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PubMed1989

Factors affecting calving interval in Italian Holstein-Friesian heifers.

Effect of rump conformation on calving interval of 520 Italian Holstein Friesian heifers was evaluated with simultaneous adjustment for herd, year of birth, calving month, age at first parturition, and milk production. All factors, except age at first parturition, were important sources of variation. Heifers with narrow rumps at the pins had the longest calving interval. There were significant differences among the herds. Cows born between 1979 and 1981 had shorter calving intervals, probably resulting from a national plan against bovine infertility initiated in 1981. Cows calving in July had better reproductive performance. There was positive relationship between milk production and calving interval.

Age Factors↗
PubMed2006

The association between low level exposures to ambient air pollution and term low birth weight: a retrospective cohort study.

BACKGROUND: Studies in areas with relatively high levels of air pollution have found some positive associations between exposures to ambient levels of air pollution and several birth outcomes including low birth weight (LBW). The purpose of this study was to examine the association between LBW among term infants and ambient air pollution, by trimester of exposure, in a region of lower level exposures. METHODS: The relationship between LBW and ambient levels of particulate matter up to 10 um in diameter (PM10), sulfur dioxide (SO2) and ground-level ozone (O3) was evaluated using the Nova Scotia Atlee Perinatal Database and ambient air monitoring data from the Environment Canada National Air Pollution Surveillance Network and the Nova Scotia Department of Environment. The cohort consisted of live singleton births (> or =37 weeks of gestation) between January 1, 1988 and December 31, 2000. Maternal exposures to air pollution were assigned to women living within 25 km of a monitoring station at the time of birth. Air pollution was evaluated as a continuous and categorical variable (using quartile exposures) for each trimester and relative risks were estimated from logistic regression, adjusted for confounding variables. RESULTS: There were 74,284 women with a term, singleton birth during the study period and with exposure data. In the analyses unadjusted for year of birth, first trimester exposures in the highest quartile for SO2 and PM10 suggested an increased risk of delivering a LBW infant (relative risk = 1.36, 95% confidence interval = 1.04 to 1.78 for SO2 exposure and relative risk = 1.33, 95% confidence interval = 1.02 to 1.74 for PM10). After adjustment for birth year, the relative risks were attenuated somewhat and not statistically significant. A dose-response relationship for SO2 was noted with increasing levels of exposure. No statistically significant effects were noted for ozone. CONCLUSION: Our results suggest that exposure during the first trimester to relatively low levels of some air pollutants may be associated with a reduction in birth weight in term-born infants. These findings have implications for the development of effective risk management strategies to minimize the public health impacts for pregnant women.

Adult↗
PubMed2002

Birth order, gestational age, and risk of delivery related perinatal death in twins: retrospective cohort study.

OBJECTIVE: To determine whether twins born second are at increased risk of perinatal death because of complications during labour and delivery. DESIGN: Retrospective cohort study. SETTING: Scotland, 1992 and 1997. PARTICIPANTS: All twin births at or after 24 weeks' gestation, excluding twin pairs in which either twin died before labour or delivery or died during or after labour and delivery because of congenital abnormality, non-immune hydrops, or twin to twin transfusion syndrome. MAIN OUTCOME MEASURE: Delivery related perinatal deaths (deaths during labour or the neonatal period). RESULTS: Overall, delivery related perinatal deaths were recorded for 23 first twins only and 23 second twins only of 1438 twin pairs born before 36 weeks (preterm) by means other than planned caesarean section (P>0.99). No deaths of first twins and nine deaths of second twins (P=0.004) were recorded among the 2436 twin pairs born at or after 36 weeks (term). Discordance between first and second twins differed significantly in preterm and term births (P=0.007). Seven of nine deaths of second twins at term were due to anoxia during the birth (2.9 (95% confidence interval 1.2 to 5.9) per 1000); five of these deaths were associated with mechanical problems with the second delivery following vaginal delivery of the first twin. No deaths were recorded among 454 second twins delivered at term by planned caesarean section. CONCLUSIONS: Second twins born at term are at higher risk than first twins of death due to complications of delivery. Previous studies may not have shown an increased risk because of inadequate categorisation of deaths, lack of statistical power, inappropriate analyses, and pooling of data about preterm births and term births.

