Related Articles

Objectives

Our aim was to establish whether there is an interconnection between the compositional development of the gut microbiota and the amount of fussing and crying in early infancy.

Methods

Behavioral patterns of 89 infants during the 7th and 12th week of life were recorded in parental diaries. Total distress was defined as the sum of daily amounts of crying and fussing. Infants' gut microbiota profiles were investigated by several molecular assays during the first six months of life.

Results

The median (range) duration of total distress among the infants was 106 (0–478) minutes a day during the 7th and 58 (0–448) minutes a day during the 12th week. The proportion of Bifidobacterium counts to total bacterial counts was inversely associated with the amount of crying and fussing during the first 3 months of life (p = 0.03), although the number of Bifidobacterium breve was positively associated with total distress (p = 0.02). The frequency of Lactobacillus spp. at the age of 3 weeks was inversely associated with total infant distress during the 7th week of life (p = 0.02).

Conclusions

Bifidobacterium and Lactobacillus appear to protect against crying and fussing. Identification of specific strains with optimal protective properties would benefit at-risk infants.

Introduction:

Few convincing treatment options have been identified for the excessively crying infant. One explanation may be a lack of identification of patient subgroups. This study used a clinically plausible categorization protocol to subgroup infants and compared changes in symptoms between these subgroups during treatment.

Methods:

An observational cohort design was employed. All infants presenting with excessive infant crying between July 2007 and March 2008 were categorized into three subgroups, (A) infant colic, (B) irritable infant syndrome of musculoskeletal origin (IISMO) and (C) inefficient feeding crying infants with disordered sleep (IFCIDS) based on history and physical findings. Mothers completed questionnaires which rated their own and their child’s characteristics prior to and at the end, of a course of manual therapy. Independent associations between infant subgroups and changes in continuous outcomes (crying, stress, sleep, and consolability) were assessed. Multivariable analysis of covariance was used to identify and control for potential confounders.

Results:

A total of 158 infants were enrolled. There was no significant difference in demographic profile between groups or any significant difference in infant crying or level of maternal stress at the start. Only the putative subgroups were significantly associated with differences in outcomes. In general, colic babies improved the most in consolability and crying.

Conclusion:

Babies with excessive crying should not be viewed as a homogenous group. Treatment outcomes may be improved by targeting appropriate subgroups prior to treatment.

Sleep-wake behaviors and temperament were examined longitudinally for trait stability and relationship to behavioral state regulation from infancy to early childhood. Subjects were 120 low-risk, full-term infants from a middle class sample. At 6 weeks, parents completed 3 consecutive days of the Baby’s Day Diary which measures sleep, wake, fuss, feed and cry states and the Infant Characteristics Questionnaire. At 16 months, parents assessed sleep behaviors with the Sleep Habits Inventory and temperament with the Toddler Symptom Checklist. At 24 months, parents repeated 3 days of the Baby’s Day Diary. Structural Equation Modeling was used to examine cross-age hypotheses for sleep-wake and temperament associations. From early infancy to toddlerhood, sleep-wake behaviors and irritable temperament were notably stable but independent in this cohort.

Despite their common use parental diaries of infants' cry and fuss behaviour have not been compared with objective methods of recording. To understand what is meant by the descriptions of crying and fussing in the diaries, the diaries of 10 mothers of 6 week old infants were compared with tape recordings of vocalisations made by the babies over a 24 hour period. There were moderately strong correlations between the frequency of episodes (clusters of 'negative vocalisations') on the audiotape and episodes of 'crying and fussing' in the diaries, and between the duration of episodes on the audiotape and episodes of 'crying' in the diaries. To assess the acceptability of the diaries for recording information for clinical and epidemiological research, they were then used in a population study of a wide socioeconomic group. Usable data were obtained from 91% of the sample. The results suggest that despite pronounced differences between recording methods, these diaries may provide valid and useful reports of crying and fussing in the short term.

The mother of a 3-month old girl presented her daughter for chiropractic care with a medical diagnosis of gastroesophageal reflux disease. Her complaints included frequently interrupted sleep, excessive intestinal gas, frequent vomiting, excessive crying, difficulty breastfeeding, plagiocephaly and torticollis. Previous medical care consisted of Prilosec prescription medication. Notable improvement in the patient’s symptoms was observed within four visits and total resolution of symptoms within three months of care. This case study suggests that patients with complaints associated with both musculoskeletal and non-musculoskeletal origin may benefit from chiropractic care.

