: This retrospective cohort study included all twins delivered in a single tertiary center between 2013 and 2018. SGA was defined as a twin with birth weight <10th centile for gestational age using either SBWR or TBWR. The association between SGA and maternal complications was analyzed separately for DCDA and MCDA twin pregnancies, expressed as odds ratio (OR) and adjusted odds ratio (aOR) with 95% confidence interval (95%-CI). RESULTS: A total of 2005 DCDA and 467 MCDA twin pregnancies were enrolled. In DCDA pregnancies, SGA was significantly associated with PE according to TBWR (22.73 vs. 14.56%, aOR 1.823, 95%-CI 1.137-2.922). This association was even more pronounced between SGA and severe PE (9.09 vs. 4.54%, aOR 2.234, 95%-CI 1.115-4.479). In turn, PE was associated with higher risk of SGA defined according to TBWR (8.31 vs. 4.99%, aOR 1.825, 95%-CI 1.139-2.925). No association was detected between SGA and other maternal complications. Using SBWR, no association was found between preeclampsia and SGA. In MCDA pregnancies, according to TBWR, SGA was associated only with severe PE (12.5 vs. 4.06%, aOR 3.470, 95%-CI 1.256-9.587) and lower risk of PROM (aOR 0.067, 95%-CI 0.014-0.322). CONCLUSION: PE was associated with SGA in DCDA pregnancies only when TBWR was used, suggesting that DCDA pregnancies complicated with PE should be closely monitored for signs of SGA and vice versa. In MCDA pregnancies, SGA defined according to TBWR was associated with only severe PE (but not with all PE) and lower risk of PROM. More basic experiments are needed to investigate the mechanisms underlying PE and SGA in DCDA and MCDA twin pregnancies respectively.

Speech and language development of children born following assisted reproductive technologies.

OBJECTIVES: Studies which targeted communication skills of children born following assisted reproductive technologies have reported contradictory results. Concerning the increasing rates of children born in these technologies and the importance of some factors as risk factors like birth weight, gestational age, and the number of children per birth in these procedures, studying speech and language skills is critical. So, the current study aimed to investigate the speech and language capabilities of Persian speaking children born following these procedures. METHODS: A descriptive and cross-sectional study was carried out in Babol city in 2016-2017 to investigate the receptive and expressive language and speech of Persian speaking children born in assisted reproductive technologies in the age range of 6-72 months. Parents of 78 children completed the Newsha Developmental Scale to assess language and speech skills. Then, the language and speech performance of the participants were compared in terms of gestational age, birth weight, number of children per birth, and sex in the current research and they are categorized as normal or having delay in language and speech development. RESULTS: The participants had statistically significant difference for the receptive language in terms of gestational age (χ2 (1) = 5.76, p = 0.01) and birth weight (χ2 (1) = 8.22, p = 0.004) but in terms of the number of children per birth (χ2 (1) = 7.11, p = 0.009) and sex (χ2 (1) = 0.037, p = 0.84) did not have statistically significant difference. The children did not show significant difference for the expressive language in terms of gestational age (χ2 (1) = 1.09, p = 0.29), birth weight (χ2 (1) = 0.34, p = 0.55), the number of children per birth (χ2 (1) = 1.58, p = 0.2), and sex (χ2 (1) = 0.037, p = 0.84). The participants of the present study did not have statistically significant difference in speech in terms of gestational age (χ2 (1) = 2.82, p = 0.09), the number of children per birth (χ2 (1) = 3.57, p = 0.06), and sex (χ2 (1) = 0.06, p = 0.79). They had significant difference in speech only in terms of birth weight (χ2 (1) = 4.13, p = 0.04). CONCLUSION: Based on the results of the administration of the Newsha Developmental Scale as a screening tool, it seems that some factors like sex and number of children per birth do not affect speech and language performance of children born following ART. Another factor including gestational age and birth weight had effects on some domains. It is essential to design longitudinal studies to follow the speech and language performance of this population.

Embryo cryopreservation and preeclampsia risk.