Birth Order↗
PubMed2004

Brain-stem auditory impairment during the neonatal period in term infants after asphyxia: dynamic changes in brain-stem auditory evoked response to clicks of different rates.

OBJECTIVE: To explore dynamic changes in brain-stem auditory electrophysiology during the neonatal period in term infants after perinatal asphyxia. METHODS: Sixty-eight term newborn infants who suffered asphyxia were studied on days 1, 3, 5, 7, 14 and 30 after birth. Brain-stem auditory evoked response (BAER) was recorded with clicks, delivered at 21, 51 and 91 s(-1) and > or =40 dB above BAER threshold of each subject. RESULTS: During the neonatal period wave I latency in the infants after asphyxia increased slightly while later BAER components changed more significantly. On the first day after birth wave III and V latencies and I-V and III-V intervals increased significantly at all rates of clicks (ANOVA P<0.01-0.001). On day 3, the latencies and intervals increased further. III-V/I-III interval ratio increased at 51 and 91 s(-1), suggesting a relatively more significant increase in III-V interval than in I-III interval at higher rates. Thereafter, wave III and V latencies and all intervals decreased progressively, although these BAER variables were still significantly longer than in normal controls on days 5 and 7 (P<0.05-0.001) On day 30, all latencies and intervals approached near normal values, with a slight increase in wave V latency and I-V and III-V intervals at 51 and 91 s(-1). CONCLUSIONS: Perinatal asphyxia has a major effect on central auditory function, resulting in acute impairment. The impairment progresses during the first 3 days and then tends towards recovery. By 1 month the impaired auditory function has largely returned to normal. Significant increase in click rates can moderately improve the detection of auditory impairment. SIGNIFICANCE: After perinatal asphyxia early detection of hypoxic-ischaemic damage to the central auditory system and initialisation of neuroprotective and therapeutic measures during the first hours after birth are critical to prevent or reduce deterioration of central impairment.

Acoustic Stimulation↗
PubMed1996

Acute and chronic changes in luteinizing hormone secretion and postpartum interval to estrus in first-calf suckled beef cows exposed continuously or intermittently to mature bulls.

The objective of this study was to determine whether patterns of LH secretion are acutely or chronically affected by the presence of mature bulls in postpartum first-calf suckled beef cows exposed to bulls either continuously or intermittently beginning on d 30 after birth. Crossbred cows were assigned randomly to be either continuously exposed to (BE; n = 20) or isolated from bulls (NE; n = 32) at calving, or exposed continuously (NEBE; n = 10) or intermittently (BEI; n = 21) to bulls beginning on d 30. The BEI cows were exposed to bulls for 2 h every 3rd d for 18 d. Ten cows from the NEBE, BEI, and NE treatments only were fitted with indwelling jugular catheters. Intensive blood sampling of NEBE and BEI cows began within 45 min after they were placed with bulls for 2 h on d 30, and for BEI cows on each d after 2 h exposure. Samples were collected at 15-min intervals for 6 h beginning on d 30 for NEBE, BEI, and NE cows; sampling continued at 3-d intervals until d 48. Samples were assayed for LH by RIA. Cows were observed twice daily (am:pm) for estrus. More (P = .07) BE and NEBE (75%) cows showed estrus by the end of the study than BEI and NE cows (48%). Interval to estrus was longer (P < .05) in BEI and NE cows (95.6 +/- 6.1 d) than in BE and NEBE cows (75.9 +/- 6.1 d). Baseline LH and amplitude and interpeak interval of LH peaks during the first 6 h after 2 h of bull exposure did not differ (P > .10) among treatments on d 30 after birth. However, mean LH and LH pulse frequency were higher (P = .06) for NEBE and BEI cows than in NE cows. Baseline LH and amplitude and duration of LH peaks did not differ (P > .10) over the seven sampling periods among NEBE, BEI, or NE cows. Mean LH and LH pulse frequency were higher (P < .05) in NEBE and BEI cows than in NE cows on each sampling period. Exposing first-calf suckled beef cows to bulls on d 30 after birth increased mean LH concentrations by increasing pulse frequency within a short period after a 2-h exposure. Thereafter, mean LH concentrations were higher in cows that were either continuously or intermittently exposed to bulls. Although mean LH and LH pulse frequency in NEBE and BEI cows were similar, intervals to estrus after bull exposure differed between treatments. The mechanism whereby bulls alter postpartum interval to estrus seems to involve other factors that may be related to but not directly linked with LH secretion.

