Pattern of human blood spermidine and spermine in prematurity

Blood polyamines have been determined in preterm newborns (24-37 gestation weeks) during the first hours of life and until 20 days after birth. The most elevated polyamine concentrations were found in preterm newborns from the 24th-33rd gestational week. In all preterms, however, polyamine concentrations are higher than in full term newborns. In preterm infants two different patterns of blood polyamines appear in relation to the gestational age: in infants born at 24-34 wk, spermidine reaches the peak at 12 h and spermine shows high concentrations between 12 and 48 h. In infants born at 35-37 wk maximal concentrations of polyamines were reached at 12 h. Successively, in both groups the polyamines progressively decrease up to the 20th day, with some individual variations. Our results may provide a further support to the suggestion of a fetal genesis of polyamines and their involvement in fetal growth.     

未足月胎膜早破的临床处理对妊娠结局的影响

目的分析未足月胎膜早破的临床处理对妊娠结局的影响。方法将144例未足月胎膜早破患者根据孕周不同分为28~33孕周组(66例)和34~36孕周组(78例),根据孕周对其进行不同的处理。比较两组的治疗效果。结果两组入院后48 h的hs-CPR、CPR、IL-6、IL-8水平均升高,入院后72 h均降低,且34~36孕周组不同时间点上述指标水平均低于28~33孕周组(P<0.05)。两组潜伏期>48 h的母婴结局均比潜伏期≤48 h差。28~33孕周组潜伏期≤48 h的剖宫产率和潜伏期>48 h的新生儿呼吸窘迫发生率均高于34~36孕周组同潜伏期(P<0.05)。结论对妊娠28~33周胎膜早破患者给予期待保胎治疗,适当延长潜伏期,可提高胎儿娩出存活率,但要根据母婴情况适时结束妊娠,以降低不良母婴结局;对妊娠34~36周的胎膜早破且胎肺成熟者,应在48 h内结束妊娠,缩短潜伏期,以减少不良妊娠结局。     

Low‐molecular‐weight heparin added to aspirin in the prevention of recurrent early‐onset pre‐eclampsia in women with inheritable thrombophilia: the FRUIT‐RCT

Summary. Background: Early‐onset hypertensive disorders (HD) of pregnancy and small‐for‐gestational age infants (SGA) are associated with placental vascular thrombosis, these often recur and are also associated with inheritable thrombophilia. Aspirin reduces the recurrence risk. Objectives: Adding low‐molecular‐weight heparin (LMWH) to aspirin at < 12 weeks gestation reduces the recurrence of HD in women with previous early‐onset HD (pre‐eclampsia, hemolysis, elevated liver enzymes and low platelets [HELLP] syndrome and eclampsia) and/or SGA, in the context of inheritable thrombophilia without antiphospholipid antibodies. Patients/methods: In a multicenter randomized control trial (RCT), 139 women included were < 12 weeks gestation. Inclusion criteria: previous delivery < 34 weeks gestation with HD and/or SGA; inheritable thrombophilia (protein C deficiency, protein S deficiency, activated protein C resistance, factor V Leiden heterozygosity and prothrombin gene G20210A mutation heterozygosity); and no antiphospholipid antibodies detected. Intervention: either daily LMWH (dalteparin, 5000 IU weight‐adjusted dosage) with aspirin 80 mg or aspirin 80 mg alone. Main outcome measures: Primary outcomes: recurrent HD onset (i) < 34 weeks gestation and (ii) irrespective of gestational age. Secondary outcomes: recurrent SGA, preterm birth, maternal/neonatal hospitalization, spontaneous abortion and individual HD. Analysis by intention‐to‐treat. Results: Low‐molecular‐weight heparin with aspirin reduced recurrent HD onset < 34 weeks gestation (risk difference [RD] 8.7%: confidence interval [CI] of RD 1.9–15.5%; P = 0.012; number needed to treat [NNT] 12). Recurrent HD irrespective of gestational age was not different between the arms. No women withdrew as a result of adverse effects. Trial Registration: http://www.isrctn.org ) (isrctn87325378). Conclusions: Adding LMWH to aspirin at < 12 weeks gestation reduces recurrent HD onset < 34 weeks gestation in women with inheritable thrombophilia and prior delivery for HD/SGA <34 weeks. However, close monitoring of the mother and fetus remains important throughout pregnancy.     

