2. 272 ABM PROTOCOLS
separation of mother and baby after birth may greater incidence and duration of neonatal
lead to higher risks of difficulty with breast- depression, cyanosis, and bradycardia.
feeding initiation.3–5 Labor pain management 3. Nalbuphine, butorphanol, and pentazocine
strategies may affect these labor outcomes and may be used for patients with certain opioid
secondarily affect breastfeeding initiation in allergies or at increased risk of difficult air-
addition to any direct effects of the medications way management or respiratory depression.
themselves.6 However, these medications may interfere
Women have differing levels of pain toler- with fetal heart rate monitoring interpreta-
ance. Pain that exceeds a woman’s ability to tion. Observe the mother and infant for psy-
cope, or pain magnified by fear and anxiety, chotomimetic reactions (3%).
may produce suffering in labor. Suffering in la- 4. Multiple doses of intravenous analgesic, and
bor may lead to dysfunctional labors, poorer their timing of administration may lead to
psychologic outcomes, and increased risk of greater neonatal effects. For example, fen-
postpartum depression, all of which may have tanyl administration within 1 hour of deliv-
a negative effect on breastfeeding.7 ery or meperidine administration between 1
Continuous support in labor, ideally by a and 4 hours before delivery is associated
trained doula, reduces the need for pharmaco- with more profound neonatal effects.
logic pain management in labor, decreases in- 5. When a mother has received intravenous
strumented delivery and Cesarean section, and narcotics for labor, mother and baby should
leads to improved breastfeeding outcomes be given more skin-to-skin time to encour-
both in the immediate postpartum period and age early breastfeeding.14
several weeks after birth.8
Nonpharmacologic methods for pain man- There is little evidence regarding the effects
agement in labor such as hypnosis, psy- of epidural analgesia on breastfeeding and the
choprophylaxis (e.g., Lamaze), intradermal or available data are inconclusive. Early studies of
subcutaneous water injections for back pain, epidural analgesia for labor showed neonatal
and so on, appear to be safe, have no known neurobehavioral effects and labor effects that
adverse neonatal effects, and may reduce the may have had a significant impact on breast-
need for pharmacologic pain management. feeding. The few studies that have looked di-
More study of breastfeeding outcomes is rectly at breastfeeding outcomes have sug-
needed for these modalities.9,10 gested poorer outcomes in women who had
Evidence suggests that breastfeeding success epidural analgesia.15–18 These results must be
is affected by the behavior of the newborn. De- interpreted with caution, however, as most of
pressed or delayed suckling, which can be these studies have been problematic with poor
caused by medications given to mothers, can control groups and much crossover between
lead to delayed or suppressed lactogenesis and study groups. Furthermore, it is difficult to as-
risk of excess infant weight loss.11,12 certain whether the effects were caused by the
Intravenous opiates for labor may block the epidural per se, or epidural use was a marker
newborn’s normal reflexes to seek the breast, for abnormal labor with adverse effects not di-
root, and suckle within the first hour after rectly attributable to the epidural. Epidural
birth.13,14 analgesia also may affect labor outcomes, for
example, increasing instrumented delivery,
1. Shorter-acting opiates such as fentanyl are which may secondarily affect breastfeeding
preferred. Remifentanil is potent and has outcomes.4,5 One study has suggested that
rapid onset and offset but can be associated when epidural analgesia is commonplace in a
with a high incidence of maternal apnea, re- hospital supportive of breastfeeding, longer-
quiring increased monitoring. Its transfer in term breastfeeding outcomes are not adversely
utero to the fetus is minimal. affected by epidural analgesia.19 A recent ran-
2. Meperidine/pethidine generally should not domized, double-blind study showed that
be used except in small doses less than 1 epidural analgesia with fentanyl in low-to-
hour before anticipated delivery because of moderate doses, along with bupivacaine, did
3. ABM PROTOCOLS 273
not have any effect on breastfeeding outcomes for labor. However, their use is limited by sev-
compared to epidural analgesia using bupiva- eral factors, including lack of efficacy, techni-
caine alone. Higher doses of fentanyl ( 150 g cal difficulties, and a high rate of complications.