Animals↗
PubMed1992

Bladder cancer, parity, and age at first birth.

The excess of bladder cancer in males (M:F ratio of 4:1 in the United States) is not explained fully by gender differences in smoking habits or occupational exposures. Laboratory studies suggest that some androgenic hormones stimulate (or do not inhibit) oncogenesis in bladder tissue, and that estrogenic hormones have the opposite effect. These observations suggest that bladder cancer risk in females may be modified by sex hormones which undergo profound changes during and following pregnancy. Mail-questionnaire data from 317 incident female cases, and 833 population-based controls in Iowa were used to measure the effect of parity and maternal age at first birth on bladder cancer risk. Parous women were at decreased risk relative to nulliparous women (odds ratio [OR] = 0.67, 95 percent confidence interval [CI] = 0.44-1.00), after adjustment for age, tobacco use, and previous bladder infection. The overall risk reduction was restricted to women who had never smoked (OR = 0.51, CI = 0.30-0.88), with no apparent effect of parity among ever-smokers (OR = 0.93, CI = 0.49-1.77). Risk appeared to decrease with increasing age at first birth, but did not vary with increasing parity after the first birth. Our findings are consistent with the hypothesis that oncogenesis in transitional cell tissue of the human bladder is influenced by sex hormones, and that hormonal changes related to pregnancy thereby can decrease risk.

Adult↗
PubMed1989

Risk factors for breast cancer by mode of diagnosis: some results from a breast cancer screening study.

We have investigated factors affecting the probability that a woman with breast cancer participating in a mammographic screening programme will be diagnosed by the screen. Data from a large American case-control study, with subjects drawn from women participating in an annual screening programme, were used. During the screening programme, 409 cases were identified, the mode of diagnosis being screen detection for 331 and interval detection for 78. No significant relationships were found between mode of diagnosis and age, age at menarche, oral contraceptive use, age at first live birth, age at menopause or history of maternal breast cancer. There was a non-significant trend for particular mammographic patterns to be associated with interval detection. However relative risk of breast cancer and probability of interval detection were observed to increase about the time of the menopause. These results suggest that the 3 yearly mammography programme being introduced in the UK might be improved if an extra examination was included around the time of the menopause.

Breast Neoplasms↗
PubMed1998

Nutritional stress of reproduction. A cohort study over two consecutive pregnancies.

BACKGROUND: The evaluation of nutritional stresses of reproduction is far more complex than perceived in the literature so far. The use of inappropriate outcome measures, the lack of adjustment for the complex inter-relationships among confounding variables, and the poverty of analytical models, has led to conflicting results. Our objective was to evaluate, using a new analytical framework, the maternal and fetal effects of the nutritional stress imposed by reproduction in a cohort of 278 women followed over two consecutive pregnancies. METHODS: The analytical framework evaluated nutritional stress over successive pregnancies. The effect of birth interval on change in maternal weight, body mass index and hemoglobin over two consecutive pregnancies was evaluated using multiple linear regression accounting for the effects of maternal age, parity and weight or body mass index or hemoglobin in the first of the two pregnancies. For change in fetal birth weight correction was made for the confounding effect of maternal age, parity and weight, and fetal gestational age, sex and birth weight. RESULTS: Birth interval was associated with change in maternal weight (p=0.001); change in body mass index (p=0.002); and change in birth weight (p=0.048). No association was found between birth interval and change in hemoglobin. CONCLUSIONS: The nutritional stress imposed by reproduction affects maternal and fetal outcomes. Maternal nutrient stores can be depleted and fetal growth can be restricted in association with shorter birth intervals. Perinatal nutrition may be improved by adequate spacing of pregnancies with appropriate birth control.

