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Does the newborn baby find the nipple by smell?



We studied the involvement of naturally occurring odours in guiding the baby to the nipple. One breast of each participating mother was washed immediately after delivery. The newborn infant was placed prone between the breasts. Of 30 infants, 22 spontaneously selected the unwashed breast. The washing procedure had no effect on breast temperature. We concluded that the infants responded to olfactory differences between the washed and unwashed breasts.
O>10 weeks @>12
weeks a>18
+ 1.O SD
Mean + 1.8 SD and mean 2.O
+ SD
diagnosis are limited. If facilities are available, especially
during the first trimester, fetal DNA analysis of cr genes
still remains the method of choice.
I lai-Inio LE . Atpha-chlin thslassaemia bd hyatrops fetalis in Malaya:
repon offive cases.
alood t962120:581 91.
2 Todd D, lli MCS, BEsa CA. Thalassaemi. dd hy&ops fet iF
family studies. a {t 1967; 3: 347-52.
3 Thum.srlhir B, Nsd.sui. A, Silpisorukasol S. Hydrops fetalis
associ.ted with Ban\ haemoglobir in Nonh€m Thziland. J Pediorr
t9a6t73, \32 34.
4 !fi/€athe.sll
vons HB. The haemoslobin
constitution of
infants $'ith ha€moglobin Ban's hydrops fetalis s}aldrome. BrJ
Ha atol197Otlat 357-67 -
5 Li.ns ST, Vons V, So
"0K Ma HK, ChD V, Todd D. Homozysous
o-thalassaemia: €linical
diagnosis and management. A
review of46 cases. B/tObset Gtnae.ol l985j92t 6a0-a4.
6 Chan V, Ghosh A, Chan TK, Vong V, Todd D. Prenalal diaenosis of
d-thalassaenia by direct DNA Dalysis of ucultured
amniotic fluid €€lls. B/VJ 1984;244. t327 39.
7 Rubin EM, Kan YW. A simple sensirive
prenaral test for hydrops fetalis
c.used by o-thllassaemia - l9a5t i: 7 5-77 .
8 Hsieh FJ, Chang FM, Ko TM, Kuo Pr. Chans
DY, CbeD
HY. The
antenatal blood
and acid-base status ofnormal fetuses and
hydiopic feruses wirh Bart's hemoglobiDop{hy. Obrkt q)iecol rS89i
74t722 2t.
9 Kanokponssakdi S, Fucharoetr S, Varanasiri C, Thonslairosm P,
P, ManassakomJ.
UlEasonosrrphic merhods for
ofhaemoglobin Ban's hydrops feralis in $e second rimesrer
ofpregnancy. ,t'at Drap, 1990; 10:809 13.
lo Ghosh
A, Tang MHY, Liang ST, Ma HK Chan V, Chan TK.
Uhrasound evaluation of pregnancies
at risk for homozygous d-
thalassaemia- 1 . Irtaar D,iTr l9A7:7t 3O7 11.
among cases
Figure: Percentago of posltives
among cases
affocted by homozygous cr-thalassaeml+1) and controls
and o-thalassaemia-1
at dlfferent
at varlous cutdts of placental
12 weeks', a cut-off lower tlun mean plus 2 SD only
decreased specificiry wiLhour any increase
in sensitiviry.
Measurement of placental thickness du ng first and
second trimeste$ can differentiate normal ftom an
affected pregnancy in women at risk of giving birth to an
infant with homozygous cr-thalassaemia- l. A cut-off of
mean placental thickness plus 2 SD is appropriate. The
sensitivfty of placental drickness measulement in
derecting an affected pregnancy before 12 weeks'
gestation is low. In 2 pregnancies with a false-negative
result after 12 weeks' tie placentas were large on
ulrrasound, bur dickness was normal. With experience,
one should be able to recognise this tlpe ofplacenta. Both
these placentas were thought to be abnormal at the time
of amniocentesis. Measurement of placental volume
insread of thickness might be moie useful in dris situation.
However, in real-time sector scan, the whole length ofthe
placenta cannot be imaged during second trimester, and
volume measurement may be inaccurate.