OBJECTIVES—To investigate the prevalence of infant crying and maternal soothing techniques in relation to ethnic origin and other sociodemographic variables.
DESIGN—A questionnaire survey among mothers of 2-3 month old infants registered at six child health clinics in Amsterdam, the Netherlands.
SUBJECTS—A questionnaire on sociodemographic characteristics and crying behaviour was completed for 1826 of 2180 (84%) infants invited with their parents to visit the child health clinics. A questionnaire on soothing techniques was also filled out at home for 1142 (63%) of these infants.
RESULTS—Overall prevalences of "crying for three or more hours/24 hour day", "crying a lot", and "difficult to comfort" were 7.6%, 14.0%, and 10.3%, respectively. Problematic infant crying was reported by 20.3% of the mothers. Of these infants, only 14% met all three inclusion criteria. Problematic crying occurred less frequently among girls, second and later born children, Surinamese infants, and breast fed infants. Many mothers used soothing techniques that could affect their infant's health negatively. Shaking, slapping, and putting the baby to sleep in a prone position were more common among non-Dutch (especially Turkish) mothers than among Dutch mothers. Poorly educated mothers slapped their baby more often than highly educated mothers.
CONCLUSIONS—Mothers' reports of infant crying and soothing varied sociodemographically. Much harm may be prevented by counselling parents (especially immigrants) on how and how not to respond to infant crying. Health education should start before the child's birth, because certain soothing techniques could be fatal, even when practised for the first time.



Infantile colic is one of the major challenges of parenthood. It is one of the common reasons parents seek medical advice during their child’s first 3 months of life. It is defined as paroxysms of crying lasting more than 3 hours a day, occurring more than 3 days in any week for 3 weeks in a healthy baby aged 2 weeks to 4 months. Colic is a poorly understood phenomenon affecting up to 30% of babies, underlying organic causes of excessive crying account for less than 5%. Laboratory tests and radiological examinations are unnecessary if the infant is gaining weight normally and has a normal physical examination. Treatment is limited and drug treatment has no role in management. Probiotics are now emerging as promising agents in the treatment of infantile colic. Alternative medicine (Herbal tea, fennel, glucose and massage therapy) have not proved to be consistently helpful and some might even be dangerous. In conclusion infantile colic is a common cause of maternal distress and family disturbance, the cornerstone of management remains reassurance of parents regarding the benign and self-limiting nature of the illness. There is a critical need for more evidence based treatment protocols.

Young children's temper tantrums offer a unique window into the expression and regulation of strong emotions. Previous work, largely based on parental report, suggests that two emotions, anger and sadness, have different behavioral manifestations and different time courses within tantrums. Individual motor and vocal behaviors, reported by parents, have been interpreted as representing different levels of intensity within each emotion category. The present study used high fidelity audio recordings to capture the acoustic features of children's vocalizations during tantrums. Results indicated that perceptually categorized screaming, yelling, crying, whining, and fussing each have distinct acoustic features. Screaming and yelling form a group with similar acoustic features while crying, whining, and fussing form a second acoustically related group. Within these groups, screaming may reflect a higher intensity of anger than yelling while fussing, whining and crying may reflect an increasing intensity of sadness.

Links between maternal emotional reactions to crying (anger and anxiety) and infant attachment security were examined in 119 mother-infant dyads. Mothers rated the intensity of their emotional responses to videotapes of crying infants prenatally. Maternal sensitivity was observed during infant exposure to emotion eliciting tasks at six and 16 months postpartum and mothers’ self-reported on their responses to their infant’s negative emotions at 16 months. Infant attachment security was assessed using the Strange Situation at 16 months postpartum. Results indicated that observed sensitivity was associated with fewer avoidant and resistant behaviors and prenatal maternal anger and anxiety in response to infant crying predicted the developing attachment system independent of observed sensitivity, but in different ways. Maternal anxiety in response to crying was positively associated with resistant behaviors as a direct effect. Maternal anger in response to crying was associated with avoidant behaviors indirectly through mothers’ self-reported punitive and minimizing responses to infant distress at sixteen months. Theoretical, applied and methodological implications are discussed.