Adult↗
PubMed1991

Changing two-year outcome of infants weighing 500 to 999 grams at birth: a hospital study.

Survival and neurodevelopmental outcome to 2 years were determined for two cohorts of infants weighing 500 to 999 gm at birth, born in a tertiary maternity hospital. Live births increased over time from an annual average of 48.7 in the first era (January 1977 to March 1982) to 64.6 in the second era (January 1985 to December 1987), largely from referrals of additional mothers with pregnancy complications. In the first era, 33.6% (86/256) of infants survived to 2 years; the survival rate improved significantly to 45.9% (89/194) in era 2. After adjustment for birth weight, the odds ratio for survival in era 2 versus era 1 was 1.39 (95% confidence interval = 1.12, 1.73; p less than 0.01). One known survivor in each era was not seen at 2 years of age. In the first era, 59.3% (51/86) of 2-year-old children were free of disability compared with 68.5% (61/89) in era 2 (NS), but the Mental Development Index of the Bayley Scales improved significantly, from 90.0 in era 1 to 98.0 in era 2. For infants weighing less than 800 gm at birth, not only did the 2-year survival rate improve, adjusted for birth weight (odds ratio = 1.53; 95% confidence interval = 1.06, 2.20; p less than 0.05), but there was also a significant reduction in neurologic disabilities in survivors (p = 0.03). For infants weighing 800 to 999 gm at birth, there was a significant improvement in the survival rate, adjusted for birth weight (odds ratio = 1.37; 95% confidence interval = 1.04, 1.79; p less than 0.05), but the rate of neurologic disabilities was unchanged. Increased survival in our tertiary maternity center was achieved without increasing the annual number of severely disabled 2-year-old survivors.

Child, Preschool↗
PubMedDate not supplied

Validating the self-reported fertility status of rural Malawian women.

This study uses data from a population-based survey to examine the fertility schedules of 704 women in a rural district of Malawi. The main objective is to assess self-reported fecundity status as a measure of fertility impairment. Life tables are used to examine the timing and tempo of births for women reporting difficulty getting pregnant as compared to women with no reported fecundity difficulties. Results of the analysis indicate that women with self-reported fecundity difficulties are older at each birth and have longer median birth intervals than do women with no reported difficulties. Cox proportional hazards models show that the report of a difficulty getting pregnant is significantly associated with at least a 30% lower likelihood of a first, second, or third birth. The relationships are not modified when accounting for demographic characteristics, previous sexual behaviors, or STI status.

Adolescent↗
PubMedDate not supplied

Longitudinal growth of Bangladeshi infants during the first year of life.

The growth in length and weight of 91 poor urban Bangladeshi infants was monitored at monthly intervals from birth to 1 year. At birth 18%, 22% and 8% were below -2.00 standard deviations of the National Center for Health Statistics (NCHS) height-for-age, weight-for-age and weight-for-height, respectively and at 1 year the percentages were 40%, 40% and 7%. Infant weights over the first 6 months associated positively with both mother's BMI and percentage body fat. Higher mean infant weights from 6 to 12 months were associated with both higher educational status of the mother and monthly family income and the latter two variables provided the best model for predicting weight velocity from birth to 12 months. Internal Z-scores, corrected for day of measurement, provided clear evidence of catch-up/catch-down over the first 6 months with heavier and longer babies at birth showing catch-down while lighter and shorter babies demonstrated catch-up. Infants' weights were almost three times more variable than lengths. Monthly incremental variability of both infant weight and length increased sharply from 6 to 12 months with weight showing significantly more variability. The correlations of birth weight and length with subsequent distances and monthly increment revealed that the first 6 months were dominated by catch-up and catch-down but during the latter half of the year the growth phenomena were influenced mainly by earlier intra-uterine or genetic effects.