Fetuses affected by homozygous c-thalassaemia-l
develop severe anaemia in early fetal life. This leads to
hydropic changes including an increase in placental
thickness and cardiomegaly. Increases in placental
thickness precede cardiomegaly.lo The increase in
placental rhickness occurred as early as the 10th
gestational week. !(/ith mean plus 2 SD, we could identifu
most affected pregnancies after 12 weeks and by 18
weeks' gestation, all affected pregnancies were detected.
Hence a normal placental thickness at or after the l8th
gestational week is reassuring and may obviate the need
for further invasive procedures to confrm normality.
An abnormal placental thickness is highly suggesrive
but not absolutely diagncistic of an affected pregnancy
and for earlier gestationr some of the abnormal
pregnancies could not be detected, Therefore invasive
diagnostic evaluation is necessary- Since the main
objective of prenatal diagnosis of homozygous o-
thalassaernia-l is reduction of maternal morbidity rather
tian prevention of birth of afected infants, serial
measurement of placental thickness may be an altemative
cost-effective method for exclusion of the disolder,
particularly in areas where resources for prenatal
Dop.rtment ot Otstetrlcs and Gynaecology.
Unlvsl3lty ot Hong Nong,
Tsan Yuk Hospltal, Hospltal Road,
Hong Kong
(A Ghosh
FRcoc, I\, H Y Tang MRcoG, Y H Lam MRcoG,
E Fung MRcoc); and Departnent of Mediclne,
Mary HGpltal,
Pokfulam, Hong Kong
(V Chan PhD)
Cor€Dond6nce to: Dr A Ghosh
Does the newboln baby find the nipple by
H Varendi, R H Poftet, J Winbery
We studied the
involvement of naturally occurring odours in
the baby to the nipple. One breast of each
mother was washed immediately after
delivery. The newborn
infant was
placed prone
between the
breasts. Of 30 infants, 22 spontaneously selected the
unwashed breast. The washing
had no effect on
breast temperature.
We concluded that the infants
responded to olfactory differences
between the washed and
unwashed breast6.
1994; 344: 989-90
Healdry newbom infants placed
between their mother's
locate the nipple without assistance
and typically
begin to suck within the first hour after bi-rrh.r Newbom
rats, for exampler fail to locate the oipple if their sense
smell is experimentally disrupred'? or if the modrels
ventrum is thoroughly washed.! Breastfed human infants
differentially to a gauze pad that had been
wom over dleir mother's nipple compared with an
odorised pad ftorn an unfamiliar woman, indicating that
vol 144
' Ocrcber 8, 1994 989
they recognise their mother's scent.d' Bteast odours from
lactating women are generally attractive to infantsr
regardless of their mode of feeding..t At 2 weeks of age,
babies drat had been boftle-fed since birdr spent more
time tumed toward the breast pad ftom an unfamiliat
nursing mother than in the direction of a pad treated widt
their familiar formula.s Could chemical cues associared
with the areola and nipple be implicated in initial
(unassisted) nipple localisation and sucking?' To assess
this hypothesis, nipple searching was observed after one of
the mother's breasts
had been thoroughly washed> drereby
pardy eliminating narural odou!.
36 full-term babies
bom of mothers wilhout analgesia and who
had no postpartum complications wete aecruited. 6 were
subsequently excluded
because of disrurbed
nasal breathing
or failure to respond to the mothe!'s breast during a test session
(2). The final sample was 14 girls and 16 boys (gestarionel
37-41 weeksj mean
binhweight 3676 ISD 4231
g; Apgar scores
>7 at I and 5 min).
after birth, the baby was dried, laid skin-to-skin
on rhe mother's abdomen altd covered with a blanket. An
assistent washed
one of the mother's breasts for about 15 cm
the nipple with an odou.less liquid soap: Mild$el for t5
mothels and hctacyd (Sanofi,
pH 3.5) for the remailring
The washed breast was rinsed with lukewarm weter and dried.
The right breest was
washed in 15 cases
and the left breast in the
others. Modrers were randomly assigned to the two sogps and to
the right/left sides.
After the washed breast was dried, the obsetver (unaware of
which breast had been cleaned) entered the room and moved the
baby from the mother's abdomen to the "starr" posirion-ie,
nose in the midline of the mother's chest, eyes at the level of the
Observation and recording
of the baby's behaviour
(5-13 min after birrh; mean 9.9) and continued until the
infant found
the nipple and began ro suck vigorously.
