Influence of clinical status on the association between plasma total and unbound bilirubin and death or adverse neurodevelopmental outcomes in extremely low birth weight infants.

OBJECTIVES: To assess the influence of clinical status on the association between total plasma bilirubin and unbound bilirubin on death or adverse neurodevelopmental outcomes at 18-22 months corrected age in extremely low birth weight infants. METHOD: Total plasma bilirubin and unbound bilirubin were measured in 1101 extremely low birth weight infants at 5 +/- 1 days of age. Clinical criteria were used to classify infants as clinically stable or unstable. Survivors were examined at 18-22 months corrected age by certified examiners. Outcome variables were death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death prior to follow-up. For all outcomes, the interaction between bilirubin variables and clinical status was assessed in logistic regression analyses adjusted for multiple risk factors. RESULTS: Regardless of clinical status, an increasing level of unbound bilirubin was associated with higher rates of death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss and death before follow-up. Total plasma bilirubin values were directly associated with death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death before follow-up in unstable infants, but not in stable infants. An inverse association between total plasma bilirubin and death or cerebral palsy was found in stable infants. CONCLUSIONS: In extremely low birth weight infants, clinical status at 5 days of age affects the association between total plasma bilirubin and death or adverse neurodevelopmental outcomes at 18-22 months of corrected age. An increasing level of UB is associated a higher risk of death or adverse neurodevelopmental outcomes regardless of clinical status. Increasing levels of total plasma bilirubin are directly associated with increasing risk of death or adverse neurodevelopmental outcomes in unstable, but not in stable infants.

Human lactational and ovarian response to endogenous prolactin release.

Radioimmunoassayable prolactin rises in postpartum women during nursing and after intravenous thyrotropin-releasing hormone (TRH). Prolactin release induced by TRH can be dissociated from the postsuckling response. In addition to this, increases in endogenous prolactin secretion are followed by marked breast engorgement and milk letdown, especially after intravenous TRH. In this group of breast-feeding women, vaginal smears remained atrophic even up to 410 postpartum days. Prolactin appears to influence the production of breast milk, and the maintenance of a regular nursing pattern seems to promote the maintenance of ovarian unresponsiveness to circulating gonadotropins.

Functional evaluation of prolactin secretion: a guide to therapy.

Stimulation and inhibition tests are proposed for evaluating prolactin secretion. Thyrotropin-releasing hormone (TRH) stimulates the release of prolactin from the pituitary. Chlorpromazine acts presumably at the hypothalamic level to increase prolactin secretion. L-Dopa (D,L-alpha-hydrazino-alpha-methyl-beta-[3,4-di-hydroxyphenyl]) has the opposite effect; it inhibits prolactin secretion and may be effective in suppressing galactorrhea.

Teaching teamwork during the Neonatal Resuscitation Program: a randomized trial.

OBJECTIVE: To add a team training and human error curriculum to the Neonatal Resuscitation Program (NRP) and measure its effect on teamwork. We hypothesized that teams that received the new course would exhibit more teamwork behaviors than those in the standard NRP course. STUDY DESIGN: Interns were randomized to receive NRP with team training or standard NRP, then video recorded when they performed simulated resuscitations at the end of the day-long course. Outcomes were assessed by observers blinded to study arm allocation and included the frequency or duration of six team behaviors: inquiry, information sharing, assertion, evaluation of plans, workload management and vigilance. RESULT: The interns in the NRP with team training group exhibited more frequent team behaviors (number of episodes per minute (95% CI)) than interns in the control group: information sharing 1.06 (0.24, 1.17) vs 0.13 (0.00, 0.43); inquiry 0.35 (0.11, 0.42) vs 0.09 (0.00, 0.10); assertion 1.80 (1.21, 2.25) vs 0.64 (0.26, 0.91); and any team behavior 3.34 (2.26, 4.11) vs 1.03 (0.48, 1.30) (P-values <0.008 for all comparisons). Vigilance and workload management were practiced throughout the entire simulated code by nearly all the teams in the NRP with team training group (100% for vigilance and 88% for workload management) vs only 53 and 20% of the teams in the standard NRP. No difference was detected in the frequency of evaluation of plans. CONCLUSION: Compared with the standard NRP, NRP with a teamwork and human error curriculum led interns to exhibit more team behaviors during simulated resuscitations.

A free parking trial to increase visitation and improve extremely low birth weight infant outcomes.