Adult↗
PubMed2006

Plasminogen activator inhibitor activity, 4G5G polymorphism of the plasminogen activator inhibitor 1 gene, and first-trimester miscarriage in women with polycystic ovary syndrome.

We assessed whether hypofibrinolytic plasminogen activator inhibitor 1 (PAI-1 activity) showed an independent association with first-trimester miscarriage in the 430 women with polycystic ovary syndrome (PCOS) who had previous pregnancies (from a cohort of 967 women with PCOS). Prospectively, we hypothesized that Glucophage (Bristol-Myers Squibb, Princeton, NJ) promotes successful live births in women with PCOS by lowering PAI-1 activity before conception and maintaining further reductions of PAI-1 activity during the first trimester of pregnancy. We also assessed whether PAI-1 activity levels were independently related to PAI-1 genotype and to modifiable risk factors body mass index (BMI), insulin, and triglyceride. By stepwise logistic regression, with the dependent variable being previous pregnancy outcomes at 3 levels (live birth pregnancies only [n = 208]; both > or =1 live birth and > or =1 first-trimester miscarriage [n = 111]; or first-trimester miscarriages only [n = 71]) and explanatory variables PAI-1 genotype, PAI-1 activity, insulin, homeostasis model assessment of insulin resistance, BMI, and triglyceride, PAI-1 activity was positively associated with first-trimester miscarriage (P = .004). For each 5 IU/mL increment in PAI-1 activity, the risk being in an adverse first-trimester miscarriage category increased (odds ratio, 1.12; 95% confidence interval, 1.04-1.20). Prospectively, from pretreatment to the last preconception visit on Glucophage, in 30 women who subsequently had live births, PAI-1 activity fell 44%, but rose 19% in 23 women with first-trimester miscarriage (P = .03). In the 30 women with live birth pregnancies, median PAI-1 activity fell continuously from pretreatment through the first trimester (from 16.8 to 6.7 IU/mL), whereas PAI-1 activity was either unchanged or rose in women with first-trimester miscarriage. Of the 921 women with PCOS who had 4G5G data, 718 (78%) had 4G4G-4G5G genotypes vs 87 (69%) of 126 normal female controls (chi(2) = 4.95, P = .026). The 4G allele frequency was 53% in women with PCOS vs 46% in controls (chi(2) = 4.3, P = .04). Of the 866 women with PCOS who had PAI-1 activity data, by stepwise regression, positive independent determinants of PAI-1 activity included BMI (partial R(2) = 10.6%, P < .0001), insulin (partial R(2) = 2.8%, P < .0001), triglyceride (partial R(2) = 1.1%, P = .0009), and the 4G4G-4G5G genotype (partial R(2) = 1%, P = .0011). The PAI-1 gene 4G polymorphism is more common in women with PCOS than in normal women and, in concert with obesity, hyperinsulinemia, and hypertriglyceridemia, contributes to treatable, hypofibrinolytic, miscarriage-promoting, high PAI-1 activity. Preconception and first-trimester decrements in PAI-1 activity on Glucophage are associated with live births, whereas increments or no change in PAI-1 activity despite Glucophage appears to be associated with first-trimester miscarriage.

Abortion, Spontaneous↗
PubMed1975

Physical growth of cebus monkeys (Cebus albifrons) during the first year of life.

Infannt cebus monkeys, removed from their mothers shortly after birth, were reared in a primate nursery on diets of controlled nutritional quality. At regular intervals between birth and one year of age, each monkey was anesthetized, measured, and radiographed. Measurements were fitted to functions of the animal's age in days; a linear function for the first 6 to 8 weeks and a logarithmic function for the remainder of the first year. Mean constant curves have been calculated for each measure and estimates of animal variability have been obtained by interpolating sizes at given ages from regression lines fitted to the data for each animal. The maximum rate of growth was attained soon after birth. Cranial-caudal and distal-proximal maturity gradients in size attainment were observed.