Before delivery, the mother was rold that she and the observer
would watch whether the infant could find the nipple withour
help. Mothers were instrucred not to tell the observer which
breast had
Informed consent was
obtained fiom all
mothers, and fathers when present, and the study was approved
by the locel ethics
To sludy any effecr of the washing on breast temperaruie, en
additionel 6 rnothers underwent
lbe same washing within 12
hours after delivery. Surface temperatures were recorded et the
nipple, border betwi:en the areola and white breast-skin, and
midway between rhe areola
and centre of the ches! at 5-10,
l5-20, 30-35, and 50-55 min.
25 infants spontaneously grasped a nipple and sucked
(median latency 5l min after birth [range 22-100]). The
odrer 5 requiled assistance in grasping the prolapsed
nipple; the baby had moudr contacr wirh one of rhe
nipples and repeatedly attempted to grasp it before the
observer assisted by placing rhe nipple in the infant's
mouth (median latency 54 min after birth [22-85]). None
of these 5 infants aftempted to gasp the altemative
nipple. 22 (12 boys, l0 girls) ofthe 30 infants selected the '
unwashed breast, The unwashed breast was selected by
l0 infants in the Mild$el and 12 in the Lactacyd soap
groups. The table shows median times for other early
The median temperature of washed breasts was slighdy
above that of unwashed breasts (maximum median
difference was 0'5"C).
Vithin l-2 h after birth, babies preferred their modrer's
unwashed bteast, which is consistent with studies of non-
human mammals showing dlat washing the mother's
nipplevventrum resulted in disturbed nipple finding and
feeding. \fe excluded the possibility thar our infants had
responded to differences in the warmth of dre two breasts.
min) alter birth.
Table: Early
behavlour In
30 nowborn
explain the preference
for the unwashed breast in that
the infants were responding to differences in snell.
secreting milk and colostrum,
rhe nipple/areola is
dense in glands that might secrere attractive odours. The
would have reduced o! eliminated such cues,
which is consistent
with infants orienring prefelentially
towards a gauze
pad contaminared with the breast odour
of a lactating woman compared with an odourless control
Naturally occurring matemal odoun may have a
role in guiding dre neonate ro rhe nipple, and thereby
contribute to early nipple attachment and sucking. The
causes of early failures of breasdeeding are often
unknown.' Since breasdeeding is sensitive
ro even minor
disturbances of the spontaneous interactions between
mother and baby,'o biological facton should be given
attention, Ijnnecessary routine cleaning may interfere
with the establishmenr
ofsuccessful early
breasdeedhg by
elimination of iie infant's access
ro biologically relevant
chemical signals.
This study was aided by grsnts ftom rhe Foundarion "Frimurare
BamhuseC' and fiom the Karclirst€ lnslirure.
Unwasned Washed
(n=22) breasl
Firsl handlomouth
No oi head tornings belore
choice ot side
First moutt}areola
Fnsi successiulnippl€
N0 ol sucking attempts betore success
20 (1I41t 19 (10-30)
23 (10-60) 20 t7-291
1(0-6) 2 (G6)
(1+99) 44122-72)
51(22-100) 45
(1-2r) 411-71
54122-LOO\ 4a122-73\
I Widsirttm AM, Ransjo-Arvisson AB, Chrisr€nsson K, er al. casric
suction in healthy n€wbom intun$. Acto Paediat l9a7 ; 75t 566-72.
2 Teicher MH, Flaum LE, ViUiams M, Eckhen SJ, Lumia AR. Swivll,
sowth and suckling behavior of neoniolly butbecromiz€d rats. P,lry'bi
Behao 1978i 2lt 553-61 .
3 Hofe. MA, Shair H, Sinsh P. Evidence thsr mitemal venrlal skir
promote suckling in infa rirs. Pr),'rio/aehao 1976:17.
4 Macfarlane A. Olfaction in lhe developm€nr ofsocial preferences
in the
humd neonate.
ln: Poner R, O'Connor M, €ds. Parenr-infanr
Foundation Slrnposium 33). N€w York Elsevier,
5 Schaal B, Monmgner H, Henlingq er al. Les stimulations oflactives
€ntre I'enfant et la mere. R?rrcd Nlf D@ 1980:
443 54.
