Determining the exposure of maternal medicines through breastfeeding: the UmbrelLACT study protocol-a contribution from the ConcePTION project.

INTRODUCTION: Breastfeeding is beneficial for the health of the mother and child. However, at least 50% of postpartum women need pharmacotherapy, and this number is rising due to the increasing prevalence of chronic diseases and pregnancies at a later age. Making informed decisions on medicine use while breastfeeding is often challenging, considering the extensive information gap on medicine exposure and safety during lactation. This can result in the unnecessary cessation of breastfeeding, the avoidance of pharmacotherapy or the off-label use of medicines. The UmbrelLACT study aims to collect data on human milk transfer of maternal medicines, child exposure and general health outcomes. Additionally, the predictive performance of lactation and paediatric physiologically based pharmacokinetic (PBPK) models, a promising tool to predict medicine exposure in special populations, will be evaluated. METHODS AND ANALYSIS: Each year, we expect to recruit 5-15 breastfeeding mothers using pharmacotherapy via the University Hospitals Leuven, the BELpREG project (pregnancy registry in Belgium) or external health facilities. Each request and compound will be evaluated on relevance (ie, added value to available scientific evidence) and feasibility (including access to analytical assays). Participants will be requested to complete at least one questionnaire on maternal and child's general health and collect human milk samples over 24 hours. Optionally, two maternal and one child's blood samples can be collected. The maternal medicine concentration in human milk will be determined along with the estimation of the medicine intake (eg, daily infant dose and relative infant dose) and systemic exposure of the breastfed child. The predictive performance of PBPK models will be assessed by comparing the observed concentrations in human milk and plasma to the PBPK predictions. ETHICS AND DISSEMINATION: This study has been approved by the Ethics Committee Research UZ/KU Leuven (internal study number S67204). Results will be published in peer-reviewed journals and presented at (inter)national scientific meetings. TRIAL REGISTRATION NUMBER: NCT06042803.

What is Known About Cow's Milk Protein Allergy in Preterm Infants?

Background: Cow's milk protein allergy (CMPA) is well described in term infants, as opposed to preterm infants. In preterm infants, CMPA shares many gastrointestinal symptoms with necrotizing enterocolitis (NEC). Objectives: To evaluate the presentation of CMPA in preterm infants and to investigate the different diagnostic and therapeutic options. Materials and Methods: We searched for the relevant literature using the medical databases PubMed, Web of Science, and the Cochrane Library. We performed a post hoc analysis on the 25 case reports included in this study. Results: Literature was scarce and heterogeneous. The majority of preterm infants with CMPA were exposed to bovine-based milk proteins before the development of symptoms. The most common clinical manifestations were bloody stools, vomiting, and abdominal distension. Of the 25 cases, only 7 (28%) retained human milk in their diet after diagnosis. In the larger studies, no study has human milk as primary feeding choice after diagnosis. Conclusions: Preterm infants exposed to a type of cow's milk-based formula in their first days of life have a higher risk of developing CMPA. Most of the preterm infants are no longer fed with human milk after the diagnosis of CMPA is made, which is in contrast with current nutrition guidelines in preterm infants. We strongly advocate that human milk with mothers on a cow's milk-free diet is the first choice of feed after the diagnosis of CMPA. Prospective studies are necessary to obtain more information regarding clinical presentation, diagnostic tools, and therapeutic approaches.

Case Report: Bosentan and Sildenafil Exposure in Human Milk - A Contribution From the ConcePTION Project.

Introduction: Quantitative information on disposition of maternal medicines in human milk remains a major knowledge gap. This case report presents the clinical and pharmacokinetic data of a single mother-infant pair exposed to bosentan and sildenafil for the treatment of pulmonary arterial hypertension (PAH) during lactation. Case presentation: A 43-year old mother was treated with sildenafil (20 mg, 3x/day) and bosentan (125 mg, 2x/day) for PAH. Her 21-months old infant received breastfeeding in combination with adequate complementary foods. Milk samples were collected over 24 h, at day 637 and 651 after delivery. The observed average steady-state concentrations of sildenafil (2.84 µg/L) and bosentan (49.0 µg/L) in human milk were low. The Daily Infant Dosage ingested by the nursing infant through human milk was 0.02 µg/kg/day for sildenafil and 0.29 µg/kg/day for bosentan at day 637, and 0.03 µg/kg/day and 0.60 µg/kg/day at day 651. The Relative Infant Dose calculated for an exclusively breastfed infant with an estimated milk intake of 150 ml/kg/day, was 0.06% for sildenafil and 0.24% for bosentan. General health outcome of the infant, reported by the mother, was uneventful until the sampling days. Conclusion: Low medicine concentrations were found in human milk expressed 21 months after delivery after maternal intake of 20 mg sildenafil three times daily and 125 mg bosentan twice daily. General health of the nursing infant until sampling was reported as optimal by the mother.