Animal Nutritional Physiological Phenomena↗
PubMed2005

Risk of complications in a second pregnancy following caesarean section in the first pregnancy: a population-based study.

OBJECTIVE: To estimate the risks of maternal and perinatal morbidity and mortality in a second pregnancy, attributable to caesarean section in a first pregnancy. DESIGN AND SETTING: Cross-sectional analytic study of hospital births in New South Wales, based on linked population databases. PARTICIPANTS: 136 101 women with one previous birth who gave birth to a singleton infant in NSW in 1998-2002. MAIN OUTCOME MEASURES: Crude and adjusted odds ratios (aOR) and 95% confidence intervals (95% CI) for maternal and perinatal morbidity and mortality. RESULTS: 19% of mothers had a caesarean section in their first pregnancy. Compared with mothers who had had primary vaginal births, mothers who had had primary caesarean section and underwent labour in the second birth were at increased risk of uterine rupture (aOR, 12.3; 95% CI, 5.0-30.1; P < 0.0001), hysterectomy (3.5; 1.5-8.4; P < 0.01), postpartum haemorrhage (PPH) following vaginal delivery (1.6; 1.4-1.7; P < 0.0001), manual removal of placenta (1.3; 1.1-1.6; P < 0.01), infection (6.2; 4.7-8.2; P < 0.0001) and intensive care unit (ICU) admission (3.1; 2.1-4.7; P < 0.0001); among mothers who did not undergo labour (ie, had an elective caesarean section), there was a lower risk of PPH (0.6; 0.5-0.7; P < 0.0001) and ICU admission (0.4; 0.3-0.5; P < 0.0001). For infants there was increased risk of preterm delivery (1.2; 1.1-1.3; P < 0.0001) and neonatal intensive care unit admission following labour (1.6; 1.4-1.9; P < 0.0001) in the birth after primary caesarean section. The occurrence of stillbirth was not modified by labour. CONCLUSIONS: Caesarean section in a first pregnancy confers additional risks on the second pregnancy, primarily associated with labour. These should be considered at the time caesarean section in the first pregnancy is being considered, particularly for elective caesarean section for non-medical reasons.

Adult↗
PubMed2006

Previous preeclampsia, preterm delivery, and delivery of a small for gestational age infant and the risk of unexplained stillbirth in the second pregnancy: a retrospective cohort study, Scotland, 1992-2001.

Women with a previous stillbirth are known to be at increased risk of stillbirth in subsequent pregnancies. However, few studies have addressed the association between other complications of pregnancy and the future risk of stillbirth. Using linkage of national pregnancy and perinatal death registries, the authors performed a retrospective cohort study of 133,163 women having a second birth in Scotland between 1992 and 2001 whose first infant was liveborn. The risk of unexplained stillbirth was increased among women with a previous preterm birth (adjusted hazard ratio (HR) = 2.04, 95% confidence interval (CI): 1.34, 3.11), previous delivery of a small for gestational age (SGA) infant (HR = 2.14, 95% CI: 1.59, 2.87), and previous preeclampsia (HR = 1.68, 95% CI: 1.07, 2.62). The associations were similar after adjustment for maternal age, height, marital and smoking status, and interpregnancy interval. There was a statistically significant positive interaction between previous delivery of a SGA infant and previous preeclampsia (p = 0.01): Women with this combination in their first pregnancy had an approximately fivefold risk of unexplained stillbirth in the second pregnancy (HR = 4.95, 95% CI: 2.63, 9.32). Associations were stronger with SGA unexplained stillbirths. The authors conclude that complicated first births of liveborn infants are associated with an increased risk of unexplained stillbirth in the next pregnancy.

Confidence Intervals↗
PubMed1999

Postnatal time frame for renal vulnerability to enalapril in rats.