OBJECTIVE: Frequent parental visits are likely to benefit infants in a neonatal intensive care unit (NICU), particularly extremely low birth weight (ELBW; ⩽1000 g) survivors. Parking costs (⩾$10 per visit in our center) may deter visitation, especially for low-income parents. We assessed whether free parking (FP) decreased survivors' length of stay (LOS). STUDY DESIGN: Parents (N=138) of ELBW infants (7 to 14 days old) were randomized to usual care (UC; n=66) or FP (n=72). The primary outcome was LOS. RESULTS: Among survivors (n=116), LOS was not significantly less with FP than UC (means: FP=89, UC=102 days, P=0.22; medians: FP=82, UC=84 days, P=0.30). Groups did not differ significantly on proportion of visit days (FP=0.69, UC=0.72, P=0.47), parental involvement, knowledge/skills and satisfaction. Post hoc analyses found that parents with a greater income, a car and fewer children visited more. CONCLUSION: More potent interventions than FP are needed to increase parental visits and reduce LOS for ELBW infants in disadvantaged urban populations.

Hypoglycemia in man pathologic and physiologic variants.

To determine if an effective method existed for distinguishing the physiologic hypoglycemia of fasting from pathologic hypoglycemia, 72-hour fasts were conducted in 60 women and 20 men of normal weight, in 16 obese subjects, and in six of 11 patient with insulinomas. Only the pattern of change of the immunoreactive-insulin-to-glucose ratio (the I/G ratio), calculated at major time intervals of the fast, provided a clear-cut distinction between these groups; plasma glucose values alone could not make this distinction. The mean fasting I/G ratio was calculated for each subject from that subject's I/G ratios at 12-hour intervals during the fasting period. In no single case did the mean I/G ratio during fasting for an individual of normal weight equal or exceed the control I/G. I/G ratios increased dramatically during fasting in each patient with an insulinomas. Normal obese patients (15% greater than ideal body weight) did not provide a diagnostic problem, since, regardless of sex, glucose values of less than 55 mg/dl. did not occur. Although the pattern of change of the I/G ratio was extremely useful, the basal I/G ratio alone was potentially misleading; this was due to overlap of basal I/G ratios between subjects with simple obesity and patients with insulinomas. In addition, absolute values for the I/G ratio varied with the technique employed for measuring glucose and insulin. Change of the I/G ratio, however, was independent of the techniques used for measuring glucose and insulin. DIABETES 26:161-65, March, 1977.

Trophic feedings for parenterally fed infants.