The use of a variable cut-off value of cervical length in women admitted for preterm labor before and after 32 weeks.

OBJECTIVE: To determine whether the optimal cut-off value to predict low risk of preterm delivery in women admitted for preterm labor should be adjusted for gestational age. METHODS: A cohort of 333 women with singleton pregnancies admitted with preterm labor and intact membranes between 24 and < 36 weeks' gestation was studied. The women were categorized according to prematurity into one of two groups: those admitted at < 32 weeks (Group 1, very preterm) and those admitted at >or= 32 weeks (Group 2, preterm). Transvaginal ultrasound was performed 24-48 h after admission and cervical length measured. The predictive value of different cut-off points was explored. Outcome variables were spontaneous preterm delivery within 7 days of admission and delivery at < 34 weeks. RESULTS: The mean ( +/- SD) gestational ages at admission and delivery were 31.9 ( +/- 2.6) and 37.5 ( +/- 2.2) weeks, respectively, and the mean ( +/- SD) cervical length was 30.4 ( +/- 8.9) mm. The rates of spontaneous delivery within 7 days and at < 34 weeks were 6.3 and 7.0%, respectively. The cut-off value of 15-mm cervical length showed a sensitivity, negative predictive value and false positive rate for delivery within 7 days of 0, 96.5 and 2.7% in the very preterm group, and 35.3, 94.6 and 4% in the preterm group, respectively. For a cut-off point of 25 mm, these values were 75, 99 and 14.3%, and 70.6, 96.8 and 24.5%. CONCLUSIONS: The predictive value of different cut-off points of cervical length is similar at different gestational ages. However, the higher false positive rate after 32 weeks' gestation might justify the adoption of gestational-age related cut-off values in clinical protocols. In women admitted at < 32 weeks' gestation, a cut-off point of 25 mm may be used to predict a low risk of preterm delivery, whereas in women admitted at 32 weeks or later, 15 mm might be more appropriate. Published by John Wiley & Sons, Ltd.     

Physiological vital sign differences between well newborns greater than 34 weeks gestation: A pilot study

BackgroundNewborns have their vital signs measured as part of routine care. However, there is inconsistency in accepted physiological ranges for well newborns beyond the post-delivery stabilisation period which has implications for the identification of illness.ObjectiveTo explore differences in physiological vital signs between three gestational age groups: late preterm (34⁺⁰ - 36⁺⁶), early term (37⁺⁰–38⁺⁶) and term (≥39⁺⁰) weeks gestation.DesignA single site prospective observational study.SettingA postnatal ward and special care baby unit in a major tertiary hospital in Australia.ParticipantsNewborns from 34 weeks gestation admitted to either the postnatal ward or special care baby unit.MethodsHeart rate, respiratory rate and oxygen saturation were continuously monitored for up to 6 h. Newborn temperature and blood pressure were measured twice during the monitoring period.ResultsContinuous monitoring resulted in 284,542 heart rate, 275,826 respiratory rate, 287,572 SpO₂ values, and 60 temperature and 60 blood pressure data points. Heart rate was significantly different between gestational age groups with late preterm heart rates 13.4 bpm (95% CI 6.5–20.4) higher than term newborns. Early term heart rates were 2.3 bpm (95% CI -4.6 – 9.3) higher than term newborns, although not statistically significantly different. Heart rate was significantly different based on sex with females on average 7.7 beats per minute (bpm) (95% CI 1.9–13.5) higher than males.Respiratory rate was not significantly different between gestational age groups however, on average, was −2.0 respiration rate per minute (rpm) (95% CI -6.8 – 2.7) lower for late preterm babies and −1.3 rpm (95% CI -6.0 – 3.4) lower for early term babies compared to term newborns. SpO₂ was not significantly different between gestational age groups, however, on average was −1.17 log units (95% CI -2.32 to −0.01) lower for late preterm newborns and −1.00 log units (95% CI -2.16 – 0.15) lower for early term newborns compared to term newborns. Respiratory rate and SpO₂ were neither clinically nor statistically significantly different by sex.There were no significant differences between gestational age groups for temperature (p = 0.38) or blood pressure (systolic p = 0.93, diastolic p = 0.54). No significant mean differences were observed based on sex for temperature (p = 0.57) or blood pressure (systolic p = 0.98, diastolic p = 0.40).ConclusionsThis study demonstrated a clinically significant higher heart rate in those born late preterm. This may have implications for current “one-size fits all” newborn early warning tools, as well as care of well late preterm infants in maternity units.     