6 Makn I f, Poner RH. Att"activeness of lacraring females' breast odors
to neonltes.
CirrTdDe!, 1989;60: 803-10.
7 Po(er RH, Makin J$f, Davis LB, Christensen KM. BressFfed inflnls
respond to olfactory cues fiom deir o$n moth€r a.d unfamilia.
lactatins femafes. lrldz, A.hao D@ r992t lst a5-93.
8 Poner RH, Makin IV, Dlvis LB. Chrisrensen KM. An assessm€nt of
th€ salient olfadory enimnment of formula-fed infrn6. Pb)tiol Behal)
1991, 50: 907-l l.
9 Goldman AS, Garza C. Futur€ research in hrman milk. Ped;ot Res
t 22t 493-96.
l0 Rishard I- Alad€ MO. Efrect of delivery mom routines on success
first breasFfeed. lar..r 1990;336:
Tartu Unlverslty Chlldton'6 Hospltal, Tartu, Eatonla
Varendi MD);
Isbo6tollo de
Compo.toment Anlmal, URA ll91CI{RS,/INRA,
l{ouzllly, Franco
(R H Porter
tor Womsn and
Chlld floalth, t(arollnska llo3pltal, Karolltuk ln3tltuto, Stockholh,
J Winberg MD)
Corospondonco to: Dr Heili Varendi, Tanu University Children's
Hospital, 6 Lunini
EE 2400 Tartu.
990 Vol 344
. Octobe! 8, 1994
... This recommendation was a notably novel phenomenon that emerged alongside the COVID-19 pandemic and was a point of concern for many clinicians, because it can hinder the establishment of breastfeeding. Breast washing before every feed can disrupt the neonate's ability to find the nipple by scent [9], as well as being generally burdensome to a new dyad who are both learning how to breastfeed [10]. Further, this recommendation may also disrupt the maternal skin microbiome and alter establishment of the infant's microbiome [11]. ...
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Background The COVID-19 pandemic has significantly altered how breastfeeding support is provided, resulting in mixed breastfeeding outcomes and experiences for mothers. The World Health Organization has consistently supported breastfeeding from the beginning of the pandemic. However, recommendations from obstetrical and gynaecological societies within individual countries have varied in their alignment with this guidance, resulting in inconsistent recommendations. It is unknown how breastfeeding guidelines, maternal breastfeeding experiences, and breastfeeding initiation and duration compared across five Western countries. The current study is comprised of two parts, each with a different objective. Part One objective: to review pandemic-related changes in professional society guidelines on breastfeeding support in Australia, New Zealand, Canada, the United Kingdom, and the United States; and Part Two objective: to conduct a narrative review to summarize the evidence of how the pandemic has changed breastfeeding initiation, duration, and mothers’ breastfeeding experiences during the pandemic in these five countries and provide recommendations for clinical lactation support. Methods We searched for indicators that are impactful on breastfeeding outcomes: skin-to-skin contact, rooming in, direct breastfeeding and breast washing, in the five countries mentioned above and compared these to the recommendations from the World Health Organization. Next, we conducted a narrative review of the literature from these five countries to explore how the pandemic altered breastfeeding outcomes and used this information to provide suggestions for clinical practice moving forward. Results Recommendations on the four practices above differed by country and were not always in alignment with the World Health Organization recommendations. Mother-infant separation after birth in the United States was associated with a lower prevalence of breastfeeding initiation and duration. While some mothers reported positive breastfeeding experiences during the pandemic, many mothers indicated negative experiences related to decreased social and professional support. Conclusions The pandemic can inform practice recommendations and can be viewed as an opportunity to permanently modify existing methods to support breastfeeding families. The use of virtual care increased during the pandemic and should continue with specific considerations for prioritizing in-person care. This will help to provide more timely and accessible support for breastfeeding mothers.
... Humans are born with the remarkable capacity to crawl toward their mother's breast, even though their caregivers' nurturing provides no need for self-propulsion at birth (e.g., Righard & Alade, 1990;Varendi et al., 1994;Widström et al., 1987Widström et al., , 2011). This remarkable capacity for self-propulsion is accompanied by head rooting (nipplefinding) movements (Hym et al., 2020). ...
