June Cho

Effects of Maternal Depressive Symptoms and Infant Gender on the Interactions Between Mothers and Their Medically At-Risk Infants

OBJECTIVE To examine the effects of maternal depressive symptoms and infant gender on interactions between mothers and medically at-risk infants. DESIGN Longitudinal, descriptive secondary analysis. SETTING Neonatal intensive care unit, intermediate care unit, and infectious disease clinic of the tertiary medical centers in the Southeast and East. PARTICIPANTS One hundred and eight preterm infants and their mothers, 67 medically fragile infants and their mothers, and 83 infants seropositive for HIV and their primary caregivers were studied in their homes between 6 and 24 months. MAIN OUTCOME MEASURES Observation and the Home Observation for Measurement of the Environment Inventory were used to assess the interactions of mothers and their medically at-risk infants. Maternal depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale. RESULTS The level of depressive symptoms did not differ between the mothers of boys and mothers of girls in the three groups. Mothers of medically fragile infants had higher levels of depressive symptoms than mothers of preterm infants at 6 months corrected age and similar levels of depressive symptoms as HIV-positive mothers at 12 months. Mothers of medically fragile infants with elevated depressive symptoms were less attentive and more restrictive to their infants. HIV-positive mothers with elevated depressive symptoms were less attentive to their infants. The effects of gender on mother-infant interactions were not moderated by maternal depressive symptoms. CONCLUSION Maternal depressive symptoms had a somewhat negative effect on the interactions of mothers and medically at-risk infants.

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

Objective: Many researchers and health care providers have noticed male vulnerability in infant health, mother–infant interactions, and some infant cognitive development, especially among very low birth weight (VLBW) preterm infants. However, factors beyond gender that could explain these observed differences have not been clear. The purpose of this article is to review the literature on the subject and to introduce a conceptual framework relating these factors. Discussion: According to gender-difference theories, prenatal exposure to high levels of testosterone may influence infant health and mother–infant interactions by negatively affecting infant cognitive/motor/language development. We constructed a conceptual framework based on the associations among biological (perinatal testosterone), stress-related (perinatal and maternal cortisol), and developmental (infant cognitive/motor/language skills) factors. If research establishes these biological, environmental, and developmental associations in mother–VLBW preterm pairs, the results will highlight the importance of addressing gender differences in nursing research and encourage the development of nursing interventions designed to reduce stress among mothers of VLBW preterm infants, particularly male infants. Conclusion: From a psychobiosocial perspective, combining biophysiological factors such as perinatal testosterone and cortisol with socioenvironmental factors such as the quality of mother–infant interactions and infant temperament may provide a broader view of gender differences in infant health and development.

Associations of Maternal and Infant Testosterone and Cortisol Levels With Maternal Depressive Symptoms and Infant Socioemotional Problems.

This study examined the associations of testosterone and cortisol levels with maternal depressive symptoms and infant socioemotional (SE) problems that are influenced by infant gender. A total of 62 mothers and their very-low-birth weight (VLBW) infants were recruited from a neonatal intensive care unit at a tertiary medical center in the southeast United States. Data were collected at three time points (before 40 weeks’ postmenstrual age [PMA] and at 3 months and 6 months of age corrected for prematurity). Measures included infant medical record review, maternal interview, biochemical assays of salivary hormone levels in mother-VLBWinfant pairs, and standard questionnaires. Generalized estimating equations with separate analyses for boys and girls showed that maternal testosterone level was negatively associated with depressive symptoms in mothers of boys, whereas infant testosterone level was negatively associated with maternal report of infant SE problems in girls after controlling for characteristics of mothers and infants and number of days post birth of saliva collection. Not surprisingly, the SE problems were positively associated with a number of medical complications. Mothers with more depressive symptoms reported that their infants had more SE problems. Mothers with higher testosterone levels reported that girls, but not boys, had fewer SE problems. In summary, high levels of testosterone could have a protective role for maternal depressive symptoms and infant SE problems. Future research need to be directed toward clinical application of these preliminary results.