total dose) may have had a small negative ef-
fect on maternal perception of breastfeeding at
24 hours and breastfeeding continuation at 6 ANESTHESIA FOR CESAREAN SECTION
weeks.20
Regional anesthesia (epidural or intrathe-
1. If epidural anesthesia is chosen, methods cal/spinal) is preferred over general anesthe-
that minimize the dose of medication and sia.26,27
minimize motor block should be used. Separation of the mother and baby should be
Longer durations of epidural analgesia minimized and breastfeeding initiated as soon
should be avoided if possible,21 and admin- as feasible. In fact, the baby may go to the breast
istration should be delayed until necessary in the operating room during abdominal clo-
to minimize effect on labor outcomes that sure with assistance to support the infant on
may secondarily affect breastfeeding. Com- the mother’s chest. If breastfeeding is initiated
bined spinal-epidural analgesia and patient- in the recovery room, there is the added ad-
controlled epidural analgesia may be prefer- vantage that the incision is often still under the
able. influence of the anesthetic.
2. Infants lose more weight in the first post- A mother may breastfeed postoperatively as
partum days when labor medications are soon as she is alert enough to hold the baby.
used.12 Some of this weight loss may be a
result of mothers receiving an intravenous
(IV) fluid load for epidural analgesia. One POSTPARTUM ANESTHESIA
report notes babies are slightly heavier on
average and lose more weight in the first Nonopioid analgesics
days postpartum when epidural analgesia is Nonopioid analgesics generally should be
used.22 In addition, the use of large volumes the first choice for pain management in breast-
of intrapartum IV fluids has been associated feeding postpartum women, as they do not im-
with a decrease in plasma oncotic pres- pact maternal or infant alertness.
sure,23 which may then increase breast en-
gorgement and interfere with subsequent 1. Acetaminophen and ibuprofen are safe and
milk production and/or transfer. Conserva- effective for analgesia in postpartum moth-
tive use of fluids may mitigate this effect. ers.
Definitive studies of these interrelationships 2. Parenteral ketorolac may be used in moth-
are needed in order to better assess first- ers not subject to hemorrhage, and with no
week weight loss in individual newborns. history of gastritis, aspirin allergy, or renal
3. When epidural analgesia has been used for insufficiency.
labor, particular care to provide mothers 3. Diclofenac suppositories are available in
with good breastfeeding support and close some countries and commonly used for
follow-up after postpartum hospitalization postpartum analgesia. Milk levels are ex-
should be taken. tremely low.
4. Cox-2 inhibitors such as celecoxib may have
There are minimal data concerning the pedi- some theoretic advantages if maternal
atric effects of other labor anesthesia, including bleeding is a concern. This must be balanced
inhaled nitrous oxide, paracervical block, pu- with higher cost and possible cardiovascu-
dendal block, and local perineal anesthesia.24,25 lar risks, which should be minimal with
These modalities do not usually expose the in- short-term use in healthy young women.
fant to significant quantities of medication. In
some situations, these may serve as alternatives Both pain and opioid analgesia can have a
to intravenous narcotics or epidural analgesia negative impact on breastfeeding outcomes;
4. 274 ABM PROTOCOLS
thus, mothers should be encouraged to control use may lead to some sedation in the in-
their pain with the lowest medication dose that fant.
is fully effective. Opioid analgesia postpartum
may affect babies’ alertness and suckling vigor. Epidural/spinal medications
However, when maternal pain is adequately
1. Single-dose opioid medications (e.g., neu-
treated, breastfeeding outcomes improve.28 Es-
raxial morphine) should have minimal ef-
pecially after Cesarean birth or severe perineal
fects on breastfeeding because of negligible
trauma requiring repair, mothers should be en-
maternal plasma levels achieved. Extremely
couraged to adequately control their pain.
low doses of morphine are effective.
2. Continuous post-Cesarean epidural infu-
Intravenous medications
sion may be an effective form of pain relief
1. Meperidine should be avoided because of that minimizes opioid exposure. A random-
reported neonatal sedation when given to ized study that compared spinal anesthesia
breastfeeding mothers postpartum,29 in ad- for elective Cesarean with or without the use
dition to the concerns of cyanosis, brady- of postoperative extradural continuous
cardia, and risk of apnea, which have been bupivacaine found that the continuous
noted with intrapartum administration.30,31 group had lower pain scores and a higher
2. The administration of moderate to low doses volume of milk fed to their infants.35
of IV or IM morphine is preferred as its pas-
sage to milk and oral bioavailability in the
infant are least with this agent.29,32 ANESTHESIA FOR SURGERY IN
3. When patient-controlled IV analgesia (PCA) BREASTFEEDING MOTHERS
is chosen after Cesarean section, morphine
The implications of drugs used in anesthesia
or fentanyl is preferred to meperidine.33
in postpartum mothers depends on numerous
4. Although there are no data on the transfer of
factors, including the age of the infant, stabil-
nalbuphine, butorphanol, and pentazocine
ity of the infant, stage of lactation (early or late
into milk, there have been numerous anecdo-
stage), and ability of the infant to handle the
tal reports of a psychotomimetic effect when
clearance of small quantities of anesthetic med-
these agents are used in labor. They may be
ications.36 Anesthetic agents will have little or
suitable in individuals with certain opioid al-
no effect on older infants, but could cause prob-
lergies or other conditions described in the
lems in newborn infants, particularly those
preceding section on labor (see page 272 #3).