Does transvaginal sonographic measurement of cervical length before 14 weeks predict preterm delivery in high-risk pregnancies?

OBJECTIVE: To determine whether high-risk patients manifest cervical length < 25 mm on transvaginal ultrasound before 14 weeks of gestation, and if this finding is predictive of preterm delivery. METHODS: Asymptomatic pregnancies at high risk for preterm birth were followed prospectively from 10 + 0 weeks to 13 + 6 weeks with transvaginal sonographic measurement of the cervix. A cervical length < 25 mm was considered a short cervix at this gestational age and at the follow-up ultrasound examinations, performed between 14 and 24 weeks. The primary outcome was preterm birth at < 35 weeks of gestation. RESULTS: One hundred and eighty-three pregnancies met the study criteria and were included in the analysis. Only 10 (5%) patients had a cervix < 25 mm before 14 weeks. The sensitivity, specificity and positive and negative predictive values of a short cervix were 14%, 97%, 50%, and 82%, respectively (relative risk, 2.8; 95% confidence interval, 1.4-5.6). The mean transvaginal sonographic cervical length before 14 weeks of gestation was 33.7 +/- 6.9 mm in pregnancies which delivered preterm (n = 36), and 35.0 +/- 6.8 mm in those delivering at term (n = 147) (P = 0.3). Follow-up transvaginal ultrasound examination of the cervix to 24 weeks revealed that the average gestational age at which a short cervix was detected was 18.7 +/- 2.9 weeks. CONCLUSION: A cervical length < 25 mm on transvaginal sonographic assessment rarely occurs before 14 weeks even in high-risk patients destined to deliver preterm; in these patients cervical changes predictive of preterm birth develop mostly after this gestational age.     

Does cervical length at 13-15 weeks' gestation predict preterm delivery in an unselected population?

OBJECTIVE: To assess the role of early mid-trimester cervical length measurement as a predictor of spontaneous preterm birth in an unselected population. METHODS: In this prospective study, unselected, asymptomatic, Caucasian women with singleton pregnancies underwent standardized transvaginal ultrasonographic (TVS) cervical length measurement at 13-15 weeks' gestation as a screening test for preterm delivery (PTD). Women with multiple gestations, iatrogenic PTD, and previous cervical conization were excluded. The primary outcome measures were spontaneous PTD at < 37 and < 34 weeks. The correlation between cervical length and previous obstetric history was evaluated. RESULTS: A total of 2469 patients met the inclusion criteria. The mean gestational age at cervical assessment was 14 + 2 weeks. The mean gestational age at delivery was 40 + 0 weeks. The rate of spontaneous deliveries before 37 weeks' gestation was 1.7%. In 0.2% the delivery occurred before 34 weeks' gestation. The mean +/- standard deviation cervical length for the entire population was 44.2 +/- 5.4 mm. No difference was observed between cervical length in women that delivered at term and those that delivered either before 37 or before 34 weeks' gestation. Previous obstetric history (prior preterm birth, previous miscarriages and terminations, and parity) did not affect cervical length at 14 weeks of gestation. CONCLUSIONS: Performed at 14 weeks' gestation, TVS measurement of the cervical canal length to predict spontaneous PTD is not a reliable screening procedure.     