Origins of mothers’ and fathers’ beliefs about infant crying were examined in 87 couples. Parents completed measures of emotion minimization in the family of origin, depressive symptoms, empathy, trait anger, and coping styles prenatally. At 6 months postpartum, parents completed a self-report measure of their beliefs about infant crying. Mothers endorsed more infant-oriented and less parent-oriented beliefs about crying than did fathers. Consistent with prediction, a history of emotion minimization was linked with more parent-oriented and fewer infant-oriented beliefs about infant crying for both mothers and fathers either as a main effect or in conjunction with the partners’ infant-oriented beliefs. Contrary to expectation, parents’ own emotional dispositions had little effect on parents’ beliefs about crying. The pattern of associations varied for mothers and fathers in a number of ways. Implications for future research and programs promoting sensitive parenting are discussed.

Background

Infant colic, characterised by excessive crying/fussing for no apparent cause, affects up to 20% of infants under three months of age and is a great burden to families, health professionals and the health system. One promising approach to improving its management is the use of oral probiotics. The Baby Biotics trial aims to determine whether the probiotic Lactobacillus reuteri DSM 17938 is effective in reducing crying in infants less than three months old (<13.0 weeks) with infant colic when compared to placebo.

Methods/Design

Design: Double-blind, placebo-controlled randomised trial in Melbourne, Australia. Participants: 160 breast and formula fed infants less than three months old who present either to clinical or community services and meet Wessel’s criteria of crying and/or fussing. Intervention: Oral once-daily Lactobacillus reuteri (1x108 cfu) versus placebo for one month. Primary outcome: Infant crying/fussing time per 24 hours at one month. Secondary outcomes: i) number of episodes of infant crying/fussing per 24 hours and ii) infant sleep duration per 24 hours (at 7, 14, 21, 28 days and 6 months); iii) maternal mental health scores, iv) family functioning scores, v) parent quality adjusted life years scores, and vi) intervention cost-effectiveness (at one and six months); and vii) infant faecal microbiota diversity, viii) infant faecal calprotectin levels and ix) Eschericia coli load (at one month only). Analysis: Primary and secondary outcomes for the intervention versus control groups will be compared with t tests and non-parametric tests for continuous data and chi squared tests for dichotomous data. Regression models will be used to adjust for potential confounding factors. Intention-to-treat analysis will be applied.

Discussion

An effective, practical and acceptable intervention for infant colic would represent a major clinical advance. Because our trial includes breast and formula-fed babies, our results should generalise to most babies with colic. If cost-effective, the intervention’s simplicity is such that it could be widely taken up as a new standard of care in the primary and secondary care sectors.

Trial Registration

Current Controlled Trials ISRCTN95287767

Objective

Infants who cry a lot, or are unsettled in the night, are common sources of concern for parents and costly problems for health services. The two types of problems have been linked together and attributed to a general disturbance of infant regulation. Yet the infant behaviours involved present differently, at separate ages and times of day. To clarify causation, this study aims to assess whether prolonged crying at 5–6 weeks (the peak age for crying) predicts which infants are unsettled in the night at 12 weeks of age (when most infants become settled at night).

Methods

Data from two longitudinal studies are analysed. Infant crying data were obtained from validated behaviour diaries; sleep-waking data from standard parental questionnaires.

Results

A significant, weak relationship was found between crying at 5–6 weeks and 12-week night waking and signalling in one study, but not the other. Most infants who met the definition for prolonged crying/colic at 5–6 weeks were settled during the night at 12 weeks of age; they were not more likely than other infants to be unsettled.

Conclusions

Most infants who cry a lot at 5–6 weeks of age ‘sleep through the night’ at 12 weeks of age. This adds to evidence that the two types of problematic behaviour have different causes, and that infant sleep-waking problems usually involve maintenance of signalling behaviours rather than a generalised disturbance.

We evaluated the effectiveness of SleepTight in the management of infant colic. SleepTight is a device that vibrates the infant's crib to simulate the action of a car traveling at 55 mph. A multiple baseline design across 6 infants was used. Data were collected on infant crying, parental use of SleepTight, and parental satisfaction. The application of SleepTight was associated with reduction in crying in 4 of the 6 infants. These outcome data notwithstanding, consideration of reported nonrecording of severe episodes and mixed reports of satisfaction suggests that SleepTight may not be a viable means of managing infant colic.

In a prospective follow up of 116 high risk infants, a 24 hour behavioural chart on seven consecutive days was analysed at seven and 12 weeks of age. Of children who manifested atopic disease at 2 years, 44/116 (38%), had shown significantly more fussing during the seventh, and colic type cry during the twelfth week than those who remained healthy (72/116, 62%).



