Induced Lactation and
Relactation (Including Nursing an Adopted Baby) and
Cross-Nursing
As breastfeeding has returned to being the pre- ferred form of nourishment for the infant, there has been an increased interest in induced lactation.
Induced lactation is the process by which a non- puerperal woman is stimulated to lactate—in other words, breastfeeding without pregnancy. Relacta- tion is the process by which a woman who has given birth but did not initially breastfeed is stim- ulated to lactate. This may also apply to a mother who may have initially breastfed her infant, weaned the infant, and then chooses to reinstitute lactation.
Relactation can also involve a woman who previ- ously breastfed a biologic child, even years before, and now is adopting a newborn. There are no blinded controlled research studies about either induced lactation or relactation. There are occa- sional observation reports about successes in a small series of dyads. The process has not been confirmed by clinical trials.41The literature is actually meager and predominantly in the animal research field.
Historical Perspective
Induced lactation and relactation are not new con- cepts but rather are well known to history and to other cultures. The motivation historically has been to provide nourishment for an infant whose mother has died in childbirth or is unable to nurse for some
reason. A friend or relative would take on the care of the child and with it the responsibility to nourish the infant at the breast because no other alterna- tives were available.
Relactation has been used in times of disaster or epidemics to provide safe nutrition to weaned or motherless infants. Numerous historical accounts of induced lactation are recorded in the medical lit- erature and reviewed in the writings of Brown.8 Mead27recorded the occurrence of relactation in her writings about New Guinea in 1935. Other anthropologists have made similar observations in other preindustrialized societies of women who have not borne children and, after a few weeks of placing the suckling infant to the breast, produce milk adequate to nourish the infant.36 Until recently, Western world literature reported the phenomenon as an anecdotal report as part of the discussion of aberrant lactation. In 1971, Cohen13 reported a patient who had been nursing an adopted child successfully for weeks when first seen in his pediatric office.
Today, the interest in induced lactation in the industrialized world stems from a desire on the part of adopting mothers to nurture an adopted child at the breast even though they were unable to carry the infant in utero. The interest in relactation comes from mothers of sick or premature infants who want to breastfeed their infants after the days 667
and weeks of neonatal intensive care are over.
These mothers, although postpartum, have not been lactating.
Induced Versus Inappropriate Lactation
The process of induced lactation is separate from galactorrhea, or inappropriate lactation, which has been described in the medical literature for more than 100 years.44 Abnormal lactation has been observed in a number of circumstances in nul- liparous and parous women and even in men. There are many eponyms for these conditions, usually based on the name of the physician who first described the syndrome, such as Chiari-Frommel and Ahumada-del Castillo.
Normally in the absence of suckling, lactation ceases 14 to 21 days after delivery. Milk flow that continues 3 to 6 months after abortion or any ter- mination of pregnancy is termedabnormalorinappro- priate lactation, or galactorrhea. Galactorrhea also refers to lactation in a woman 3 months after wean- ing or the secretion of milk in a nulliparous woman in association with hyperprolactinemia and amen- orrhea. Although these cases are pathologic in nature and, therefore, different from the groups under discussion, it is noteworthy that some knowl- edge of the initiation and maintenance of lactation has been gained from the study of these syndromes.
A nonpregnant woman who develops spontaneous lactation should be evaluated for hormonal disease.
The most common cause is a prolactinoma of the pituitary. Spontaneous lactation should not be ignored.
Animal Studies
Information on the incidence of nonoffspring nurs- ing in 100 mammalian species has been assembled by Packer et al.32 The incidence of nonoffspring nursing is increased by captivity. It is more com- mon in species with large litters (polytocous taxa) and differs from that which occurs with single young species (monotocous taxa). In the latter, it is more common for females to continue nursing after they have lost their own young. Among non- domesticated animals, spontaneous lactation has been observed repeatedly only in the dwarf mon- goose (Helogale parvula).
Lactation has been induced for scientific and commercial purposes in nonpregnant and nonpar- turient animals by the continual systematic applica- tion of a mechanical milking apparatus to the mammary gland of the animal.25 The response is
effected through the release of a mammotropic hor- mone from the anterior pituitary gland. This effect is abolished if the pituitary stalk is transected.
Ruminants respond to the addition of estrogen or estrogen-progesterone combinations, which facili- tate mammary growth. Experiments in goats involved applying ointment containing estradiol benzoate to the udders of virgins, which resulted in development of the udder and milk yield almost comparable to normal postpartum animals.14It was subsequently shown, however, that a combination of estrogen-progesterone not only resulted in bet- ter milk yield, but histologically the lobuloalveolar growth was normal, whereas with estrogen alone growth was cystic and irregular. It was also demon- strated that ovariectomized goats could be stimu- lated to lactate with these two hormones, with resultant normal histology of the udder and good milk production. Initiation of regular milkings had a significant impact on production of milk.