2007－2018年浙江省义乌市新生儿出生体重变化趋势比较分析

目的分析2007—2018年浙江省义乌市新生儿出生体重变化趋势,并与不同标准进行比较,制订和更新适合目标人群的新生儿出生体重曲线。方法利用义乌市妇幼保健信息平台的数据,提取2007年1月至2018年6月记录的新生儿出生体重,分析出生体重变化趋势以及低出生体重儿和巨大儿发生率变化情况。 采用LMS方法计算出胎龄别出生体重百分位数参考值,运用GAMLSS模型绘制出生体重曲线;将本研究的胎龄别出生体重百分位数参考值与国内外研究进行对比。结果本研究共纳入了68 358名新生儿,其中男、女婴的平均出生体重分别为3 373 g和3 257 g。 男、女婴早产的比例分别为6.01%和5.04%,男婴早产比例显著高于女婴。 低出生体重儿和巨大儿分别占3.84%和7.43%。 出生胎龄33 ~ 41周的男婴出生体重均显著大于女婴出生体重。 随着出生胎龄的增长,出生体重也相应增加。 男婴出生胎龄为37 ~ 41周的胎龄别出生体重均大于2015年全国标准;33 ~ 41周的胎龄别出生体重均大于INTERGROWTH-21st的百分位数参考值。女婴出生胎龄为38 ~ 41周的胎龄别出生体重均大于2015年全国标准;33、35 ~ 41周的胎龄别出生体重均大于INTERGROWTH-21st 的百分位数参考值。结论2007—2018年义乌市男婴出生体重呈逐年下降趋势,女婴出生体重随年份变化趋势不显著。 本次研究提出了义乌市新生儿胎龄别出生体重参考值,分性别绘制了出生体重曲线参考。     

Association Between Second‐Trimester Cervical Length and Spontaneous Preterm Birth in Twin Pregnancies

Objective. The purpose of this study was to define normal second‐trimester cervical length (CL) measurements and to estimate the association between second‐trimester CL and spontaneous preterm birth (SPTB) in twin pregnancies. Methods. A retrospective cohort of 309 asymptomatic patients with twin pregnancies who had routine outpatient CL assessment in the second trimester was studied. We looked at the gestational age periods of 16 to 17 6/7, 18 to 19 6/7, 20 to 21 6/7, and 22 to 23 6/7 weeks. We estimated the association between the CL measurement during each period and SPTB. A short CL was defined both as a CL at or below the 10th percentile for gestational age and 25 mm or less. We also performed regression analyses controlling for a number of clinically important factors: maternal age, chorionicity, in vitro fertilization, multifetal reduction, prior term births, prior preterm births, prepregnancy body mass index, and cerclage. Results. The CL measurement at 16 to 17 6/7 weeks was not associated with gestational age at delivery or SPTB. At 18 to 19 6/7 and 20 to 21 6/7 weeks, the CL measurement was not significantly associated with gestational age at delivery or SPTB before 28 and 32 weeks. There was an association with SPTB before 35 weeks. At 22 to 23 6/7 weeks, the CL measurement had a significant association with gestational age at delivery and SPTB before 28, 32, and 35 weeks (P < .05). A short CL at 22 to 23 6/7 weeks was significantly associated with SPTB before 32 and 35 weeks (P < .05). Conclusions. In second‐trimester twin pregnancies, the strongest association between CL and SPTB is at 22 to 23 6/7 weeks.     