BACKGROUND: Because of concern that feedings may increase the risk of necrotizing enterocolitis, some high-risk infants have received prolonged periods of parenteral nutrition without enteral feedings. Providing trophic feedings (small volume feedings given at the same rate for at least 5 days) during this period of parenteral nutrition was developed as a strategy to enhance feeding tolerance and decrease time to reach full feedings. Whether trophic feedings result in better outcomes than initially withholding feedings or providing progressively increasing feedings can be established only in proper clinical trials. OBJECTIVES: 1. For high-risk neonates receiving parenteral feedings, to assess the effect of trophic feeding compared to no enteral nutrient intake on measures of feeding tolerance and neonatal outcome.2. For high-risk neonates receiving parenteral feedings to assess the effect of trophic feedings compared to a specific initial feeding regimen involving a greater enteral nutrient intake on measures of feeding tolerance and neonatal outcome. SEARCH STRATEGY: Searches were performed of MEDLINE (1966 - June 2004), CINAHL (1982 - June 2004), the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 3, 2004), abstracts and conference proceedings, references from relevant publications in the English language, and studies identified by personal communication. SELECTION CRITERIA: Only randomized or quasi-randomized clinical trials were considered. Trials were included if they enrolled high-risk infants randomly assigned to receive trophic feedings (defined as dilute or full strength feedings providing < = 25 kcal/kg/d for > = 5d) compared to either 1) no enteral nutrient intake (no feedings or water only) or 2) a specific feeding regimen involving a greater enteral intake of formula or human milk than with trophic feedings. DATA COLLECTION AND ANALYSIS: The two reviewers reached consensus for inclusion of trials. Data regarding clinical outcomes were extracted and evaluated by the two reviewers independently of each other. Authors were contacted as needed and feasible to clarify or provide missing data. The specific data that were needed were requested in writing. MAIN RESULTS: 1. Trophic feedings vs. no feedings (10 trials): Among infants given trophic feedings, there was an overall reduction in days to full feeding (weighted mean difference [WMD] = -2.6 [95% confidence limits = -4.1, -1.0]), total days that feedings were held (WMD = -3.1 [-4.6, -1.6]), and total hospital stay (WMD = -11.4 [-17.2, -5.7] compared to infants given no enteral nutrient intake. Tests for heterogeneity were significant in analyses of days to full enteral feedings, days to regain birth weight, days of phototherapy, and hospital stay. There was no significant difference in necrotizing enterocolitis, although the findings do not exclude an important effect (relative risk = 1.16 [0.75, 1.79]; risk difference = 0.02 [-0.03, 0.06].2. Trophic feedings vs. advancing feedings (one trial): Infants given trophic feedings required more days to reach full enteral feeding (13.4 [8.2, 18.6]) and tended to have a longer hospital stay (11.0 [-1.4, 23.4]) than did infants given advancing feedings. With only eight total cases of necrotizing enterocolitis, trophic feedings were associated with a marginally significant reduction in necrotizing enterocolitis (relative risk =0.14 [0.02, 1.07]; risk difference = -0.09 [-0.16, -0.01]. AUTHORS' CONCLUSIONS: In both comparisons, the group with the greater enteral intake (trophic feedings in the first comparison and advancing feedings in the second comparison) required significantly less time to reach full feedings and had a significant or near significant reduction in hospital stay. In both comparisons, the group with the greater intake also had a higher incidence of necrotizing enterocolitis although the difference was not statistically significant. The concern is greatest for the advancing feeding regimen. Even when trophic feedings were compared to no feedings, the relative risk for necrotizing enterocolitis was 1.16 (0.75 - 1.79), a finding consistent with a 16% increase in necrotizing enterocolitis and a number needed to harm of 50. A true increase of this magnitude might outweigh any short- or long-term benefits of trophic feedings. Moreover, the 95% confidence interval does not exclude the possibility that trophic feedings increase necrotizing enterocolitis by as much as 79% with a number needed to harm of 17. Whether no feedings, trophic feedings, or advancing feedings should initially be used is difficult to discern for a variety of reasons--the inherent difficulty of assessing enteral feedings in high-risk infants, the limited sample size and methodologic limitations of most studies to date, unexplained heterogeneity with respect to a number of outcomes, the potential for bias to affect the findings in unblinded studies, and the large number of infants who must be studied to assess the effect on necrotizing enterocolitis. One or more large, well designed, multi-center trials are needed to compare these approaches to early feeding with respect to important clinical outcomes. A conclusive evaluation would assess effects on not only the survival rate without necrotizing enterocolitis prior to discharge from the neonatal unit but also on the survival rate without severe gastrointestinal or neurodevelopmental disability at >= 18 months age.

Serial aEEG recordings in a cohort of extremely preterm infants: feasibility and safety.

OBJECTIVE: Amplitude-integrated electroencephalography (aEEG) monitoring is increasing in the neonatal population, but the safety and feasibility of performing aEEG in extremely preterm infants have not been systematically evaluated. STUDY DESIGN: Inborn infants 23(0/7) to 28(6/7) weeks gestation or birth weight 401 to 1000 g were eligible. Serial, 6-h aEEG recordings were obtained from first week of life until 36 weeks postmenstrual age. Adverse events were documented, and surveys evaluated the impact of the aEEGs on routine care. Success of performing aEEGs according to protocol and aEEG quality were assessed. RESULT: A total of 102 infants were enrolled, with 755 recordings performed. 83% of recordings were performed according to schedule, and 96% were without adverse event. Bedside nurses reported no interference with routine care for 89% of recordings. 92% of recordings had acceptable signal quality. CONCLUSION: Serial aEEG monitoring is safe in preterm infants, with few adverse events and general acceptance by nursing staff.

Role of the hypothalamic-pituitary-ovarian axis in puerperal infertility.

