Effects of perinatal testosterone on infant health, mother-infant interactions, and infant development

Verbal/social autopsy analysis of causes and determinants of under-5 mortality in Tanzania from 2010 to 2016

Background

Tanzania has decreased its child mortality rate by more than 70 percent in the last three decades and is striving to develop a nationally-representative sample registration system with verbal autopsy to help focus health policies and programs toward further reduction. As an interim measure, a verbal and social autopsy study was conducted to provide vital information on the causes and social determinants of neonatal and child deaths.

Methods

Causes of neonatal and 1-59 month-old deaths identified by the 2015-16 Tanzania Demographic and Health Survey were assessed using the expert algorithm verbal autopsy method. The social autopsy examined prevalence of key household, community and health system indicators of preventive and curative care provided along the continuum of care and Pathway to Survival models. Careseeking for neonates and 1-59 month-olds was compared, and tests of associations of age and cause of death to careseeking indicators and place of death were conducted.

Results

The most common causes of death of 228 neonates and 351 1-59 month-olds, respectively, were severe infection, intrapartum related events and preterm delivery, and pneumonia, diarrhea and malaria. Coverage of early initiation of breastfeeding (24%), hygienic cord care (29%), and full immunization of 12-59 month-olds (33%) was problematic. Most (88.8%) neonates died in the first week, including 44.3% in their birth facility before leaving. Formal care was sought for just 41.9% of newborns whose illness started at home and was delayed by 5.3 days for 1-59 month-olds who sought informal care. Care was less likely to be sought for the youngest neonates and infants and severely ill children. Although 70.3% of 233 under-5 year-olds were moderately or severely ill on discharge from their first provider, only 29.0%-31.2% were referred.

Conclusions

The study highlights needed actions to complete Tanzania’s child survival agenda. Low levels of some preventive interventions need to be addressed. The high rate of facility births and neonatal deaths requires strengthening of institutionally-based interventions targeting maternal labor and delivery complications and neonatal causes of death. Scale-up of Integrated Community Case Management should be considered to strengthen careseeking for the youngest newborns, infants and severely ill children and referral practices at first level facilities.

Development of Polydiacetylene-Based Testosterone Detection as a Model Sensing Platform for Water-Insoluble Hormone Analytes

We have developed a polydiacetylene (PDA)-based sensing platform to detect testosterone (T) as a potential biomarker of preterm birth. The insolubility of the steroid hormone in water, where PDA assemblies are dispersed, poses a major issue, since they can hardly interact with each other. To overcome this challenge, acetonitrile was used as a suitable solvent. In addition, to minimize false signals of PDA assemblies caused by the solvent, a mixture of acetonitrile and distilled water was selected. To prove a concept of PDA-based sensing platform for targeting T hormone, we conjugated anti-T antibodies to surface of PDA assemblies to induce selective binding between T and anti-T antibodies. The fluorescence sensory signaling of the PDA-anti-T antibody conjugate was selectively generated for T, over 3.4 times higher sensitivity of the signaling compared to that from other sex steroid hormones studied (β-estradiol and progesterone).

Sex-dependent associations of maternal androgen levels with offspring BMI and weight trajectory from birth to early childhood

CONTEXT

In preclinical studies, high androgen levels during pregnancy are associated with low birth weight and rapid postnatal weight gain in the offspring. However, human data linking prenatal androgens with birth weight and early life weight gain in the offspring are scarce.

DESIGN

We evaluated 516 mother-child pairs enrolled in the New England birth cohorts of the Collaborative Perinatal Project (1959-1966). We assayed androgen bioactivity in maternal sera during third-trimester using a receptor-mediated luciferase expression bioassay. Age and sex-specific BMI Z-scores (BMIz), defined using established standards, were assessed at birth, 4 months, 1 year, 4 years, and 7 years. We used linear mixed models to evaluate the relation of maternal androgens with childhood BMIz overall and by sex. We examined the association of maternal androgens with fetal growth restriction. The association of weight trajectories with maternal androgens was examined using multinomial logistic regression.

RESULTS

Higher maternal androgen levels associated with lower BMIz at birth (β = - 0.39, 95% CI: - 0.73, - 0.06); this relation was sex-dependent, such that maternal androgens significantly associated with BMIz at birth in girls alone (β = - 0.72, 95% CI: - 1.40, - 0.04). The relation of maternal androgens with fetal growth restriction revealed dose threshold effects that differed by sex. There was no significant association between maternal androgens and weight trajectory overall. However, we found a significant sex interaction (p = 0.01); higher maternal androgen levels associated with accelerated catch-up growth in boys (aOR = 2.14, 95% CI: 1.14, 4.03).

CONCLUSION

Our findings provide evidence that maternal androgens may have differential effects on the programming of intrauterine growth and postnatal weight gain depending on fetal sex.

