Biomedical subjects

M W Woolridge

Publications and source records attributed to M W Woolridge.

At least 19 recordsLinked to original sources

PubMed2001

Treatments for breast engorgement during lactation.

BACKGROUND: National surveys have shown that painful breasts are the second most common reason for giving up breastfeeding in the first two weeks after birth in the UK. One factor contributing to such pain can be breast engorgement. Views differ as to how engorgement arises, although restrictive feeding patterns in hospital are likely to have contributed in the past. These differing views are reflected in the range of solutions offered to treat engorgement in breastfeeding mothers and these treatments are assessed in this review. OBJECTIVES: To determine the effects of any proposed intervention to relieve symptoms of breast engorgement among breastfeeding women. SEARCH STRATEGY: The register of clinical trials maintained and updated by the Cochrane Pregnancy and Childbirth Group. CINAHL and MEDLINE were also searched. Date of last search: December 2000. SELECTION CRITERIA: All randomised and 'quasi-randomised' controlled trials, with or without blinding, that assess the effectiveness of treatments for the alleviation of symptoms in breastfeeding women experiencing engorgement. DATA COLLECTION AND ANALYSIS: Data were extracted by one reviewer and verified by a second reviewer. MAIN RESULTS: Eight trials, involving 424 women, were included. Three different studies were identified which used cabbage leaves or cabbage leaf extracts;. no overall benefit was found. Ultrasound treatment and placebo were equally effective. Use of Danzen (an anti-inflammatory agent) significantly improved the total symptoms of engorgement when compared to placebo (odds ratio (OR) 3.6, 95% confidence interval (CI) 1.3 - 10.3) as did bromelain/trypsin complex (OR 8.02, 95% CI 2.8-23.3). Oxytocin and cold packs had no demonstrable effect on engorgement symptoms. REVIEWER'S CONCLUSIONS: Cabbage leaves and gel packs were equally effective in the treatment of engorgement. Since both cabbage extract and placebo cream were equally effective, the alleviation in symptoms may be brought about by other factors, such as breast massage. Ultrasound treatment is equally effective with or without the ultra-wave emitting crystal, therefore its effectiveness is more likely to be due to the effect of radiant heat or massage. Pharmacologically, oxytocin was not an effective engorgement treatment while Danzen and bromelain/trypsin complex significantly improved the symptoms of engorgement. Initial prevention of breast engorgement should remain the key priority.

Breast Diseases↗

PubMed2001

Factors affecting the transfer of organochlorine pesticide residues to breastmilk.

Existing studies monitoring organochlorine pesticide residues in breastmilk were examined to identify whether common factors determine the extent of transfer of these residues. A structured review of the English language literature was conducted. Papers were reviewed and assessed using a structured protocol. A total of 77 papers were initially identified, 46 of which contained conclusions relating to the factors which may affect the transfer of residues into breastmilk. Owing to the diversity of findings, papers were screened further to include only those in which a minimum of background information relating to selection of mothers and to milk sampling procedures were reported. Only eight papers were deemed to contain adequate information. Age, parity/length of previous lactation, fat mobilisation and the time of sampling were identified as the most likely factors to be considered when assessing transfer of organochlorine pesticide residues into breastmilk. This review highlights the difficulties of assessing trends in breastmilk contaminants where comparable sampling procedures are not used.

Age Factors↗

PubMed2001

Assessing the risks of pesticide residues to consumers: recent and future developments.

Assessing exposure of consumers to pesticide residues is an area of regulatory science that has rapidly developed over the last decade. From simplistic, deterministic models calculating lifetime exposure for adults only, assessment procedures have diversified so that more realistic estimates of long term exposures for adults, schoolchildren, toddlers and infants and short term exposures for adults and toddlers (who generally bound the more extreme consumer patterns) are now carried out. The final assessment of risk still remains a simplistic numeric comparison against hazard assessment based on a wide range of toxicity studies incorporating the appropriate safety or uncertainty factors. As development of risk assessments continues, the use of probabilistic models is becoming an invaluable information tool for quantitative risk management and aiding assessment of cumulative exposure. This paper examines the recent developments in risk assessment and consumer perception of the risks of pesticide residues, and speculates where the future developments in these areas may lie.

Adolescent↗

PubMed2000

Early versus delayed initiation of breastfeeding.