To gain further insight into the mechanisms of postpartum infertility, plasma gonadotropins, prolactin, estradiol, and progesterone were measured following either iv LHRH or im menopausal gonadotropins (Pergonal) to postpartum women. Plasma estradiol and progesterone rose significantly between 24-72 hours following hMG injection. The response was similar in both nursing and non-nursing women throughout the intermediate and late postpartum study interval. No gonadotropin response was observed following LHRH injection in the early puerperium. Beyond five postpartum weeks, a significantly greater response following LHRH was observed in nursing compared with non-nursing women. A subsequent and significant rise in estradiol correlated with the magnitude of the LHRH-induced increment. Basal prolactin levels in nursing women were significantly greater than in non-nursing women but were unchanged after either hMG or LHRH. We conclude that the postpartum ovary is not refractory to either direct exogenous gonadotropin stimulation or to endogenously released gonadotropins, at least as far as estrogen production is concerned. Furthermore, the difference in the pituitary response to LHRH in nursing and non-nursing women may reflect a difference in the hypothalamic-pituitary axis. Elevated prolactin secretion in response to nursing may be involved in postpartum infertility, but the specific role remaine unclear.

Human lactational response to oral thyrotropin releasing hormone.

Several studies were designed to evaluate the effect of oral TRH on prolactin (PRL) secretion and mammary function in nursing women. Initially, efficacy was studied in nursing women following 5 mg TRH. PRL levels rose to a mean maximum of 46.3 ng/ml above baseline at 60 min. Plasma TSH also incresed from a mean baseline of 2.6 to 17.6 muU/ml at 180 min. No changes were observed following placebo. In order to observe the long term effects of oral TRH, two groups of women in full nursing were studied. Beginning on day 29 postpartum, either 5 mg TRH or placebo were taken twice daily for four weeks. No chronic elevations were observed in maternal PRL and TSH or in infant TSH before or after one month of either regimen. Milk composition expressed in terms of per cent protein and per cent fat did not differ between the groups. Weekly gonadotropin levels were also similar as were infant weight gain and growth. In a group of women with lactational insufficiency receiving 5-20 mg TRH twice daily for five days, basal PRL concentrations markedly increased. While changes in milk composition were not significant, fat percentages increased slightly and protein percentages declined. Breast engorgement and milk letdown increased and full nursing was restored. While the oral TRH used in fully nursing women had no demonstrable effect on mammary function, it may prove useful in those women with lactational insufficiency. Because two women developed iatrogenic hyperthyroidism following 40 mg oral TRH twice daily, care must be exercised in determining the dosage to be employed.

Insulin-like growth factors in amniotic fluid.

The concentrations of insulin-like growth factors I and II (IGF-I and IGF-II) in amniotic fluid were determined by specific immunoassays in 58 women. IGF-I concentrations were constant throughout gestation at approximately 20 ng/ml; the mean IGF-II concentration was 114 +/- 13 (+/- SE) ng/ml at the earliest period of gestation studied and remained unchanged at 26 to 33 weeks despite a greater than 50% decrease in amniotic fluid total protein. A precipitous decrease in IGF-II concentration occurred at term which was not explainable by alterations in total amniotic fluid protein concentration. The concentrations of IGF-I and IGF-II in amniotic fluid did not correlate with concentrations of these factors in maternal serum (r = 0.08 and 0.09, respectively). [125I]IGF-I and [125I]IGF-II, after incubation with amniotic fluid, bound to a 40-45 K protein (or proteins). A carrier protein of greater mol wt, as in serum, was not detected. These findings indicate that there is dynamic control of IGF in amniotic fluid during normal pregnancy.

The influence of prolactin secretion on human lactation.

The elevation of endogenous prolactin secretion using thyrotopin releasing hormone was associated with significant increases in mammary milk production in postpartum women. More-over, a specific effect was seen on the percent fat composition which has been shown to rise as much as 228% over pretest conditions. As in the bovine, administration of high doses of estrogen is associated with mammary breast development and the sudden removal of this stimulus if accompanied by nipple stimulation is associated with non-puerperal lactation. The inhibitory effects of estrogen on the mammary cellular response to circulating prolactin has been deduced from studies in pregnant and parturient women by measuing the TRH-induced prolactin response. These studies support a relationship between prolactin and sex steroids on the initiation and maintenance of human lactation.

PIP: The relationship between the secretion of pituitary prolactin (hPRL) and the initiation and maintenance of human lactation was investigated. HPRL secretion was stimulated by suckling and the change was especially significant beyond the 8th postpartum day when basal hPRL concentrations return to prepregnancy levels. Intravenous thyrotropin releasing hormone (TRH) further elevated hPRL and was associated with significant increases in mammary milk production in postpartum women. Milk fat concentrations were also seen to rise, as much as 228% over pretest conditions. TRH but not suckling increased plasma pituitary thyrotropin (hTSH) concentrations. Administration of estrogens led to decreased secretion of LH and FSH, indicating a potentiating effect on the hypothalamus and/or pituitary gland. Estrogens also were associated with mammary breast development; removal of this stimulus if accompanied by nipple stimulation led to nonpuerperal lactation.