Background: Long term studies of cognitive development and colic have not differentiated between typical colic and prolonged crying.

Objective: To evaluate whether colic and excessive crying that persists beyond 3 months is associated with adverse cognitive development.

Design: Prospective cohort study. A sample of 561 women was enrolled in the second trimester of pregnancy. Colic and prolonged crying were based on crying behaviour assessed at 6 and 13 weeks. Children's intelligence, motor abilities, and behaviour were measured at 5 years (n = 327). Known risk factors for cognitive impairment were ascertained prenatally, after birth, at 6 and 13 weeks, at 6, 9, and 13 months, and at 5 years of age.

Results: Children with prolonged crying (but not those with colic only) had an adjusted mean IQ that was 9 points lower than the control group. Their performance and verbal IQ scores were 9.2 and 6.7 points lower than the control group, respectively. The prolonged crying group also had significantly poorer fine motor abilities compared with the control group. Colic had no effect on cognitive development.

Conclusions: Excessive, uncontrolled crying that persists beyond 3 months of age in infants without other signs of neurological damage may be a marker for cognitive deficits during childhood. Such infants need to be examined and followed up more intensively.

According to the commonest definition, infant colic is distinguished by crying which is 'paroxysmal'-that is, intense and different in type from normal fussing and crying. To test this, maternal reports of the distress type of 67 infants whose fuss/crying usually exceeded three hours a day ('persistent criers') were scrutinised using 24 hour audiorecordings of the infants' distressed vocalisation. 'Moderate criers' (n = 55) and 'evening criers' (n = 38) were also assessed. Most of the distress in all three groups was fussing. In the audiorecordings the persistent criers showed a higher crying: fussing ratio than the moderate criers, but intense crying was rare. A third of the persistent criers were reported by their mothers to have occasional, distinct colic bouts of 'intense, unsoothable crying and other behaviour, perhaps due to stomach or bowel pain.' In the audiorecordings these periods were longer, but not paroxysmal in onset or more intense than the crying of persistent criers not judged to have colic. The audible features of the crying may be less important than its unpredictable, prolonged, hard to soothe, and unexplained nature.

AIM: To assess the incidence of infantile colic and its association with variable predictors in infants born in a community maternity hospital, Tehran, Iran.

METHODS: In this prospective cohort study, mothers who gave birth to live newborns between February 21 and March 20, 2003 at the hospital were invited to join to the study. For every infant-mother dyad data were collected on infant gender, type of delivery, gestational age at birth, birth weight, birth order, and mother’s reproductive history. Then mothers were given a diary to document the duration of crying/fussiness behaviors of their infants for the next 12 wk. We scheduled home visits at the time the infants were 3 mo of age to collect the completed diaries and obtain additional information on infants’ nutritional sources and identify if medications were used for colic relief. Cases of colic were identified by applying Wessel criteria to recorded data. Chi-square and Mann-whitney U tests were used to compare proportions for non-parametric and parametric variables, respectively.

RESULTS: From 413 infants, follow-up was completed for 321 infants. In total, 65 infants (20.24%) satisfied the Wessel criteria for infantile colic. No statistical significance was found between colicky and non-colicky infants according to gender, gestational age at birth, birth weight, type of delivery, and, infant’s feeding pattern. However, firstborn infants had higher rate for developing colic (P = 0.03).

CONCLUSION: Colic incidence was 20% in this population of Iranian infants. Except for birth order status, no other variable was significantly associated with infantile colic.

AIMS—To investigate (1) whether colic cries are acoustically distinct from pre-feed "hunger" cries; (2) the role of the acoustic properties of these cries versus their other properties in accounting for parents' concerns about colic.
DESIGN—From a community sample, infants were selected who met Wessel colic criteria for amounts of crying and whose mothers identified colic bouts. Using acoustic analyses, the most intense segments of nine colic bouts were compared with matched segments from pre-feed cries presumed to reflect hunger.
RESULTS—The colic cries did not have a higher pitch or proportion of dysphonation than the pre-feed cries. They did contain more frequent shorter utterances, but these resembled normal cries investigated in other studies. There is no evidence that colic cries have distinct acoustic features that are reproducible across samples and studies, which identify a discrete clinical condition, and which are identified accurately by parents.
CONCLUSIONS—The most reliable finding is that colic cries convey diffuse acoustic and audible information that a baby is highly aroused or distressed. Non-acoustic features, including the prolonged, hard to soothe, and unexplained nature of the cries may be specific to colic cries and more important for parents. These properties might reflect temperament-like dispositions.