Human newborns can propel themselves to their mother's breast when positioned skin to skin on her abdomen just after birth. For decades, researchers have considered this primitive crawling behavior a spinal reflex, immune to supra spinal control. However recent research suggest that neonatal crawling is already responsive to visual and olfactory stimuli processed at a supra spinal level. Here we report that a few hours post birth, French newborns can also modulate their crawling in response to their native language – a source of information that is processed supra‐spinally. The crawling patterns of 23 French‐born newborns were recorded on video and via an infra‐red motion capture system during two randomly ordered 2‐minute trials. The newborns were secured on a mini skateboard to facilitate arm and leg movements during their crawling propulsion. They heard a repetitive sequence of the same sentences either in French, their native language, or in English, a rhythmically different and hence discriminable unfamiliar language, on each trial. In French, compared to English, crawling was enhanced, with significantly more arm and leg steps and significantly more and larger trunk rotations in the cephalo‐caudal axis. Moreover, newborns rotated their head and trunk toward the appropriate loud speaker when hearing French but not English. These preliminary findings suggest that newborn crawling is not a simple stereotyped reflex under spinal control, but a complex pattern that can be modulated in response to higher‐order, supra‐spinally‐processed stimuli. The findings open fascinating questions about the range of stimuli to which newborn crawling is responsive. This article is protected by copyright. All rights reserved
... Dès les premiers moments de la vie, l'odeur est un repère non négligeable puisque le nouveau-né construit son arrivée au monde via l'odeur : les odeurs biologiques propres à l'environnement de l'enfant peuvent servir de marques et guider son 114 Définition du dictionnaire CNRTL : « syndrome olfacto-génital » comportement (Pihet et al., 1997). Le fait de masquer l'odeur d'un des deux seins oriente tendanciellement le choix vers le sein non lavé pour 22 bébés sur 30 (Varendi et al., 1994). De plus, on observe une activation orale plus importante face au sein odorant au détriment de cris saillants face au sein non odorant (Doucet et al., 2009). ...
Suggéré par le néologisme olf-action, l’enjeu de ma thèse est de montrer que la perception olfactive n’est pas seulement une saisie passive de notre environnement, mais un vecteur actif de nos vies à l’échelle individuelle et collective. L’odeur n’est jamais de prime abord une représentation figée, mais toujours une pratique qui s’articule par le mouvement, l’action et la transformation. A travers des tests sensoriels et des entretiens semi-directifs mêlés à des entretiens d’explicitation, mes interlocuteurs et interlocutrices, qu’ils soient à Pékin, Bombay, Rio de Janeiro, São Paulo ou Nice ne me dévoilent pas le résultat de leur perception d’odeurs, mais le cheminement de l’acte qui apparaît dès lors comme une relation présymbolique au monde. En nous penchant non plus sur l’odeur identifiable comme objet-source (ou comme rappelant l’objet-source) mais comme engagement de la vie quotidienne, nous substituons ainsi le contenu (que sens-tu ?) à l’acte olfactif (que fais-tu quand tu sens ?).
... This first phase is also postulated to be the "sensitive period" and to equally occur in most mammals (5). Newborns, placed on the mother's abdomen, can instinctively locate and suckle the maternal breast without assistance in their 1st hour of life via their sense of smell/pheromones (6)(7)(8)(9). ...
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Background: There are many studies on mother-child-bonding with little theoretical doubt that better bonding may have a positive effect on further social development. However, there is hardly any empirical evidence. In particular, there is a lack prospective longitudinal studies. Methods: As part of a longitudinal study, bonding was assessed in a community sample of 97 healthy mothers using the Postpartum Bonding Questionnaire (PBQ) 6 weeks after birth of their child. Social competencies in the offspring were assessed using the Self- and Other-oriented Social Competencies (SOCOMP) at 5.5 years of age. A potential correlation between bonding and social competencies was tested using Spearman Rank Correlation. Results: Retention rate over 5.5 years was 77.23%. Lower Maternal Bonding Impairment Scores 6 weeks postnatally were positively related to childrens' social competences at 5.5 years of age. Conclusion: The present data confirm a positive and long-term influence of bonding on social skills and provide further evidence of the importance of parent child bonding for child development in general. This result should give reason to further investigate this relationship in depth, causally and at later points in time.