OBJECTIVE: To determine whether assisted reproductive technology (ART) cycles involving cryopreserved-warmed embryos are associated with the development of preeclampsia. DESIGN: Retrospective cohort study. SETTING: IVF clinics and hospitals. PATIENT(S): A total of 15,937 births from ART: 9,417 singleton and 6,520 twin. INTERVENTION(S): We used linked ART surveillance, birth certificate, and maternal hospitalization discharge data, considering resident singleton and twin births from autologous or donor eggs from 2005-2010. MAIN OUTCOME MEASURE(S): We compared the frequency of preeclampsia diagnosis for cryopreserved-warmed versus fresh ET and used multivariable logistic regression to adjust for confounders. RESULT(S): Among pregnancies conceived with autologous eggs resulting in singletons, preeclampsia was greater after cryopreserved-warmed versus fresh ET (7.51% vs. 4.29%, adjusted odds ratio = 2.17 [95% CI 1.67-2.82]). Preeclampsia without and with severe features, preeclampsia with preterm delivery, and chronic hypertension with superimposed preeclampsia were more frequent after cryopreserved-warmed versus fresh ET (3.99% vs. 2.55%; 2.95% vs. 1.41%; 2.76 vs. 1.48%; and 0.95% vs. 0.43%, respectively). Among pregnancies from autologous eggs resulting in twins, the frequency of preeclampsia with severe features (9.26% vs. 5.70%) and preeclampsia with preterm delivery (14.81% vs. 11.74%) was higher after cryopreserved versus fresh transfers. Among donor egg pregnancies, rates of preeclampsia did not differ significantly between cryopreserved-warmed and fresh ET (10.78% vs. 12.13% for singletons and 28.0% vs. 25.15% for twins). CONCLUSION(S): Among ART pregnancies conceived using autologous eggs resulting in live births, those involving transfer of cryopreserved-warmed embryos, as compared with fresh ETs, had increased risk for preeclampsia with severe features and preeclampsia with preterm delivery.

Impact of monozygotic twinning on multiple births resulting from in vitro fertilization in the United States, 2006-2010.

OBJECTIVE: To determine the contribution of monozygotic twining to in vitro fertilization multiple births. STUDY DESIGN: We performed a retrospective analysis of the incidence of monozygotic twining in multiple births resulting from fresh embryo transfers using 2006-2010 data from the Society for Reproductive Technology Clinic Outcome Reporting System. RESULTS: The number of embryos transferred were fewer than the number of births in 0.5% (223/40950) of twin, 29% (659/2289) of triplet, and 64% (43/67) of quadruplet births resulting from transfer of fresh embryos from 2006 to 2010. In 2010, 37% of triplets and 100% of quadruplet births occurred when fewer than 3 and fewer than 4 embryos respectively were transferred. CONCLUSION: Monozygotic twinning plays a key role in the development of triplet and quadruplet pregnancies achieved through in vitro fertilization.

Intimate partner violence and the association with very preterm birth.

BACKGROUND: Intimate partner violence is a major public health problem. It occurs commonly in pregnancy, resulting in adverse events for women and their fetus or children. The objective of this study was to examine the association between intimate partner violence and very preterm birth. METHODS: This population-based, case-control study was conducted in Victoria, Australia, from 2002 to 2004. Interviews were conducted with 603 women who had a singleton very preterm birth (20-31 weeks' gestation), 770 women who had a singleton term birth (37 or more completed weeks' gestation), 139 women who had a very preterm twin birth, and 214 women who had a term twin birth. Intimate partner violence was measured using the Composite Abuse Scale, and questions were also asked about fear of partners and violence from others. RESULTS: Prevalence of intimate partner violence in the past 12 months was 14.9 percent in singleton case women, 11.7 percent in singleton control women, 9.5 percent in twin case women, and 14.7 percent in twin control women. Fear of a previous partner and reporting similar violence experience with someone else were more likely in singleton births (AOR = 1.36; 95% CI 1.03, 1.79) and (AOR = 1.44; 95% CI 1.12, 1.86), respectively. No differences between twin case women and twin control women were observed. When the precipitating cause of very preterm birth was investigated, antepartum hemorrhage was significantly associated with intimate partner violence and all its subscales. CONCLUSIONS: The heterogeneity of causes of very preterm birth may explain the lack of association found with intimate partner violence in pregnancy. Pregnant women have a significant risk of intimate partner violence, which should be a serious concern for all care providers.