Outcomes of Monoamniotic Twin Pregnancies from the First Trimester Onward.

INTRODUCTION: Monochorionic monoamniotic (MCMA) twins are rare, and information is lacking on pregnancy outcomes from the first trimester onward. This study compares the pregnancy and neonatal outcomes between MCMA and monochorionic diamniotic (MCDA) twin pregnancies from the first trimester onward. We also report on the outcomes of MCMA twin pregnancies continuing after 28 weeks and on the neurodevelopmental outcomes of MCMA twins. METHODS: A retrospective single-center cohort study of MCMA and MCDA twin pregnancies followed from the first trimester with a fortnightly ultrasound scan. We excluded pregnancies with a major anomaly diagnosed on the first-trimester ultrasound scan. MCMA twin pregnancies were offered inpatient monitoring from 28 weeks onward, and an elective cesarean section was advised between 32 and 33 weeks. MCDA pregnancies were managed as inpatients only if medically indicated, and an elective birth between 36 and 37 weeks was recommended. RESULTS: We analyzed the outcomes of 52 MCMA and 671 MCDA twin pregnancies. In MCMA twins, the fetal and neonatal survival rate was 81/104 (78%) versus 1,192/1,342 (89%) in MCDA twins (p = 0.016). Double intrauterine demise (IUD) was more common in MA than in DA pairs (13% vs. 3%) (p = 0.002). No IUD occurred in the 40 MCMA pregnancies that continued after 28 weeks, but five women (13%) required an urgent cesarean section for fetal distress. Thirty-eight of 52 eligible infants (73%) underwent a neurodevelopmental assessment. Thirty-three (87%) had cognitive and motor development scores within normal limits. Four infants had mild cognitive or motor impairment, and one infant was diagnosed with spastic diplegia. CONCLUSION: MCMA twins are associated with decreased survival rates compared to MCDA due to increased rates of double IUD. After 28 weeks, about one in eight women required an urgent delivery for fetal distress. Most infants had normal neurodevelopmental outcomes.

Ventilation and respiratory outcome in extremely preterm infants: trends in the new millennium.

Ventilation and respiratory care have substantially changed over the last decades in extremely premature neonates but the impact on respiratory health remains largely unclear. To determine changes in respiratory care and disease frequency in extremely premature infants, a retrospective single-centre cohort study of extremely preterm infants was performed. All infants born alive between 24 + 0 and 27 + 6 weeks of gestation in 2000-2001 (Epoch 1), 2009-2010 (Epoch 2), and 2018-2019 (Epoch 3) were included. The primary outcome of this study was the incidence of bronchopulmonary dysplasia (BPD, diagnosed according to three different criteria) or death. Secondary outcomes included the usage of different ventilation modes, changes in pharmacotherapy, and the incidence of significant extra-pulmonary morbidities. A total of 184 neonates were included of whom 151 survived until 36 weeks of corrected GA (cGA). Oxygen or positive pressure dependence increased over time (26.1%, 41.7%, and 56.1% respectively), with higher adjusted odds in Epoch 3 for the composite outcome "BPD or death" (adjusted odds ratio: 2.55 [95%CI 1.19-5.61]). Severity-based definitions showed increasing trends in survivors only. Time spent on invasive mechanical ventilation was similar throughout the years, but the use of non-invasive ventilation significantly increased in Epoch 3 (32.0 [95%CI 25.0-37.0] vs 27.0 [95%CI 26.0-32.0] vs 53.0 [95%CI 46.0-58.0] days). Moreover, mortality-adjusted rates of severe IVH, NEC, or intestinal perforation and multiple sepsis tended to decrease.   Conclusion: In spite of significant clinical advancements and adherence to novel treatment guidelines in our neonatal intensive care unit, the incidence of BPD increased over time. What is Known: • Rates of BPD are stable or increase in population-based studies. • Extremely preterm infants are particularly susceptible to developing BPD. What is New: • Despite increased use of evidence-based corticosteroid administration and early initiation of caffeine, the incidence of BPD has not decreased over the past decade.  • Increased usage of non-invasive ventilation is associated with an increase of BPD incidence.