... Zmysły węchu i smaku również odgrywają rolę w interakcjach dzieckorodzic, szczególnie w najwcześniejszym okresie życia (Corona, Lévy, 2015;Nishitani i in., 2009;Varendi, Porter, Winberg, 1994). Jednak ze względu na bardzo ograniczoną możliwość regulowania własnego zapachu w celu kształtowania przebiegu interakcji, zagadnienia te nie będą tutaj poruszane. ...
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Książka przedstawia analizę interakcji dziecko–rodzic – narzędzie stosowane przez psychologów w procesie diagnozy oraz w badaniach naukowych. Celem książki jest dostarczenie Czytelnikowi podstawowych informacji teoretycznych i praktycznych, przygotowujących do używania analizy interakcji w praktyce klinicznej i w badaniach. Pierwsza część książki wprowadza w zagadnienie i przedstawia kolejne kroki analizy interakcji dziecko–rodzic oraz schematy oceny interakcji stosowane w badaniach naukowych. Druga część książki opisuje rozwój kompetencji interakcyjnych niemowlęcia oraz zawiera przegląd wyników badań nad interakcjami dziecko–rodzic w grupach dzieci z wybranymi zaburzeniami rozwoju.
... The initial nipple localization and sucking of a human infant are guided by the mother's breast odor. Newborns tend to crawl to the odor source and preferentially suck from an untreated breast rather than one whose natural odor is eliminated by washing (Varendi et al., 1994;Varendi and Porter, 2001), which represents the strongest case to date for a releaser effect in humans. Chemosensory studies on adult men and women have largely focused on the axillae. ...
Pheromones are chemicals that serve communicational purposes within a species. In most terrestrial mammals, pheromones are detected by either the olfactory epithelium or the vomeronasal organ and processed by various downstream structures including the medial amygdala and the hypothalamus to regulate motivated behaviors and endocrine responses. The search for human pheromones began in the 1970s. Whereas bioactive ligands are yet to be identified, there has been accumulating evidence that human body odors exert a range of pheromone-like effects on the recipients, including triggering innate behavioral responses, modulating endocrine levels, signaling social information, and affecting mood and cognition. In parallel, results from recent brain imaging studies suggest that body odors evoke distinct neural responses from those observed with common nonsocial odors. Two endogenous steroids androsta-4,16,- dien-3-one and estra-1,3,5(10),16-tetraen-3-ol are considered by some as candidates for human sex pheromones. The two substances produce sexually dimorphic effects on human perception, mood, and physiological arousal. Moreover, they reportedly elicit different hypothalamic response patterns in manners contingent on the recipients’ sex and sexual orientation. Neuroendocrine mechanisms underlying the effects of human chemosignals are not yet clear and await future detailed analyses.
Touch plays an important role in the development of infants and children. In this review, we highlight the neural conditioning of affective touch and the related physiological responses, especially in the form of parasympathetic activation, pain suppression and stress relief. Based on recent studies, we show that the functionality of a population of C-tactile (CT) nerve fibers, hypothesized to provide the neurobiological substrate for the transmission of interpersonal touch, is already mature in the newborn and that the developmentally beneficial effects of such touch are already evident at this stage. We further aim to shed light on the role of nurturing touch in stimulating CT fibers. Based on this, we hypothesize that CT stimulation acts as a reinforcer that contributes to the development of newborns into social beings by means of conditioning.
Two-week-old breast-feeding infants were tested for their responses to alfactory cues produced by nursing mothers. Mean durations of orientation in the direction of a breast pad worn by an unfamiliar lactating female were greater than towards either a clean control pad or an axillary pad from the same stimulus female. When tested with odor pads worn by their own mother, however, infants did not orient differentially to her breast versus axillary odors. Breast odors from nursing females appear to be generally attactive to neonates. Moreover, breast-fed infants are capable of recognizing their own mother through the scent of her breast or axillary secretions, and are attracted to both of these sources of her unique alfactory signature.
Washing a lactating rat's ventral skin with acetone, alcohol and water markedly reduces the effectiveness with which her 2-week-old infants can initiate suckling on the anesthetized mother. Control experiments with detailed thermal and behavioral measures give evidence tending to rule out lowered skin temperature, altered thermal gradients, changed tactile characteristics of abdominal fur or nipples and aversion to remaining traces of the organic solvents as responsible for the infants' failure to find and attach to nipples. The data suggest that some substance(s) on the skin of the mother's ventrum act as olfactory and/or gustatory cues for the infants' orientation and attachment to nipples.