Maturation of the Cardiac Response to Sound in High-Risk Preterm Infants

Noise is considered a potential source of stress in the neonatal intensive care unit (NICU); yet, it is unknown how preterm infants habituate to sound in the NICU. Heart rate responses to sound were evaluated in 12 preterm infants from 32 weeks' gestational age through hospital discharge. Heart rate response changes to auditory stimuli were recorded for 10 habituation and 10 dishabituation trials. Significant heart rate deceleration began to appear by 34 weeks postconceptional age. With weeks 32 to 38 combined, a significant response was noted for the novel response. Responses differed significantly for weeks 34, 35, and 36. Infants at 36 weeks had a significant heart rate response at T17 to T20, suggesting anticipation of a third stimulus. Infants with higher Apgar 5 scores had smaller heart rate responses. Findings suggest that preterm infants, especially those with lower Apgar scores, may be vulnerable to larger heart rate changes in response to sound and may require additional consideration.     

Establishment of reference intervals for thyroid hormones in premature infants beyond the first week of life using Beckman Coulter Unicel DxI 800

BackgroundThis 4-year retrospective cohort study aimed to establish reference intervals for free triiodothyronine (FT3), free thyroxine (FT4), and thyrotropin (TSH) in premature infants using the Beckman Coulter Unicel DxI 800 automated immunoassay system.MethodsStudy subjects included 605 preterm infants with a gestational age of 26–36 weeks (corrected: 29–38 weeks). Pearson correlation was used to evaluate the association between hormone levels and gestational and corrected gestational ages. A nonparametric method was used to establish reference intervals based on corrected gestational age.ResultsFT3 and FT4 levels were positively correlated with gestational and corrected gestational ages, respectively. TSH levels were slightly negatively correlated with gestational and corrected gestational ages. FT3 significantly differed according to corrected gestational age (29–33 weeks vs 34–38 weeks); however, the difference was smaller than the reference change value (RCV) for the FT3 test. Thus, we combined the FT3 reference intervals into a single reference interval: 2.65–4.93 pmol/L (29–38 weeks). The reference intervals of FT4 and TSH were 11.20–24.97 pmol/L (29–38 weeks) and 1.01–10.14 mIU/L (29–38 weeks), respectively.ConclusionsUnlike those of full-term infants or adults, the reference intervals established in this study are applicable in premature infants. These results highlight the importance and complexity of establishing instrument-specific thyroid hormone reference intervals for preterm infants.     

Clinical outcomes for babies born between 27 – 31 weeks of gestation: Should they be regarded as a single cohort?

Preterm babies born between 27 and 31 weeks of gestation are understudied and historically, have been grouped as a single cohort. Increased evidence relating to clinical outcomes is shaping models of care for babies born ≤26 weeks of gestation. Similar consideration of births between 27 and 31 weeks of gestation is now warranted. To address this, a clear understanding of the impact of progressive maturation in utero on the clinical care required, and on neonatal and infant outcomes of this group of preterm babies is helpful.In this review we highlight the spectrum of clinical presentations for babies born at 27–31 weeks of gestation. We discuss this with respect to key stages of organ/system development occurring in-utero during this five-week period and reveal a consistent trend of decreasing incidence of mortality and major morbidity with increasing gestational age at birth from 27 to 31 weeks. The clinical care required and the outcomes between babies born at either end of this gestational age range appear to be substantially different. This suggests it may be more appropriate to report outcomes by week of gestation rather than as a group in future research. Preterm health service delivery providers and decision makers need to consider this in planning services for the future, especially in environments where neonatal intensive care resources ought to be optimised for those at greatest need.     