SARS-CoV-2 Infections and Impact of the COVID-19 Pandemic in Pregnancy and Breastfeeding: Results from an Observational Study in Primary Care in Belgium.

COVID-19 also affects pregnant and breastfeeding women. Hence, clinicians and policymakers require reliable evidence on COVID-19 epidemiology and consequences in this population. We aimed to assess the susceptibility of pregnant women to SARS-CoV-2 and women's perceived impact of the pandemic on their breastfeeding practices, medical counseling and social support. We performed a cross-sectional study using an online survey in primary care in Belgium. Pregnant and breastfeeding women and women who breastfed in the preceding four weeks were eligible to participate. The survey was distributed through social media in April 2020. In total, 6470 women participated (i.e., 2647 pregnant and 3823 breastfeeding women). Overall, 0.3% of all respondents reported to have tested positive for SARS-CoV-2, not indicating a higher susceptibility of pregnant women to contracting COVID-19. More than 90% refuted that the pandemic affected their breastfeeding practices, nor indicated that the coronavirus was responsible for breastfeeding cessation. Half of the women even considered giving longer breastmilk because of the coronavirus. In contrast, women's medical counseling and social support were negatively affected by the lockdown. Women without previous breastfeeding experience and in the early postpartum period experienced a higher burden in terms of reduced medical counseling and support. In the future, more consideration and alternative supportive measures such as tele-visits by midwives or perinatal organizations are required for these women.

The placenta in fetal thyroid hormone delivery: from normal physiology to adaptive mechanisms in complicated pregnancies.

Context: Thyroid hormones are indispensable for normal fetal development. Since the fetus depends to a large extent on maternal thyroid hormone supply through the placenta, this challenges maternal thyroid economy. Several molecular mechanisms are involved in placental thyroid hormone transport and metabolism. Chronic pregnancy complications, associated with utero-placental hypoxia, trigger the development of accelerated placental maturation in order to improve fetal-placental exchange to strengthen the offspring's chance of survival. This review provides an overview of normal maternal-fetal thyroid hormone supply and explores the presence of placental adaptive mechanisms in complicated pregnancies with chronical utero-placental hypoxia to improve the thyroid hormone supply to the fetus under pressure, to end with reflections about the long term health consequences.Evidence acquisition: This work is based on a comprehensive literature review of the PubMed and Embase database, including relevant articles from 1969 to June 2018.Conclusions: The placenta is actively involved in fetal thyroid hormone delivery through a combination of stimulatory and inhibitory mechanisms. Parallel with histological adaptations to improve transplacental fetal-maternal exchange, there are indications of placental adaptive mechanisms in thyroid hormone transport and metabolism in case of complicated pregnancies, from animal models and in-vitro experiments. Evidence from human in-vivo studies is limited due to heterogeneity in study populations, small study samples, and technical limitations. Further research is necessary to reveal the role of the placenta in pathological circumstances. The placenta might thus be considered as the infants' black box of pregnancy. Results will contribute to more insights in the concept of fetal programming, which lays the foundations of optimum health, growth, and neurodevelopment across the lifespan.

Evolution of circulating thyroid hormone levels in preterm infants during the first week of life: perinatal influences and impact on neurodevelopment.