EDITORIAL NOTE: This review has been withdrawn because it is out of date. The topic will be covered by a new review, 'The effect of the timing of feedings on the establishment of breastfeeding', the protocol for which is currently being prepared. BACKGROUND: It has been suggested that the timing of a baby's first breastfeed may influence breastfeeding duration and emotional attachment. OBJECTIVES: The objective of this review was to assess the effects of breastfeeding soon after birth (within 30 minutes) compared to being breastfed later (between 4 to 8 hours after delivery) on the duration of breastfeeding and the mother/infant relationship. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register. SELECTION CRITERIA: Randomised and quasi-randomised trials comparing early skin contact and breastfeeding with late skin contact and breastfeeding in women intending to breastfeed their healthy term infant. DATA COLLECTION AND ANALYSIS: Data were extracted by two reviewers. MAIN RESULTS: Three studies involving 209 women were included. Compared with late contact and breastfeeding, early contact and breastfeeding was associated with greater communication between mother and infants in a two minute observation period (odds ratio 0.14, 95% confidence interval 0.03 to 0.61). There was no difference detected for numbers of women breastfeeding after birth (odds ratio for 12 weeks after birth 0.73, 95% confidence interval 0.34 to 1.54). REVIEWER'S CONCLUSIONS: No differences were found between early and delayed contact in regard to breastfeeding duration. Early contact was associated with greater communication between mothers and infants.

Breast Feeding↗

PubMed2000

Feeding schedules in hospitals for newborn infants.

BACKGROUND: Regular breastfeeding times have been thought to help establish routines and promote infant digestion, while frequent breastfeeding has been recommended to enhance breastfeeding and infant growth. OBJECTIVES: The objective of this review was to assess the effects of frequent breastfeeding compared with less frequent breastfeeding in the early days after birth. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register. SELECTION CRITERIA: Randomised and quasi-randomised trials comparing on demand or frequent breastfeeding (two or three hourly) schedules in hospital compared with four hourly restricted feeds. DATA COLLECTION AND ANALYSIS: Trial quality was assessed and data were extracted independently by two reviewers. MAIN RESULTS: Three trials involving 400 women were included. There were significant methodological limitations in some of the studies. Compared to two hourly, three hourly or on demand breastfeeding, restricted (less frequent four hourly breastfeeding) was associated with greater discontinuation of breastfeeding by four to six weeks postpartum (relative risk 1.53, 95% confidence interval 1.08 to 2.15). Restricted breastfeeding was associated with increased incidence of sore nipples (relative risk 2.12, 95% confidence interval 1.22 to 3.68), engorgement (relative risk 2.10, 95% confidence interval 1.25 to 3.21) and the need to give additional (formula) feeds (relative risk 3.14, 95% 1.24 to 8.00). REVIEWER'S CONCLUSIONS: There appear to be a number of disadvantages from restricting breastfeeding to a four hourly schedule in the first few days after birth. More frequent or on demand breastfeeding is associated with fewer complications and longer duration of breastfeeding.

Breast Feeding↗

PubMed2000

Commercial hospital discharge packs for breastfeeding women.

BACKGROUND: Exclusive breastfeeding until around six months of age, followed by the introduction of solids with continued breastfeeding, is considered to be the optimal nutritional start for newborn infants. OBJECTIVES: To determine whether the exclusivity and duration of breastfeeding is affected by giving mothers commercial discharge packs in hospital which contain artificial formula or promotional material for artificial formula. These packs are those which are commonly given to mothers on leaving hospital after giving birth (thus discharge packs). SEARCH STRATEGY: Comprehensive electronic search of the register of clinical trials maintained and updated by the Cochrane Pregnancy and Childbirth Group and CINAHL and MEDLINE. SELECTION CRITERIA: All randomised controlled trials with or without blinding to examine the effects of commercial discharge packs on breastfeeding. PARTICIPANTS: Consenting postpartum women who initiate breastfeeding while in hospital or immediately upon discharge. INTERVENTIONS: Commercial discharge packs which contain free samples of infant formula or promotional material versus non commercial discharge packs (specifically those from which free samples of infant formula have been removed or have been replaced with e.g. breast pads) or no pack. MAIN OUTCOME MEASURES: The proportion of women breastfeeding at six weeks and 3 months (13 weeks) postpartum. Other outcomes: Rates of breastfeeding at other fixed time points between 0 and 6 months postpartum. DATA COLLECTION AND ANALYSIS: Data were extracted by one reviewer and checked by a second reviewer. MAIN RESULTS: Nine randomised controlled trials involving a total of 3730 women were analysed. The studies only included women from North America. The meta-analysis showed that when comparing commercial discharge packs with any of the controls (no intervention, non-commercial pack and combinations of these), exclusive breastfeeding was reduced at all time points in the presence of commercial hospital discharge packs. There was no evidence to support the conjecture that use of hospital discharge packs causes the early termination of non-exclusive breastfeeding. Where the introduction of solid food was measured, giving a commercial pack (with or without formula) reduced the time before solid food was introduced. REVIEWER'S CONCLUSIONS: The giving of commercial hospital discharge packs (with or without formula) appears to reduce the number of women exclusively breastfeeding at all times but has no significant effect upon the earlier termination of non-exclusive breastfeeding.