Neonatal pain in relation to postnatal growth in infants born very preterm

Procedural pain is associated with poorer neurodevelopment in infants born very preterm (≤ 32 weeks gestational age), however, the etiology is unclear. Animal studies have demonstrated that early environmental stress leads to slower postnatal growth; however, it is unknown whether neonatal pain-related stress affects postnatal growth in infants born very preterm. The aim of this study was to examine whether greater neonatal pain (number of skin-breaking procedures adjusted for medical confounders) is related to decreased postnatal growth (weight and head circumference [HC] percentiles) early in life and at term-equivalent age in infants born very preterm. Participants were n=78 preterm infants born ≤ 32 weeks gestational age, followed prospectively since birth. Infants were weighed and HC measured at birth, early in life (median: 32 weeks [interquartile range 30.7-33.6]) and at term-equivalent age (40 weeks [interquartile range 38.6-42.6]). Weight and HC percentiles were computed from sex-specific British Columbia population-based data. Greater neonatal pain predicted lower body weight (Wald χ(2)=7.36, P=0.01) and HC (Wald χ(2)=4.36, P=0.04) percentiles at 32 weeks postconceptional age, after adjusting for birth weight percentile and postnatal risk factors of illness severity, duration of mechanical ventilation, infection, and morphine and corticosteroid exposure. However, later neonatal infection predicted lower weight percentile at term (Wald χ(2)=5.09, P=0.02). Infants born very preterm undergo repetitive procedural pain during a period of physiological immaturity that appears to impact postnatal growth, and may activate a downstream cascade of stress signaling that affects later growth in the neonatal intensive care unit.     

Serial translabial sonographic measurement of cervical dimensions between 24 and 34 weeks' gestation in pregnant Thai women.

OBJECTIVE: To assess serial changes of cervical dimensions in pregnant Thai women between 24 and 34 weeks' gestation by translabial sonography. METHODS: A longitudinal study of cervical dimensions obtained by translabial sonography at 24, 28, 30, 32, and 34 weeks' gestation in 144 women was conducted. The gestational age at labor was recorded and women were defined as having preterm labor or term labor according to whether there was onset of true labor pain before or after 37 completed weeks, respectively. Cervical changes over time were analyzed by repeated ANOVA. The associations between cervical dimensions and gestational age, parity and prepregnancy body mass index were calculated by multiple linear regression analysis. RESULTS: Cervical length decreased whereas cervical width increased as gestational age advanced. Cervical length and width in women with term labor, but only cervical length in women with preterm labor, changed significantly throughout the period of 24-34 weeks' gestation (P < 0.01). The cervix was significantly longer in parous women and in women with a body mass index of more than 26 kg/m2, but was shorter in women of advanced gestational age. The cervix was significantly wider in parous women and in those of advanced gestational age. Weekly crude rate, adjusted for parity and prepregnancy body mass index, of both cervical length shortening and cervical width widening was 0.4 mm in women with term labor. Women with preterm labor had cervical shortening of 0.5 mm per week. CONCLUSIONS: Gestational age, parity and prepregnancy body mass index are significantly associated with the dynamic changes of cervical length and width in Thai women. These factors should be considered when assessing normal values of cervical dimensions and for predicting the risk of preterm delivery.     

How to identify twins at low risk of spontaneous preterm delivery.

OBJECTIVE: The aim of this study was to evaluate transvaginal sonographic assessment of cervical length at 23 weeks as a screening test for spontaneous preterm delivery in order to define a cut-off value that could be used to select twin pregnancies at low risk of spontaneous preterm delivery. METHODS: In a prospective multicenter study of 383 twin pregnancies included before 14 + 6 weeks a cervical scan with measurement of the cervical length was performed at 23 weeks' gestation. The results were blinded for the clinicians if the cervical length was > or = 15 mm. The rates of spontaneous delivery at different cut-off levels of cervical length were determined. RESULTS: Eighty-nine percent of the twins had dichorionic placentation and 58% were conceived after assisted reproduction. The rate of spontaneous preterm delivery was 2.3% (1.5% for dichorionic (DC) and 9.1% for (MC) monochorionic twins) before 28 weeks and 18.5% (17.1% for DC and 29.5% for MC twins) before 35 weeks. The screen-positive rate was 5% for a cervical length < or = 20, 7-8% at < or = 25, 16-17% at < or = 30 and 34-48% at < or = 35 mm depending on chorionicity. The false-negative rate (1 - negative predictive value) ranged from 1.2% at 28 weeks to 18.6% at 35 weeks for all twins. Receiver-operating characteristics curves showed that the sensitivity increased with declining gestational age with cut-off levels of highest accuracy at 21 mm for 28 weeks and 29 mm for 33 weeks. CONCLUSIONS: Cervical length measurement at 23 weeks of gestation is a good screening test for predicting twins at low risk of preterm and very preterm delivery, especially in DC twins. The present results suggest that a cut-off of 25 mm should be recommended.     