Angiotensin-converting enzyme inhibition or angiotensin II type 1 receptor blockade in neonatal, but not in weaned, rats induces irreversible renal histologic abnormalities and an impaired urinary concentrating ability. The aim of the present study was to define the postnatal time frame when the rat kidney is vulnerable to an interruption of the renin-angiotensin system. Male Wistar rats received daily injections of enalapril (10 mg/kg, intraperitoneally) during different age intervals within 3 to 24 d,of age. Fluid handling and urinary concentrating ability, renal function under pentobarbital anesthesia, and kidney histology using stereologic techniques were evaluated in adult rats. Enalapril treatment within 3 to 13 d after birth induced abnormalities in renal function and morphology long-term, whereas treatment initiated at 14 d of age did not. The main histologic alterations were papillary atrophy, and a reduction in the volume of tubular epithelial cells in association with an increase in the proportion of interstitium, throughout the cortex and outer medulla. Functionally, the predominant defect was an impairment in urinary concentrating ability, which correlated with the degree of papillary atrophy. In conclusion, the vulnerable age interval for the induction of irreversible renal abnormalities by enalapril was the first 13 d after birth in the rat. This postnatal time span coincides with the completion of nephrogenesis and a period of marked tubular growth and differentiation, suggesting a pivotal role for angiotensin II in these processes.

Age Factors↗
PubMed2004

Collaborative quality improvement to promote evidence based surfactant for preterm infants: a cluster randomised trial.

OBJECTIVE: To test a multifaceted collaborative quality improvement intervention designed to promote evidence based surfactant treatment for preterm infants of 23-29 weeks' gestation. DESIGN: Cluster randomised controlled trial. SETTING AND PARTICIPANTS: 114 neonatal intensive care units (which treated 6039 infants of 23-29 weeks gestation born in 2001). MAIN OUTCOME MEASURES: Process of care measures: proportion of infants receiving first surfactant in the delivery room, proportion receiving first surfactant more than two hours after birth, and median time from birth to first dose of surfactant. Clinical outcomes: death before discharge home, and pneumothorax. INTERVENTION: Multifaceted collaborative quality improvement advice including audit and feedback, evidence reviews, an interactive training workshop, and ongoing faculty support via conference calls and email. RESULTS: Compared with those in control hospitals, infants in intervention hospitals were more likely to receive surfactant in the delivery room (adjusted odds ratio 5.38 (95% confidence interval 2.84 to 10.20)), were less likely to receive the first dose more than two hours after birth (adjusted odds ratio 0.35 (0.24 to 0.53)), and received the first dose of surfactant sooner after birth (median of 21 minutes v 78 minutes, P < 0.001). The intervention effect on timing of surfactant was larger for infants born in the participating hospitals than for infants transferred to a participating hospital after birth. There were no significant differences in mortality or pneumothorax. CONCLUSION: A multifaceted intervention including audit and feedback, evidence reviews, quality improvement training, and follow up support changed the behaviour of health professionals and promoted evidence based practice.

Cluster Analysis↗
PubMed1989

Intestinal transmission of macromolecules in newborn dairy calves of different ages at first feeding.

Four groups of eight newborn calves were used to study the intestinal transmission of colostral immunoglobulin from the intestinal lumen to the blood circulation. The first feed was given one, eight, 16 or 24 hours after birth. Thereafter, three feeds were given with eight hour intervals. All feeds were from the same pool of colostrum and the amount fed each time corresponded to 3 per cent of the calves birthweight. To estimate the transmission of macromolecules in each feed four different macromolecules were used as markers. For the first feed, the marker was bovine IgG, in the second FITC-dextran, in the third ovalbumin and in the fourth human serum albumin. Blood samples were taken eight hours after each feed and at one week old. There were no differences in transmission for the first feed although the calves varied in age between one and 24 hours, but in the second, third and fourth feeds the calves that received a first feed at one hour old, transmitted significantly more of the marker molecules than did the other three groups. The substantial transmission of macromolecules at the first feed in all four groups indicates that a base level of transmission capacity is maintained during the first 24 hours or longer and that, under certain conditions, acceptable passive immunisation is possible in calves given their first colostrum as late as 24 hours after birth.

Animals↗