Objective: To evaluate the effectiveness of diets, drug treatment, and behavioural interventions on infantile colic in trials with crying or the presence of colic as the primary outcome measure.

Data sources: Controlled clinical trials identified by a highly sensitive search strategy in Medline (1966-96), Embase (1986-95), and the Cochrane Controlled Trials Register, in combination with reference checking for further relevant publications. Keywords were crying and colic.

Study selection: Two independent assessors selected controlled trials with interventions lasting at least 3 days that included infants younger than 6 months who cried excessively.

Data synthesis: Methodological quality was assessed by two assessors independently with a quality assessment scale (range 0-5). Effect sizes were calculated as percentage success. Effect sizes of trials using identical interventions were pooled using a random effects model.

Results: 27 controlled trials were identified. Elimination of cows’ milk protein was effective when substituted by hypoallergenic formula milks (effect size 0.22 (95% confidence interval 0.09 to 0.34)). The effectiveness of substitution by soy formula milks was unclear when only trials of good methodological quality were considered. The benefit of eliminating cows’ milk protein was not restricted to highly selected populations. Dicyclomine was effective (effect size 0.46 ( 0.33 to 0.60)), but serious side effects have been reported. The advice to reduce stimulation was beneficial (effect size 0.48 (0.23 to 0.74)), whereas the advice to increase carrying and holding seemed not to reduce crying. No benefit was shown for simethicone. Uncertainty remained about the effectiveness of low lactose formula milks.

Conclusions: Infantile colic should preferably be treated by advising carers to reduce stimulation and with a one week trial of a hypoallergenic formula milk.

Key messages Infantile colic is common during the first months of life, but its cause is unknown A definite diagnosis of infantile colic should be followed by a one week trial of substituting cows’ milk with hypoallergenic formula milk Dietary intervention should be combined with behavioural interventions: general advice, reassurance, reduction in stimuli, and sensitive differential responding (teaching parents to be more appropriately responsive to their infants with less overstimulation and more effective soothing) Anticholinergic drugs are not recommended because of their serious side effects

Aims: To examine the relation between colic and feeding difficulties and their impact on parental functioning for a primarily clinic referred sample.

Methods: Forty three infants (and their mothers) were enrolled between 6 and 8 weeks of age. Infants were divided into two groups, colic (n = 19) and comparison (n = 24), based on a modified Wessel rule of three criteria for colic. Families were assessed at two visits; one occurred in the laboratory and one occurred in a paediatric radiology office. Outcome measures included the clinical assessment of infant oral motor skills, behavioural observation of mother-infant feeding interactions, maternal questionnaires on infant crying, sleeping and feeding behaviours, and the occurrence of gastro-oesophageal reflux (GOR) in the infants using abdominal ultrasound.

Results: Infants in the colic group displayed more difficulties with feeding; including disorganised feeding behaviours, less rhythmic nutritive and non-nutritive sucking, more discomfort following feedings, and lower responsiveness during feeding interactions. Infants in the colic group also had more evidence of GOR based on the number of reflux episodes on abdominal ultrasound as well as maternal report of reflux. Mothers in the colic group reported higher levels of parenting stress.

Conclusions: Results provide the first systematic evidence of feeding problems in a subgroup of infants with colic. Data also illustrate the impact of these difficulties on parental and infant functioning. The association between feeding difficulties and colic suggests the potential for ongoing regulatory problems in infants presenting with clinically significant colic symptoms.

With an increase in the prevalence of overweight being seen as early as infancy, it is essential that the factors which account for early excess weight gain be identified. In this study, maternal and infant characteristics were examined to determine their relation to the frequency of infants being fed. A cohort of 67 low-educated Mexican mothers who formula-fed their infants were recruited at a WIC Center and home-visited when their infants were 6-months-old. Mothers were surveyed with regard to their feeding attitudes and perception of their infant’s temperament, and kept a 24-hour diary of their infant’s behavior. Nearly 30% of the 6-month-old infants were at or above the 85th percentile of weight-for length. A regression analysis revealed only one factor, the number of infant crying episodes, as predictive of infant feeding (Beta = .246, p<.07), with the correlation even stronger (r =.35 (p<.01). As crying appeared to elicit feeding among these mothers, pediatricians, nurses, and WIC educators should consider discussing alternate strategies for quieting infants with the mothers they counsel.