Effect of gender on the interactions between mothers and their medically at‐risk infants

This study examined effects of gender on interactions between mothers and their medically at‐risk infants: 108 premature infants, 67 medically fragile infants, and 83 infants seropositive for HIV. Systematic observation and the HOME Inventory were used to describe the mother–infant interaction. General Linear Mixed Models were used to determine whether the effect of gender was longitudinally related to the interactions between mothers and each sample of medically at‐risk infants after controlling for maternal demographics. No gender‐differentiated mother–infant interactions were found; however, premature infants and infants seropositive for HIV showed less negativism, while medically fragile infants showed more social behaviours over time. Mothers of premature and medically fragile infants were increasingly restrictive to their infants, while HIV‐positive mothers did not show this tendency. Mothers who were older, had more years of education, and married were more attentive and less restrictive to their infants than mothers who were younger, had fewer years of education, and unmarried. In addition, there were three significant interactions. Married mothers with higher education of medically fragile infants showed more attention than married mothers with lower education. Also, younger HIV‐positive mothers with fewer years of education showed the least amount of attention to their infants.

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.

Associations of Maternal Testosterone and Cortisol Levels With Health Outcomes of Mothers and Their Very-Low-Birthweight Infants:

Objective: Although the roles of testosterone and cortisol in various health problems have been extensively investigated, little is known about their associations with health outcomes in mothers and their very-low-birthweight (VLBW) infants when maternal testosterone and cortisol are examined together during the postpartum period. Method: The 101 mother–VLBW infant pairs were recruited from the neonatal intensive care unit of a tertiary medical center in the southeastern United States. Demographic information, pregnancy and labor complications of mothers, and health and growth outcomes of infants were obtained from medical records and interviews with mothers. Maternal salivary testosterone and cortisol levels were determined using enzyme immunoassay. Results: Linear regression showed that mothers who were older and had a larger body mass index experienced more pregnancy complications, whereas mothers who were single and had a cesarean section experienced more labor complications. Generalized linear models showed that mothers with high cortisol levels had more antepartum hemorrhage, whereas infants of mothers with high cortisol levels had fewer neurological insults and shorter hospitalizations than other infants. More mothers experienced premature prolonged rupture of membranes (PPROM) than chorioamnionitis, and maternal medical complications were negatively associated with infant health outcomes except PPROM, which was positively associated with infant outcomes. Conclusions: High maternal cortisol levels were associated with maternal health problems during pregnancy. Beneficial effects of PPROM and high maternal cortisol levels on infant health outcomes were important findings, and understanding the mechanisms of these relationships may be of practical value for clinicians and researchers.

Associations between maternal hormonal biomarkers and maternal mental and physical health of very low birth weight infants

The purpose of this study was to determine whether maternal mental and physical health is associated with maternal testosterone and cortisol levels, parenting of very low birth weight infants, physical exercise, and White vs non-White race. A total of 40 mothers of very low birth weight infants were recruited from a neonatal intensive care unit at a University Hospital in the Southeast United States. Data were collected through a review of medical records, standardized questionnaires, and biochemical measurement. Maternal mental and physical health status using questionnaires as well as maternal testosterone and cortisol levels using an enzyme immunoassay were measured four times (birth, 40 weeks postmenstrual age [PMA], and 6 and 12 months [age of infant, corrected age]). General linear models showed that higher testosterone levels were associated with greater depressive symptoms, stress, and poorer physical health at 40 weeks PMA, and at 6 and 12 months. High cortisol levels were associated with greater anxiety at 40 weeks PMA; however, with better mental and physical health at 40 weeks PMA, and 6 and 12 months. Physical activity was associated with lower maternal perceived stress at 12 months. Maternal health did not differ by race, except anxiety, which was higher in White than non-White mothers after birth. As very low birth weight infants grew up, maternal physical health improved but mental health deteriorated. Testosterone and cortisol levels were found to be positively correlated in women but testosterone was more predictive of maternal mental and physical health than cortisol. Indeed testosterone consistently showed its associations with maternal health. Maternal stress might be improved through regular physical exercise.