Specific cells of human amnion selectively localize prolactin.

The presence of PRL in high concentration in human amniotic fluid has been related to changes in water transport across amnion but not chorion leave. The cellular composition of human amniotic epithelium has been reported to include at least two structurally distinct cell types, known as light cells and dark cells, that differ in their ability to transport large molecules. In the present study, human amnion obtained from term cesarean section was evaluated through the use of autoradiography as to its ability to localize hormones of similar and variant molecular sizes. Amniotic epithelium exposed to [125I]human PRL, [125I]human Gh, [125I]human beta-endorphin, [125I]bovine FSH, and sodium 125I alone was found to display a selectivity in its ability to localize [125I]human PRL only. Furthermore, the selective localization of [125I]human PRL was found to be specific to the light cells, because dark cells failed to localize any of the other tracers used. These data provide additional evidence in support of the recently proposed concept that term human amniotic epithelium consists of at least two functionally distinct cell types. Furthermore, the high levels of PRL in amniotic fluid may have a specific physiologic role in the amniotic membrane during human gestation.

Quantitative comparison between biological and immunological activities of prolactin derived from human fetal and maternal sources.

The biological (BA) and immunological (IA) activities of human PRL have been determined in samples of decidual incubation medium, amniotic fluid, and maternal and fetal cord sera obtained from cesarean sections performed at term. PRL from each of the four compartments was assayed using the Nb2 node rat lymphoma cell line and homologous RIA. BA to IA ratios of PRL, when compared within and between compartments, indicate that the BA of PRL from each compartment is equivalent to that of its IA. Thus, the BA of PRL from decidual incubation medium and amniotic fluid was found not to differ from that of pituitary PRL. These data suggest that PRL produced by decidua and found in amniotic fluid is a biologically active hormone.

Adrenocortical function in hyperprolactinemic women.

To study the effects of prolactin (PRL) on adrenocortical function in humans, dehydroepiandrosterone (DHA), dehydroepiandrosterone sulfate (DHAS), androstenedione (delta) and testosterone (T) were measured in serum obtained from 35 hyperprolactinemic women with galactorrhea and amenorrhea before and after treatment with bromocriptine-induced fall in mean PRL levels from 82 +/- 8 (SE) to 14 +/- 2 ng/ml (n = 39, P less than 0.0005), DHAS fell from 322 +/- 21 to 237 +/- 21 microgram/dl (n = 39); P less than 0.0005), DHA fell from 492 +/- 47 to 378 +/- 30 ng/dl (n = 39; P less than 0.01) while T (n = 16) and delta (n = 13) levels were unchanges (44 +/- 4 vs. 49 +/- 4 ng/dl and 280 +/- 55 vs. 236 +/- 40 ng/dl, respectively). In addition, 4 women were infused iv with 25 microgram synthetic ACTH over 4 h and serial blood samples drawn while hyperprolactinemic, and again 2-4 months later following normalization of PRL levels by bromocriptine. Although pre-infusion levels of DHAS were lower when PRL levels were normalized, no significant differences in responses of circulating DHAS, DHA, T, cortisol and 17-hydroxyprogesterone concentrations were detected between the two infusions. Since DHAS is virtually an exclusive product of the adrenal cortex, and since high PRL levels appear to inhibit ovarian steroid production, the findings suggest that hyperprolactinemia selectively stimulates adrenocortical androgen production.

The small for gestational age infant: accelerated or delayed pulmonary maturation? Increased or decreased survival?

OBJECTIVE: Small for gestational age (SGA) neonates have been considered to have accelerated pulmonary maturation and thus a lower risk for respiratory distress syndrome (RDS) than appropriate for gestational age (AGA) neonates. This, however, has not been thoroughly examined. Therefore, we compared SGA infants with AGA infants of the same gestational age (GA) with respect to risk of RDS, respiratory failure, or death. POPULATION: An indigent population born in a large county hospital. METHODS: Multivariate analyses were performed controlling for GA alone or for GA, race, sex, and congenital anomalies. Because the proper method to identify SGA infants is unclear, we performed separate analyses using different GA estimates (obstetric or pediatric) and intrauterine growth grids (hospital-specific grids or grids for a healthy, geographically-defined population). RESULTS: SGA infants did not fare better than AGA infants in any analysis. SGA infants had significantly increased risk in some analyses of RDS and in almost all analyses of respiratory failure or death. The risk associated with being SGA was generally comparable to that associated with male sex or White race. CONCLUSION: The concept that intrauterine growth retardation accelerates lung maturation and improves outcome is not supported in comparisons of SGA and AGA infants of the same GA, sex, and race. This widely accepted concept deserves critical re-evaluation.