Background: Infants with neonatal cerebral insults are susceptible to excessive crying as a result of difficulties with self-regulation.

Aims: To compare the effectiveness of swaddling versus massage therapy in the management of excessive crying of infants with cerebral insults.

Methods: Randomised three-week parallel comparison of the efficacy of two intervention methods. Infants with symptoms of troublesome crying and their parents were randomly assigned to a swaddling intervention group (n = 13) or a massage intervention group (n = 12).

Results: The amount of total daily crying decreased significantly in the swaddling group, but did not decrease significantly in the massage group. Infant behavioural profiles and maternal anxiety levels improved significantly in the swaddling group post-intervention. Parents in the swaddling group were more satisfied with the effectiveness of the intervention in reducing crying than parents in the massage group.

Conclusion: Results indicate that swaddling may be more effective than massage intervention in reducing crying in infants with cerebral injuries.

Background

Infant crying and sleep problems (e.g. frequent night waking, difficulties settling to sleep) each affect up to 30% of infants and often co-exist. They are costly to manage and associated with adverse outcomes including postnatal depression symptoms, early weaning from breast milk, and later child behaviour problems. Preventing such problems could improve these adverse outcomes and reduce costs to families and the health care system. Anticipatory guidance-i.e. providing parents with information about normal infant sleep and cry patterns, ways to encourage self-settling in infants, and ways to develop feeding and settling routines before the onset of problems-could prevent such problems. This paper outlines the protocol for our study which aims to test an anticipatory guidance approach.

Methods/Design

750 families from four Local Government Areas in Melbourne, Australia have been randomised to receive the Baby Business program (intervention group) or usual care (control group) offered by health services. The Baby Business program provides parents with information about infant sleep and crying via a DVD and booklet (mailed soon after birth), telephone consultation (at infant age 6-8 weeks) and parent group session (at infant age 12 weeks). All English speaking parents of healthy newborn infants born at > 32 weeks gestation and referred by their maternal and child health nurse at their first post partum home visit (day 7-10 postpartum), are eligible. The primary outcome is parent report of infant night time sleep as a problem at four months of age and secondary outcomes include parent report of infant daytime sleep or crying as a problem, mean duration of infant sleep and crying/24 hours, parental depression symptoms, parent sleep quality and quantity and health service use. Data will be collected at two weeks (baseline), four months and six months of age. An economic evaluation using a cost-consequences approach will, from a societal perspective, compare costs and health outcomes between the intervention and control groups.

Discussion

To our knowledge this is the first randomised controlled trial of a program which aims to prevent both infant sleeping and crying problems and associated postnatal depression symptoms. If effective, it could offer an important public health prevention approach to these common, distressing problems.

Trial registration number

ISRCTN: ISRCTN63834603

Parents commonly seek clinicians' help for infant crying that they judge to be excessive. To date there is no independent evidence whether such babies actually cry more than average. To assess this, maternal diary and 24 hour audiotape recordings of the crying periods of 16 infants referred for excessive crying were compared with equivalent measures of a normative sample. The overall amounts of crying measured by the two methods were similar. The referred infants cried substantially more over 24 hours and in the afternoon and evening. The difference approached significance in the morning but was insignificant at night time. Some qualifications to the findings are indicated.

Breath hydrogen excretion as an index of incomplete lactose absorption was measured in 118 healthy infants who were either breast fed or given a formula feed containing lactose, some of whom had colic. Infants with colic (n = 65) were selected on the basis of the mother's report of a history of inconsolable crying lasting several hours each day. Infants in the control group (n = 53) were not reported to cry excessively by their mothers. Breath samples were collected using a face mask sampling device preprandially, and 90 and 150 minutes after the start of a feed. Normalised breath hydrogen concentrations were higher in the group with colic than in the control group at each time point. The median maximum breath hydrogen concentration in the colic group was 29 ppm, and in the control group 11 ppm. The percentage of infants with incomplete lactose absorption (breath hydrogen concentration more than 20 ppm) in the colic group was 62% compared with 32% in the control group. The clinical importance of the observed association between increased breath hydrogen excretion and infantile colic remains to be determined. Increased breath hydrogen excretion indicative of incomplete lactose absorption may be either a cause or an effect of colic in infants.