The importance of the olfactory bulbs in the neonatal rats ability to suckle, and hence survive and grow, was evaluated using modified surgical and post-operative rearing conditions. More than 90% of two-day-old bilaterally bulbectomized pups survived surgery and recovered sufficiently to gain weight and grow at near-normal rates. However, these pups were markedly deficient in their ability to locate and attach to their anesthetized mothers' nipples. They did however, manage to attach when held in direct contact with these nipples. As expected, washing olfactory cues for suckling from the nipple surface with methylene chloride-ethanol severely disrupted the suckling behavior of their normal and unilaterally bulbectomized littermates. Removing these cues had no effect on the attachment behavior of bilaterally bulbectomized pups, demonstrating that neonatal rats possess sufficient behavioral plasticity to utilize other cues for suckling in the absence of olfaction.
Olfactory preferences of two-week-old bottle-fed infants were assessed in a series of simultaneous two-choice tests. Infants of each sex displayed preferential orientation to a stimulus pad worn on their mother's breast over a clean control pad. When maternal breast odor was paired with the odor of the infants' formula, however, boys spent more time oriented toward the formula odor, whereas girls evinced no reliable preferences. Although the subject infants had no prior direct contact with odors emanating from the breasts of lactating females, but had recurring reinforced exposure to the odor of their familiar formula (in the context of feeding), the former scents elicited a more positive response. Preferential orientation to lactating-breast odors reflects adaptive inborn attraction to cues associated with the natural food source for human neonates.
72 infants delivered normally were observed for 2 h after birth. In the separation group (n = 34), the infant was placed on the mother's abdomen immediately after birth but removed after about 20 min for measuring and dressing. In the contact group (n = 38) contact between mother and infant was uninterrupted for at least 1 h. After about 20 min the infants began to make crawling movements towards the breast; the rooting reflex soon came into play, and at an average of 50 min after birth most of the infants were sucking at the breast. More infants in the contact group than in the separation group showed the correct sucking technique (24/38 vs 7/34). 40 (56%) of the 72 mothers had received pethidine during labour; the infants were also sedated and most of them (25/40) did not suck at all. It is suggested that contact between mother and infant should be uninterrupted during the first hour after birth or until the first breast-feed has been accomplished, and that use of drugs such as pethidine should be restricted.
A series of experiments investigated the responses of human infants to olfactory cues produced by lactating females. 2-week-old bottle-feeding girls oriented preferentially to the breast odor (odorized pad) of a nursing woman when paired with such odors from either a nonparturient female or axillary odors from the same lactating female. Responses to axillary odor from a lactating female did not differ from those to a clean (nonodorized) pad. These data indicate that breast odors from lactating females are especially attractive to female infants who are unfamiliar with the stimulus woman and who have had no prior breast-feeding experience.
Because of the importance of breast-feeding to child health, research in the formation, composition, and biological effects of human milk should be strongly encouraged. Future exploration should include the processes that are responsible for the synthesis and secretion of human milk; the nature and function of the physical compartments in human milk; the structure and function of certain proteins and other components in human milk; and the in vivo fate and effect of a host of constituents including nutrients, growth factors, hormones, inducers, immunological factors, and antiinflammatory agents. Because of the potential public health benefits, these studies should be a high priority in pediatric research for the next decade.
Gastric emptying of newborn infants is a procedure performed to prevent aspiration of gastric contents. The present investigation was conducted to study the effects of gastric suction on circulatory and behavioural parameters in 21 healthy newborn children (11 cases, 10 controls). A small elevation in mean arterial blood pressure was observed during gastric suction. The incidence of retching was also increased. In all children spontaneous sucking and rooting movements, as well as state of sleep and wakefulness were recorded. In the control group spontaneous sucking and rooting movements started occur 15 min after birth and reached a maximum at 45 and 60 min, respectively. The first hand to mouth movement was observed after a mean of 34 min and the infants found the nipple and started to suckle at about 55 min. This sequence of prefeeding behaviour was disrupted in children who had undergone gastric suction. The physiological side-effects induced by gastric suction are minor, but it seemed to be unpleasant for the child and no clear advantages are gained by the procedure.