Breast Feeding↗

PubMed1999

Maternal predictors of early breast milk output.

Previous attempts to show a quantitative relationship between maternal hormone levels and early milk output have used small sample sizes and simple correlations. Women of mixed parity and similar socio-economic status and education were recruited to a study using multivariate analysis to look for these associations. Hormone levels (oestradiol, progesterone, prolactin and thyrotropin (TSH)) were determined for 91 mothers at four time points (ante- and postnatally) from finger-prick blood spots by fluoro-immunoassay. Milk output at 1 and 4 weeks was determined from 24-h test weighings. Parity was found to be the most significant factor affecting breast milk volume at 1 wk postpartum (multiparous women delivered 142 ml more milk in 24 h than primiparous women). Total time spent feeding had a strong association with breast milk volume, with increasing time having a negative effect. Multiple regression analysis, controlling for parity and time spent feeding, showed a positive association of milk output at 1 wk with antenatal progesterone and antenatal prolactin levels. At 4 wk, higher postpartum oestradiol levels had a negative association and antenatal progesterone levels a positive association with milk output. This study demonstrates that there are quantitative associations between antenatal maternal hormone levels and breast milk output in the early postnatal period.

Adult↗

PubMed1993

Recent advances in breast feeding.

Increasingly, epidemiological studies are showing the benefits of exclusive breast-feeding to infants in industrialized countries, as they have previously for those in developing countries. In this review we have focused on several recent developments, in particular on the interplay between infant behaviour and maternal physiology in regulating breast milk supply. This will illustrate that many past and current clinical problems concerning breast-feeding are likely to be of iatrogenic origin, the products of imposing arbitrary rules for breast-feeding management. In order for the protective benefits to be fully realized it is necessary to ensure that breast-feeding is free from prescriptive practices. We will illustrate the key role played by the infants' control of appetite in the hope of encouraging clinicians to empower infants to exercise more control over the feeding process.

Appetite Regulation↗

PubMed1990

Do changes in pattern of breast usage alter the baby's nutrient intake?

Twelve mother/baby pairs took part in a study of the difference in effect of two patterns of breast feeding--either feeding at one breast or at two breasts during a feed. Baseline measures were taken at 4 weeks, and the test patterns of feeding were followed for a week each, in random order. The two patterns of feeding led to differences in milk volume intake and mean feed fat concentration, but not in the baby's net fat intake per 24 h. The results indicate that the breast-fed baby can regulate his fat intake quickly and thus mothers should be encouraged to practice "baby-led" feeding.

Breast Feeding↗

PubMed1990

Alpha 1-microglobulin, beta 2-microglobulin and retinol binding protein in childhood febrile illness and renal disease.

Serum and urinary levels of alpha-1-microglobulin (A1M), beta-2-microglobulin (B2M) and retinol binding protein (RBP) were measured using a Mancini radial immunodiffusion technique in 52 children with renal disease, 36 with non-renal febrile illness and 29 controls. In controls the mean serum level for A1M was 25 +/- 4.6 (SD) mg/l for B2M 1.7 +/- 0.5 mg/l and for RBP 31 +/- 8 mg/l. A1M levels were not significantly altered by febrile illness while B2M was elevated and RBP markedly depressed. Serum A1M and B2M were elevated in the nephrotic syndrome, while serum B2M was also raised during infancy. Coefficients of log-transformed data with creatinine-derived glomerular filtration rate (GFR) were -0.87 for B2M, -0.71 for RBP, and -0.62 for A1M. In the urine A1M was always measurable in controls while B2M and RBP were undetectable in all but a small number. The urine levels of all three proteins increased in response to non-renal febrile illness, and rose invariably when GFR fell to below 40-50 ml/min per 1.73 m2. Of the three proteins A1M was most frequently elevated in the urine with febrile and renal illness. RBP was rarely detectable when the other two proteins were not. Urinary A1M was consistently elevated in the nephrotic syndrome in contrast to B2M, possibly as a reflection of the increased glomerular permeability. We conclude that serum B2M is superior to A1M and RBP as an index of glomerular filtration, although its levels should be interpreted with caution in febrile disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1990