Background For several decades, transient hypothyroxinemia of prematurity (THOP) has been a topic of debate. The pathophysiology is incompletely understood and consensus on the therapeutic approach is lacking. This study aimed at gaining a better insight into the pathogenesis by studying the trends in thyroid hormone (TH) levels during the first week of life. Methods This single-center prospective observational study analyzed the plasma levels of total thyroxine (T4) and free thyroxine (fT4), total triiodothyronine (T3), thyroid-stimulating hormone (TSH) and T4-binding globulin (TBG) in cord blood and at the end of the first week of life in 120 preterm infants (gestational age [GA] <37 weeks). The change over time was calculated (delta, ∆). The impact of perinatal and subsequently postnatal variables on ∆ was studied by hierarchical multiple regression. The impact of ∆ on the neurodevelopmental outcome at the corrected ages of 9 and 24 months, measured by the Bayley Scales of Infant Development (BSID)-II, was assessed by logistic regression. Results ∆fT4 levels were negatively affected by GA and use of dopamine, whereas only GA was associated with low ∆T3 levels. Negative ∆fT4 levels were present in 75% of the extremely low-for-gestational-age infants, whereas 23.5% had a negative ∆T3 level. There was an increased risk for an abnormal mental developmental score (<85) with decreasing ∆T3 at 9 months, corrected age, but not at 24 months. Conclusions A negative evolution in circulating TH levels is principally an immaturity phenomenon, whereas dopamine can further suppress the hypothalamic-pituitary-thyroid axis. There is at least a temporary negative effect of this evolution on the infants' neurodevelopment.

Maternal and placental responses before preterm birth: adaptations to increase fetal thyroid hormone availability?

BACKGROUND: During pregnancy, maternal thyroid hormone supply is crucial for fetal development. Preterm infants often present with hypothyroxinemia. Preterm birth, either spontaneous or medically indicated, is always the result of a complicated pregnancy. We hypothesized that in preterm birth, the maternal transplacental thyroid hormone supply is influenced by the pregnancy complication and we questioned whether maternal and placental compensatory mechanisms are activated to increase thyroid hormone transfer. METHODS: Observational case-control study in mother-infant-dyads with complicated pregnancies ending in spontaneous preterm birth (n = 31) or indicated preterm birth due to vascular complications (n = 45) and normal pregnancies (healthy term controls; n = 41). At delivery, maternal and cord blood and placenta samples were collected. Cord and maternal plasma concentrations of thyroid stimulating hormone (TSH), total T4, fT4/FTI, total T3, and T4 binding globulin (TBG), and maternal serum concentrations of thyroid peroxidase (TPO)-antibodies were measured. Placental maturity was evaluated histologically and mRNA and/or protein levels of thyroid hormone deiodinases (DiO) 1, 2 and 3, and transporters (MCT8, MCT10, and OATP1c1) were quantified. RESULTS: In indicated and spontaneous preterm births, cord plasma T4 concentrations were lower than in healthy term controls (p ≤ .001), whereas T3 was only decreased in spontaneous preterm birth (p ≤ .001). Compared with spontaneous preterm births and healthy term controls, indicated preterm birth was characterized by higher maternal plasma TSH (p ≤ .05), earlier placental maturation, higher placental DiO2 gene and MCT10 protein levels and lower DiO3 gene levels (all p ≤ .01). CONCLUSIONS: Low T4 was observed in preterm infants irrespective of the cause of preterm birth, while maternal (TSH) and placental (DiO2, DiO3, and MCT10) compensatory responses were only activated in indicated preterm birth due to vascular complications. This may have mediated the normal fetal T3 availability in preterm infants born after indicated preterm birth but not after spontaneous preterm birth.

Review shows that thyroid hormone substitution could benefit transient hypothyroxinaemia of prematurity but treatment strategies need to be clarified.

AIM: Thyroid hormones are crucial for foetal and neonatal brain development. This paper provides an overview of the normal role of thyroid hormones in foetal brain development and the pathophysiology of transient hypothyroxinaemia of prematurity (THOP). It also discusses the diagnostic and therapeutic controversies around THOP and looks at directions for future research. METHODS: We used the PubMed and Embase databases to identify papers published in English from 1969 to June 2018. This identified 20 papers about the impact of THOP on neurodevelopment and seven randomised controlled trials about therapeutic approaches from 1981-2016. RESULTS: THOP has been researched for more than three decades. The impact of temporarily low thyroxine levels, without any increase in pituitary-secreted thyroid-stimulating hormone at a critical timeframe in an infant's brain development, is still debated. Heterogeneity in THOP definitions, difficulties with thyroid hormone assessment, identifying patients at risk and a clear lack of sufficiently powered studies add to the current controversy. There are indications that thyroid hormone substitution might be useful in extremely low gestational age neonates with THOP. CONCLUSION: Some preterm infants could benefit from THOP treatment, but more studies are needed to clarify further treatment strategies, including the optimal timing of initiation and duration.