who are premature or suffer from apnea.
5. Hydromorphone (approximately 7 to 11
The ability of the infant to clear small
times as potent as morphine), is sometimes
amounts of these medications is of primary
used for extreme pain in a PCA, IM, IV, or
concern before returning to breastfeeding. In-
orally. Following a 2-mg intranasal dose,
fants subject to apnea, hypotension, or weak-
levels in milk were quite low with a relative
ness probably should be protected by a few
infant dose of about 0.67%.34 This correlates
more hours of interruption from breastfeeding
with about 2.2 g/day via milk. This dose
before resuming (12 to 24 h) nursing.
is probably too low to affect a breastfeeding
Mothers with normal term or older infants
infant, but this is a strong opioid and some
generally can resume breastfeeding as soon as
caution is recommended.
they are awake, stable, and alert. Resumption
of normal mentation is a hallmark that these
Oral medications
medications have left the plasma compartment
1. Hydrocodone and codeine have been used (and thus the milk compartment) and entered
worldwide in millions of breastfeeding adipose and muscle tissue where they are
mothers. This suggests they are suitable slowly released. A single pumping and dis-
choices even though there are no data re- carding of the mother’s milk following surgery
porting their transfer into milk. Higher will significantly eliminate any drug retained
doses (10 mg hydrocodone) and frequent in milk fat, although this is seldom necessary
5. ABM PROTOCOLS 275
and not generally recommended. For women its limited transport to milk, and poor oral
who undergo postpartum tubal ligation, bioavailability in infants.29,33
breastfeeding interruption is not indicated, as 2. The transfer of meperidine into breast milk
the volume of colostrum is small.37 In addition, is documented, although it is somewhat low
the levels of medication in the maternal plasma (1.7% to 3.5% of maternal dose). However,
and milk are low once mothers resume normal the administration of meperidine and its me-
mentation. Regional anesthesia is recom- tabolite (normeperidine) is consistently as-
mended for this procedure in preference to sociated with neonatal sedation, which is
general anesthetic for maternal safety. dose related. Transfer into milk and neona-
Mothers who have undergone dental extrac- tal sedation have been documented for up
tions or other procedures requiring the use of to 36 hours after the dose.29 Meperidine
single doses of medication for sedation and should be avoided during labor and in post-
analgesia can breastfeed as soon as they are partum analgesia (except, perhaps, within 1
awake and stable. Although shorter-acting hour before delivery). Infants of mothers
agents such as fentanyl and midazolam may be who have been exposed to repeated doses
preferred, single doses of meperidine or di- of meperidine should be closely monitored
azepam are unlikely to affect the breastfeeding for sedation, cyanosis, bradycardia, and pos-
infant.36 sibly seizures.
Mothers who have undergone plastic sur- 2. Although there are no published data on
gery, such as liposuction, in which large doses remifentanil, this esterase-metabolized opi-
of local anesthetics (lidocaine) have been used oid has a brief half-life even in infants ( 10
probably should pump and discard their milk minutes) and has been documented to pro-
for 12 hours before resuming breastfeeding. duce no fetal sedation even in utero. Al-
though its duration of action is limited, it
could be used safely, and indeed may be
SPECIFIC AGENTS USED FOR ideal in breastfeeding mothers for short
ANESTHESIA AND ANALGESIA painful procedures.