Development of co-ordination of sucking, swallowing and breathing: ultrasound study of term and preterm infants.

Fourteen newborn babies of different gestational ages (33 to 40 weeks) but similar postnatal age (four to 19 days) were studied during bottle-feeding using real-time ultrasonography, combined with respiratory monitoring. Previously undescribed tongue movements and graded changes in the temporal relationships between tongue movements, swallowing and breathing were observed among infants of differing maturity. These were most marked in the least mature infants, but were occasionally seen in term infants. The results suggest that adequate neuromuscular co-ordination is more a function of gestational maturity than of postnatal sucking experience. The pattern of intraoral events for infants of differing maturity described in this study provides a framework for the study of feeding problems of term and preterm infants.

Bottle Feeding↗

PubMed1989

Stability of alpha 1-microglobulin, beta 2-microglobulin and retinol binding protein in urine.

The stability of alpha 1-microglobulin (alpha 1M), beta 2-microglobulin (beta 2M) and retinol binding protein (RBP) in urine was determined in 135 random samples from children with renal disease, febrile illness, malignancy, and from controls. Immediately after voiding, samples were divided into two portions, one of which was alkalinized. After identical transit times and laboratory handling the pH and concentrations of the individual proteins in each pair were measured. beta 2M was unstable in urine of pH less than 7 and grossly so below pH 6. In some instances beta 2M was low or undetectable even in the alkalinized samples when alpha 1M and RBP levels were raised, suggesting that degradation of beta 2M may have occurred prior to voiding. Concentrations of alpha 1M and RBP were significantly lower in the non-alkalinized fractions at pH less than 7, although to lesser degree than for beta 2M. Contrary to previous reports, we conclude that the stability of all 3 proteins is affected by urinary pH and recommend that this be measured and alkalinisation performed at the time of voiding.

Alpha-Globulins↗

PubMed1989

Relationships between nursing patterns, supplementary food intake and breast-milk intake in a rural Thai population.

Relationships between nursing patterns, supplementary food intake and breast-milk intake were examined in a group of 52 Thai babies under 1 year of age. All data were collected over two consecutive days, 24 h/day. Total sucking time (min/day) and supplementary food intake (kcal/day) were significant predictors of breast-milk intake after allowing for the age of the baby: R-squared is 0.32 for sucking time and 0.39 for supplementary food intake. The two variables were themselves correlated (r is -0.47). The number of breastfeeds per day and their mean duration was determined for each case, counting each episode of attachment to the breast as a separate feed. Number and mean duration of breastfeeds were then evaluated as predictor variables. The duration of feeds had no predictive power. Number of feeds was linearly related to milk intake and combined with age was as good a predictor of milk intake as total sucking time (with R-squared 0.34). These results suggest that a simple count of breastfeeds is as valuable as more complex measures of sucking duration in predicting to breast-milk intake.

Breast Feeding↗

PubMed1989

Predictors of breast milk intake in rural northern Thailand.

A random sample of 52 mothers and infants from a rural area of Northern Thailand were studied in their homes for 48 h. Infants were breast fed on demand. Daytime feeds were test weighed with electronic averaging balances and nighttime intake estimated using a new method, Indirect Test Weighing. All feeds, both day and night, were timed to the nearest minute. Other variables measured by direct observation were infant weight, and supplementary food and water intake. Mean 24-h breast milk intake was 579 g (range 78-1,011 g) with a median between day coefficient of variation of 8.8%. The proportion of 24-h breast milk intake consumed at night ranged from 8 to 91%, and increased with increasing infant age. Significant positive associations were found between breast milk intake, and sucking time and infant weight. There were significant negative associations between breast milk intake and age, and supplementary food and water intake.