Gestational age-dependent changes in circulating hematopoietic stem cells in newborn infants

In the fetus, hematopoietic stem cells originate in the yolk sac and are believed to be transferred to all other hematopoietic organs via the circulation. In humans, the time course of this transfer has not been systematically evaluated in viable premature infants. We examined the cord blood of 13 preterm (25 to 36 weeks of gestation) and 10 term (38 to 42 weeks of gestation) infants for pluripotent (mixed colony-forming unit-granulocyte, erythrocyte, macrophage, megakaryocyte), erythroid (burst-forming unit-erythroid, colony-forming unit-erythroid) and myeloid (colony-forming unit-granulocyte, macrophage) stem cells. A gestational age-dependent decrease in all lineages of circulating hematopoietic stem cells was noted (p less than 0.001). By 34 weeks of gestation, preterm infant cord blood had a similar concentration of circulating stem cells compared with that of term infants. This gestational age-dependent decrease in hematopoietic stem cells of all lineages supports the hypothesis of a blood-borne transfer of hematopoiesis that appears largely complete by 34 weeks of gestation. Infants born after less than 32 weeks of gestation have high levels of circulating hematopoietic stem cells that may reflect the active transfer of hematopoiesis from liver to bone marrow.     

Qualitative venous Doppler flow waveform analysis in preterm intrauterine growth-restricted fetuses with ARED flow in the umbilical artery--correlation with short-term outcome.

OBJECTIVE: The aim of this retrospective study was to examine the significance of severe Doppler waveform abnormalities in the ductus venosus (DV) and the umbilical vein (UV) for the prediction of adverse outcomes in very preterm growth-restricted fetuses with absent or reversed end-diastolic flow in the umbilical artery (UA) at 24-34 weeks of gestation. METHODS: Seventy-four fetuses with intrauterine growth restriction (IUGR) and absent or reversed end-diastolic (ARED) flow in the UA at 24-34 weeks of gestation, which were delivered before 34 weeks' gestation, were examined. Absent or reversed flow during atrial contraction (a-wave) in the DV and pulsatile flow in the UV were examined to predict severe perinatal outcomes (stillbirth, neonatal death, perinatal death, acidemia, 5 min Apgar < 7, intraventricular hemorrhage and elevated nucleated red blood cell counts at delivery). RESULTS: Twelve (16.2%) perinatal deaths, of which eight were stillbirths (10.8%), and two (2.7%) neonatal deaths occurred among 74 fetuses. Logistic regression analysis confirmed that abnormal DV Doppler waveforms (R2 = 0.57, P < 0.001) together with gestational age at delivery (R2 = 0.57, P < 0.001) showed the strongest association with perinatal death, whereas only gestational age was significantly related to neonatal death (R2 = 0.67, P < 0.05). Abnormal DV Doppler waveforms (R2 = 0.86, P < 0.001) and gestational age (R2 = 0.49, P < 0.05) were strongly associated with adverse outcome (including stillbirth, perinatal death or neonatal death). Abnormal venous Doppler flow patterns performed better in the prediction of fetal or perinatal demise than did ARED flow or brain sparing. CONCLUSION: Abnormal venous Doppler waveforms in preterm IUGR fetuses with ARED flow are strongly related to adverse fetal and perinatal outcomes before 32 weeks of gestation. The possible benefit of prolonging these pregnancies can only be evaluated in a prospective randomized study.     