Neurobiological changes during the peripartum period: implications for health and behavior

Pregnancy and the transition to parenthood is an important period marked by dramatic neurobiological and psychosocial changes that may have implications for the health of women and offspring. Although human and non-human animal research suggests that the brain undergoes alterations during the peripartum period, these changes are poorly understood. Here, we review existing research, particularly human neuroimaging and psychophysiological research, to examine changes in brain structure and function during the peripartum period and discuss potential implications for the health of women and offspring. First, we discuss the potential causes of these changes across pregnancy, including physiological and psychosocial factors. Next, we discuss the evidence for structural and functional changes in the brain during pregnancy and into the postpartum period, noting the need for research conducted prospectively across human pregnancy. Finally, we propose potential models of individual differences in peripartum neurobiological changes (i.e. hypo-response, typical response, hyper-response) and emphasize the need to consider trajectories of change in addition to pre-existing factors that may predict maternal adjustment to parenthood. We suggest that the consideration of individual differences in neurobiological trajectories across pregnancy may contribute to a better understanding of risk for negative health and behavior outcomes for women and offspring.

Associations Between Hormonal Biomarkers and Cognitive, Motor, and Language Developmental Status in Very Low Birth Weight Infants

BACKGROUND

Male infants are more prone to health problems and developmental delays than female infants.

OBJECTIVES

On the basis of theories of gender differences in brain development and social relationships, we explored associations between testosterone and cortisol levels with infant cognitive, motor, and language development ("infant development") in very low birth weight (VLBW) infants, controlling for mother-infant interactions, characteristics of mothers and infants, and days of saliva collection after birth.

METHODS

A total of 62 mother-VLBW infant pairs were recruited from the newborn intensive care unit of a tertiary medical center in the Southeast United States. Data were collected through infant medical record review, biochemical measurement, observation of mother-infant interactions, and standard questionnaires. Infant development was assessed at 6 months corrected age (CA), and mother-infant interactions were observed at 3 and 6 months CA.

RESULTS

General linear regression with separate analyses for each infant gender showed that high testosterone levels were positively associated with language development of male infants after controlling for mother-infant interactions and other covariates, whereas high cortisol levels were negatively associated with motor development of female infants after controlling for mother-infant interactions.

CONCLUSIONS

Steroid hormonal levels may well be more fundamental factors for assessing infant development than infant gender or mother-infant interactions at 6 months CA.

Gender Differences in Infant Mortality and Neonatal Morbidity in Mixed-Gender Twins

In the present study, we aimed to explore gender differences in infant mortality and neonatal morbidity in mixed-gender twin pairs. Data were obtained from the US National Center for Health Statistics Linked Birth-Infant Death Cohort. A total of 108,038 pairs of mixed-gender twins were included in this analysis. Among the mixed-gender twins, no significant difference in the odds of fetal mortality between male twins (1.05%) and female co-twins (1.04%). However, male twins were at increased odds of neonatal mortality (adjusted OR 1.59; 95% CI 1.37, 1.85) and overall infant mortality (adjusted OR 1.43; 95% CI 1.27, 1.61) relative to their female co-twins. Congenital abnormalities (adjusted OR 1.38; 95% CI 1.27, 1.50) were identified significantly more frequently in male than female twins. Moreover, increased odds of having low 5-minute Apgar score (<7) (adjusted OR 1.15; 95% CI 1.05, 1.26), assistant ventilation >30 minutes (adjusted OR 1.31; 95% CI 1.17, 1.47), and respiratory distress syndrome (adjusted OR 1.45; 95% CI 1.26, 1.66) were identified in male twins relative to their female counterparts. The results of our study indicated that in mixed-gender twin pairs, the odds of infant mortality and neonatal morbidity were higher in male twins than their female co-twins.

Gross Motor Trajectories During the First Year of Life for Preterm Infants With Very Low Birth Weight

BACKGROUND

Early identification of motor dysfunction in preterm infants with very low birth weight (VLBW) is important in order to provide early intervention.

OBJECTIVE

This study was to examine the motor trajectories of preterm infants with VLBW during their first year of life and to investigate the predictive ability and influencing factors of the trajectories.

DESIGN AND METHODS

A total of 342 preterm infants with VLBW were prospectively assessed for motor development by the Alberta Infant Motor Scales at 4, 6, 9, and 12 months and for developmental outcomes using the Bayley Scales of Infant and Toddler Development, second edition, at 24 months. Perinatal and socio-environmental factors were collected at baseline. Growth mixture modeling was used to explore the patterns of infants' motor trajectories during their first year of life. Logistic regression analyses were applied to examine the influencing factors associated with motor trajectories and their predictability of 24-month developmental outcomes.

RESULTS

Preterm infants with VLBW showed 3 distinct motor trajectories: stably normal (55%), deteriorating (32%), and persistently delayed (13%). Furthermore, the motor trajectories were predictive of 24-month cognitive and motor outcomes. Perinatal factors including lower birth weight, male gender, moderate to severe bronchopulmonary dysplasia, stage III to IV retinopathy of prematurity, and major brain damage were associated with a risk of deteriorating and persistently delayed trajectories (all P < .05). Socio-environmental factors had no association with motor trajectories.

LIMITATIONS

The small sample size of the infants with a persistently delayed trajectory may have limited the assessment of some influencing factors.

CONCLUSION

The identified early motor trajectories, predictive values, and influencing factors provide insightful implications for early detection and prevention of motor -disorders in preterm infants with VLBW.