Aid to the evaluation of therapeutic studies.

Physicians are often faced with conflicting recommendations from therapeutic studies. An evaluation form is proposed to facilitate the evaluation of the quality of therapeutic studies and the resulting treatment or management recommendations in any area of medicine. Twelve major topics for evaluation include sample size determination, randomization, selection of control group(s), "blinding," and support for treatment recommendations. Emphasis is placed on study design and performance rather than data analysis. Thirty-four primary criteria based on accepted research standards are designated as most important, and examples from the literature are provided to illustrate their use. The form provides a comprehensive set of well-accepted standards of research in a format that encourages detailed, consistent, and thoughtful evaluation of therapeutic studies. The evaluation form is recommended as a tool for physicians who wish to develop and exercise skill in evaluating therapeutic studies.

Very low birth weight outcomes of the National Institute of Child Health and Human Development Neonatal Network.

This report describes the neonatal outcomes of 1765 very low birth weight (less than 1500 g) infants delivered from November 1987 through October 1988 at the seven participating centers of the National Institute of Child Health and Human Development Neonatal Intensive Care Network. Survival was 34% at less than 751 g birth weight (range between centers 20% to 55%), 66% at 751 through 1000 g (range 42% to 75%), 87% at 1001 through 1250 g (range 84% to 91%), and 93% at 1251 through 1500 g (range 89% to 98%). By obstetric measures of gestation, survival was 23% at 23 weeks (range 0% to 33%), 34% at 24 weeks (range 10% to 57%), and 54% at 25 weeks (range 30% to 72%). Neonatal morbidity included respiratory distress (67%), symptomatic patent ductus arteriosus (25%), necrotizing enterocolitis (6%), septicemia (17%), meningitis (2%), urinary tract infection (4%), and intraventricular hemorrhage (45%, 18% grade III and IV). Morbidity increased with decreasing birth weight. Oxygen was administered for greater than or equal to 28 days to 79% of less than 751-g birth weight infants (range between centers 67% to 100%), 45% of 751- through 1000-g infants (range 20% to 68%), and 13% of 1001- through 1500-g infants (range 5% to 23%). Ventilator support for greater than or equal to 28 days was given to 68% of infants at less than 751 g, 29% at 751 through 1000 g, and 4% at greater than 1000 g. Hospital stay was 59 days for survivors vs 15 days for infants who died. Sixty-nine percent of survivors had subnormal (less than 10th percentile) weight at discharge. The data demonstrate important intercenter variation of current neonatal outcomes, as well as differences in philosophy of care and definition and prevalence of morbidity.

Randomized trial of taurine supplementation for infants less than or equal to 1,300-gram birth weight: effect on auditory brainstem-evoked responses.

Taurine may be important to the developing eye and brain of the small preterm infant. A blinded randomized trial was conducted to determine whether taurine supplementation of healthy infants of less than or equal to 1,300 g birth weight until their discharge from the hospital increases their growth rate, neurobehavioral development, electroretinographic development, or maturation of auditory brainstem-evoked responses. Infants were fed with Similac Special Care as desired, which was prepared to contain less than 5 mg/L of taurine or 45 mg/L of taurine, a concentration similar to that of human milk. Infants who did not receive taurine supplementation (n = 19) and those who did (n = 18) were similar with respect to condition at study entry, caloric intake, and growth rates throughout the study, and electroretinographic findings and scores on the Brazelton Behavioral Assessment Scale at 37 weeks' postmenstrual age. Infants who received taurine supplementation had greater overall plasma taurine concentrations. The group receiving taurine supplementation also had more mature auditory-evoked responses at 37 weeks' postmenstrual age with a modest (0.2 to 0.5 ms) but consistent reduction (P less than .05) in the interval between stimulus and response at two different stimulation rates. Although further study is needed, taurine intake appears to influence auditory system maturation of preterm infants.