3. Fentanyl levels in breast milk have been
Anesthetics studied and are extremely low to below the
limit of detection.42,43
Drugs used for induction such as propofol,
4. Sufentanil transfer into milk has not been
midazolam, etomidate, or thiopental enter the
published, but it should be similar to fen-
milk compartment only minimally, as they
tanyl.
have extraordinarily brief plasma distribution
5. Nalbuphine, butorphanol, and penta-
phases (only minutes) and hence their trans-
zocine levels in breast milk have not been
port to milk is low to nil.38–41
published. At this time they would only
Little or nothing has been reported about the
be indicated in the specific situations
use of anesthetic gases in breastfeeding moth-
mentioned previously (see page 272 #3). If
ers. However, they too have brief plasma dis-
these agents are used, observe the mother
tribution phases and milk levels are likely nil.
and infant for psychotomimetic reactions
The use of ketamine in breastfeeding moth-
(3%).
ers is unreported. Because of its high rate of
6. Hydrocodone and codeine have been used
psychotomimetic effect, including hallucina-
in millions of breastfeeding mothers. Oc-
tions and dissociative anesthesia (catalepsy,
casional cases of neonatal sedation have
nystagmus), ketamine is probably not an ideal
been documented, but these are rare and
anesthetic agent for breastfeeding mothers.
generally dose related. Doses in breast-
feeding mothers should be kept at the min-
Analgesics
imum necessary to control pain. Routine,
Opioid analgesics. consistent dosing throughout the day may
1. Morphine is still considered an ideal anal- lead to sedative effects in the breastfed in-
gesic for breastfeeding mothers because of fant.
6. 276 ABM PROTOCOLS
NSAID analgesics. 3. Rajan L. The impact of obstetric procedures and anal-
1. Ibuprofen is considered an ideal, moder- gesia/anaesthesia during labour and delivery on
breast feeding. Midwifery 1994;10:87–103.
ately effective analgesic. Its transfer to milk
4. Tamminen T, Verronen P, Saarikoski S, et al. The in-
is low to nil.44,45 fluence of perinatal factors on breast feeding. Acta
2. Ketorolac is considered an ideal and potent Paediatr Scand 1983;72:9–12.
analgesic in breastfeeding mothers. The 5. Patel RR, Liegling RE, Murphy DJ. Effect of operative
transfer of ketorolac into milk is extremely delivery in the second stage of labor on breastfeeding
low.46 However, its use in patients with success. Birth 2003;30:255–260.
6. Howell CJ. Epidural versus non-epidural analgesia
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function. Other contraindications are noted 2006(4):CD003521.
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3. Celecoxib transfer into milk is extraordinar- Am J Obstet Gynecol 2005;192:826–831.
8. Hodnett ED, Gates S, Hofmeyr GJ, et al. Continuous
ily low ( 0.3% of the maternal dose).47 Its
support for women during childbirth. Cochrane Re-
short-term use is safe. views 2003;3:CD003766.
4. Naproxen transfer into milk is low, but gas- 9. Simkin PP, O’Hara MA. Nonpharmacologic relief of
trointestinal disturbances have been reported pain during labor: Systematic reviews of five meth-
in some infants after prolonged therapy. ods. Am J Obstet Gynecol 2002;186:S131–159.
Short-term use (1 week) probably is safe.48,49 10. Smith CA, Collins CT, Cyna AM, et al. Complemen-
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11. Mizuno K, Fujimaki K, Sawada M. Sucking behavior
RECOMMENDATIONS FOR at breast during the early newborn period affects later
FUTURE RESEARCH breast-feeding rate and duration of breast-feeding. Pe-
diatr Intl 2004;46:15–20.
Studies of labor analgesia and labor anes- 12. Dewey KG, Nommsen-Rivers LA, Heinig MJ, et al.
thesia should specifically study breastfeeding Risk factors for suboptimal infant breastfeeding be-
havior, delayed onset of lactation, and excess neona-
outcomes.
tal weight loss. Pediatrics 2003;112:607–618.
Specific data is needed about the use of in- 13. Ransjo-Arvidson AB, Matthiesen, SA, Lilja G, et al.
travenous fluid loading during labor, such as Maternal analgesia during labor disturbs newborn be-
for epidural anesthesia, and its effects on infant havior: Effects on breastfeeding, temperature, and
birthweight, breast engorgement, milk supply, crying. Birth 2001;28:5–12.
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bupivacaine after cesarean section on the amount of Protocol Committee
breast feeding and infant weight gain. Anesthesiol Caroline J. Chantry, M.D., Co-Chairperson
Analg 1996;82:1166–1169. Cynthia R. Howard, M.D., MPH,
36. Hale TW. Anesthetic medications in breastfeeding
Co-Chairperson
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37. Rathmell JP, Viscomi CM, Ashburn MA. Management Ruth A. Lawrence, M.D.
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38. Andersen LW, Qvist T, Hertz J, et al. Concentrations For reprint requests: abm@bfmed.org