超声评价新生儿胼胝体发育及影响因素

目的通过颅脑超声监测胼胝体的生长率,分析新生儿胼胝体发育的影响因素,为早期评价和治疗脑发育性疾病提供依据。 方法选择2016年4月至12月就诊于兰州大学第二医院新生儿重症监护室（NICU）的97例新生儿,其中,早产儿54例（27~34周）,足月儿43例。所有新生儿于出生后0~6周每周行颅脑超声检查并测量胼胝体矢状长度,通过独立样本t检验比较早产儿、足月儿出生后0~6周胼胝体生长率。采用Spearman相关分析孕周、新生儿出生体质量与胼胝体生长率之间的关系。 结果（1）新生儿出生时胼胝体矢状长度与孕周、出生体质量成正相关（r=0.57、0.58）;（2）早产儿出生后0周、2周、3周、4周、5周、6周胼胝体长度均低于足月儿,差异均有统计学意义（t=6.22、6.51、7.81、8.87、10.25、11.64,P均<0.001）;（3）早产儿、足月儿出生后0~2周胼胝体生长率比较,差异无统计学意义（P>0.05）,出生后2~6周每周早产儿胼胝体生长率均低于足月儿,差异均有统计学意义（t=13.91、14.76、13.85、12.21,P均<0.001）。 结论新生儿胼胝体的发育与孕周、出生体质量有关;颅脑超声能实时动态监测胼胝体的生长发育。     

Timing for the Introduction of Cycled Light for Extremely Preterm Infants: A Randomized Controlled Trial

Day‐night cycled light improves health outcomes in preterm infants, yet the best time to institute cycled light is unclear. The hypothesis of this study was that extremely preterm infants receiving early cycled light would have better health and developmental outcomes than infants receiving late cycled light. Infants born at ≤28 weeks gestation were randomly assigned to early cycled light (ECL) starting at 28 weeks postmenstrual age [PMA] or late cycled light (LCL), starting at 36 weeks PMA. Daylight was 200–600 lux and night was 5–30 lux. Primary outcomes were weight over time and length of hospitalization. Secondary outcomes were hospital costs, sleep development, and neurodevelopment at 9, 18, and 24 months corrected age. Of 121 infants randomized, 118 were included in analysis. Weight gain in the two groups did not differ significantly but increased across time in both groups. In PMA weeks 36–44, the mean weight gain was 193.8 grams in the ECL group compared to 176.3 grams in the LCL group. Effect sizes for weight were Cohen d = 0.26 and 0.36 for 36 and 44 weeks PMA. Infants in the ECL group went home an average of 5.5 days earlier than the LCL group, but this difference was not statistically significant. There were no group differences on neurodevelopmental outcomes. Although statistically non‐significant, clinically important differences of improved weight gain and decreased hospital stay were observed with ECL. The small observed effect sizes on weight during hospitalization should be considered in future cycled light research with extremely preterm infants. © 2017 Wiley Periodicals, Inc.     

S100B protein levels in saliva: correlation with gestational age in normal term and preterm newborns

OBJECTIVES: S100B is an acidic calcium-binding protein of the EF-hand family present in the central nervous system, where it is concentrated in glial cells. It has been suggested to act as a cytokine with neurotrophic effects at physiological concentrations. DESIGN AND METHODS: S100B concentration was assessed in saliva by western blot analysis and an immunoluminometric assay. A reference curve of the protein was established in 216 preterm and term newborns. RESULTS: S100B levels were significantly higher in saliva taken from the preterm group, and the highest S100B levels were found in newborns who were delivered in the earlier weeks of gestation, exhibiting a progressive decrease nearer to term. S100B concentration in saliva was correlated with gestational age (r = -0.69; P < 0.001). CONCLUSIONS: The present study offers data consistent with the putative neurotrophic role of S100B and suggests the usefulness of saliva in the clinical monitoring of S100B levels.