Pasteurization of mother's own milk for preterm infants does not reduce the incidence of late-onset sepsis.

BACKGROUND: Feeding preterm infants human milk has a beneficial effect on the risk of late-onset sepsis (LOS). Due to lack of microbiological standards, practices such as pasteurization of mother's own milk differ widely among neonatal intensive care units worldwide. OBJECTIVES: To investigate whether pasteurization of mother's own milk for very-low-birth-weight (VLBW) infants influences the incidence and severity of infection-related outcomes. METHODS: In this randomized controlled trial, preterm infants (gestational age <32 weeks and/or birth weight <1,500 g) received either raw or pasteurized mother's own milk during the first 8 weeks of life. The primary outcome was the incidence of proven LOS. A dose-response relation was verified, i.e. the dependence of the risk of sepsis on the actual and cumulative quantities of mother's own milk. RESULTS: This study included 303 VLBW infants (mean birth weight: 1,276 g; mean gestational age: 29 weeks) whose baseline and nutritional characteristics were similar. The incidence of laboratory-confirmed sepsis was not statistically different in infants fed raw milk compared to infants who received pasteurized milk: 22/151 (0.15, CI: 0.08-0.20) and 31/152 (0.20, CI: 0.14-0.27), respectively (RR: 0.71; 95% CI: 0.43-1.17). A significant dose-response relation was observed between the adjusted quantity of enteral feeding and the risk of LOS, regardless of the type of feeding. CONCLUSION: For preterm infants, pasteurization of mother's own milk shows a trend towards an increase in infectious morbidity, although no statistical significance was reached. Practices should focus on collection, storage and labeling procedures to ensure the safety and quality of expressed milk.

Contribution of nutritional deficit to the pathogenesis of the nonthyroidal illness syndrome in critical illness: a rabbit model study.

Both starvation and critical illness are hallmarked by changes in circulating thyroid hormone parameters with typically low T(3) concentrations in the absence of elevated TSH. This constellation is labeled nonthyroidal illness (NTI). Because critical illness is often accompanied by anorexia and a failing gastrointestinal tract, the NTI of critical illness may be confounded by nutrient deficiency. In an experimental study performed in a rabbit model, we investigated the impact of nutritional deficit on the NTI of sustained critical illness. Critically ill rabbits were randomly allocated to parenteral nutrition (moderate dose 270 kcal/d) initiated on the day after injury and continued until d 7 of illness or to infusing a similar volume of dextrose 1.4% (14 kcal/d). With early parenteral nutrition during illness, the decrease in serum T(3) observed with fasting was reversed, whereas the fall in T(4) was not significantly affected. The rise in T(3) with parenteral nutrition paralleled an increase of liver and kidney type-1 and a decrease of liver and kidney type-3 deiodinase activity and an increase in circulating and central leptin. Nuclear staining of constitutive androstane receptor and its downstream expression of sulfotransferases were reduced in fasting ill animals. TRH expression in the hypothalamus was not different in fasted and fed ill rabbits, although circulating TSH levels were higher with feeding. In conclusion, in this rabbit model of sustained critical illness, reduced circulating T(3), but not T(4), levels could be prevented by parenteral nutrition, which may be mediated by leptin and its actions on tissue deiodinase activity.

Chronic renal failure: an unexpected presentation.

Chronic renal failure in childhood is mostly caused by a congenital disorder or an acquired form of glomerulonephritis. We describe a case of a 13-year-old boy from Africa who presented with a cerebrovascular accident, malignant hypertension and renal insufficiency. Aetiological workup of his hypertension revealed underlying chronic renal failure due to histologically confirmed haemolytic uraemic syndrome. This case serves to remind clinicians of the serious complications of undiagnosed chronic renal failure in a child.