Body Weight↗

PubMed1988

Colic, "overfeeding", and symptoms of lactose malabsorption in the breast-fed baby: a possible artifact of feed management?

Curtailing the time for which a baby feeds at the first breast, in order to encourage intake from the second breast, may maximise milk production by the mother. With escalation of this situation a point may be reached at which the infant, because of the constraint of his stomach capacity, is unable to consume sufficient calories at a feed, since foremilk is lower in calories than hindmilk. The result will be symptoms of hunger (crying, fretfulness) and maybe even failure to thrive. The low fat content of the diet may cause rapid gastric emptying. This in turn may lead to lactose reaching the small bowel in concentrations that may tax the infant's lactase potential, with resulting diarrhoea. A simple change in breastfeeding patterns may alleviate some instances of undernutrition or diarrhoea.

Breast Feeding↗

PubMed1988

Circadian variation in fat concentration of breast-milk in a rural northern Thai population.

1. Twenty-five northern Thai mothers, breast-feeding their infants on demand, were studied in their homes for 24 h. All breast-feeds were test-weighed and pre- and post-feed expressed breast-milk samples (0.5 ml) taken at each feed. 2. The fat concentration of milk taken during a feed showed significant circadian variation, with maximum values between 16.00 and 20.00 hours and minimum values between 04.00 and 08.00 hours. Fat concentration at the start and at the end of a feed also varied significantly over 24 h. 3. Multiple regression analysis showed that the most important predictor of fat concentration at a feed was the length of time elapsed since the previous feed--the longer this interval, the lower the subsequent fat concentration. Other significant predictors were the fat concentration at the end of the previous feed, and the milk intake at the previous and at the current feed. 4. Fat concentration declined between feeds in proportion to the length of time between feeds, but the decline was less between sleep feeds than between waking feeds. This would appear to be a reflection of the lower post-feed fat concentration and higher pre-feed fat concentration of sleep feeds compared with waking feeds, when other variables relating to feeding pattern are taken into account. 5. The larger the milk intake at a feed, the greater was the increase in fat concentration from the start to the end of the feed. The change in fat concentration was less in feeds taking place during the sleep period than in daytime feeds.

Adult↗

PubMed1988

Infant weight in relation to nutritional intake and morbidity in northern Thailand.

A cross-sectional study of 58 infants (age range 2-53 weeks) was carried out in a rural area of northern Thailand. Total dietary intake (energy and protein from breastmilk and supplementary food) was measured directly during continuous observation over 48 h of randomly selected study subjects in their homes. Associations between infant weight and total energy intake, total protein intake and morbidity were analysed by multiple regression analysis. Up to 6 months of age, heavier infants had larger energy intakes, when age and birthweight were taken into account. In the 7-12 months age group, heavier infants consumed more protein and had fewer respiratory infections. Weaned infants older than 6 months were significantly heavier and consumed more protein than infants of similar age who were still receiving breastmilk. The lower protein intakes of the latter infants were due to the low protein concentration of breastmilk compared with supplementary food.

Body Weight↗

PubMed1987

The automatic sampling shield: a device for sampling suckled breast milk.

The automatic sampling shield uses the negative pressure exerted by the breast-feeding baby during sucking to withdraw a series of small samples from the milk stream. Shield performance was studied at four feeds for each of 13 babies. Acceptance of the shield was good (96% of feeds) and samples were obtained in 88% of feeds. Sample weight was large enough for micro-biochemical analysis of composition (median weight 1.3 g), without depriving the baby of important amounts of milk (median percentage of weight of milk intake was 4.3% and sample weight was less than 5 g in all cases). The shield should sample a constant proportion throughout the feed, in order to obtain a sample that is representative of the infant's nutrient intake. Fractional test-weighing of feeds showed a tendency for a larger proportion of the feed to be collected at slower flow rates. Modelling on the basis of the observed flow profiles in conjunction with a theoretical fat concentration profile showed that the observed 'disproportionality' would have over-estimated fat intake by a mean of 2.6% per feed (S.D.9.1 range -18.9% to + 16.9%). Using the shield in random sequence at two out of the first four feeds after 0800 h, showed that an infant's mean milk intake with the shield was on average 32% less than on control feeds. Allowing for possible compensation by the infant when control feeds followed low shield intakes, mean milk intakes with the shield were 17% smaller than without the shield.

Breast Feeding↗