Because lactation can be stimulated when the ovaries have been removed but not when the pitu- itary stalk has been severed, this has significance for understanding some of the postpartum lactation failures in women. Again in ruminants, growth hor- mone and thyroid hormone have been shown to increase milk yield, although prolactin does not.
This suggests that prolactin is not deficient in rumi- nants. Because the motivation, goals, and physio- logic problems may be slightly different, induced lactation and relactation in women are discussed separately.
Induced Lactation
When a mother chooses to nurse her adopted infant, the goal is usually to achieve a mother-infant relationship that may also have the benefit of some nutrition. In that perspective, success can be evalu- ated on the basis of whether an infant will suckle the breast and achieve some comfort and security from this opportunity and close relationship with the new mother. As has been well described by Avery,5this is nurturing with the emphasis on nur- turing, not on “breastfeeding” or nutrition. A mother who is interested in inducing lactation to nurse an adopted infant may need to understand that she may never be able to sustain the infant completely by her milk alone without supplemen- tation. Neither the physician nor the mother should be disappointed. The nurturing goal is still achieved. An adoptive mother induced lactation for premature twins who were exclusively breastfed by 2 months of age. The mother succeeded due to careful planning and support of the health care team.38
PREPARATION OF THE BREAST
Normally the breast is prepared by the proliferation of the ductal and alveolar system throughout preg- nancy in anticipation of the time when lactation will begin, when the infant delivers and the pla- centa is removed.24Thus it is appropriate to assume that a period of similar preparation should take place in induced lactation. It has been suggested that a woman should begin systematically to express the breasts manually and stimulate the nip- ples for up to 2 months before the arrival of the infant, if time permits. A hand pump or other pump- ing devices can be used, but manual expression may work as well or better. Sometimes some secretion can be produced in this manner if it is carried out systematically on a uniform schedule throughout the day. The schedule should be practical, that is, include times when a mother could take a moment for this activity, such as morning and night plus any times she uses the bathroom or can conveniently handle her breasts.
A more aggressive approach involves hormones and medications. During pregnancy, the breasts are prepared by the hormones generated by the preg- nancy, estrogen, progesterone, and human placen- tal lactogen (seeFigure 3-2).
To mimic this environment, it has been suggested that starting a course of estrogen and progesterone would be appropriate, namely, prescribing oral con- traceptive dosing that suppresses ovulation (such as Ortho-Novum). This dosing should be maintained without a pause as it would be during pregnancy.30 Unfortunately, women who are adopting typically do not have 9 months to prepare, so priming the breasts with hormones may not be possible because the hormones need to be discontinued a month before anticipated lactation.
Concomitant with hormone therapy should be breast stimulation with systematic pumping with a good electric double pump. Timing should begin gradually, 5 minutes three times per day, then 10 minutes, increasing to every 4 hours. Pumping about the same time every day is helpful. It usually takes about a month before drops of milk appear.
This is a good time to start domperidone (not avail- able in the United States).2The schedule adopted by Newman29in Canada is 10 mg three times per day, increasing during a month’s time to 20 mg four times per day. Newman suggests using domperi- done from the beginning.29 Without a placenta, the adoptive mother does not have “prolactin inhib- iting” hormone to block the breast from responding to the prolactin secreted because of the breast stim- ulation. When domperidone is initiated, milk should appear in increasing quantities. Many women have achieved success by pumping alone initially and then adding galactagogues.
In other cultures in which lactation is induced as a survival tactic for the infant, no period of prepa- ration is available. An infant is put to the adoptive mother’s breast and allowed to suckle. Emphasis has been placed on herbal teas as galactagogues and good nourishment for the mother, and the infant is also given prechewed food, gruel, or animal milk.
Mead27attributed much of the success of induced lactation to the ingestion of ample supplies of coco- nut milk by the new mother. Coconuts are well known in herbal medicine; the oil pressed from ripe fruit is used for wound healing and inflammation.34 Adoption is not an easy process, and, in fact, it can be quite stressful to become an instant parent. In assisting such a mother, consideration should be given to the infant’s age, previous feeding experi- ence, and any medical problems that may exist.
Provision for additional nourishment during the process of establishing some milk secretion is most important. Onset of lactation varies from 1 to 6 weeks, averaging about 4 weeks after initiation of stimulation with the appearance of the first drops of milk. When the infant is actually nursing at the breast and being nourished by supplements, milk may appear as early as 1 to 2 weeks.
Some infants are easily confused by switching back and forth between breast and bottle because the sucking technique is slightly different. Other nourishment can be offered by dropper, by small medicine cup, or as solid foods. A unique system is available, however, for providing nourishment for the infant while suckling at the breast. It involves the use of a device to provide a source of nourishment while the infant suckles at the breast, thus stimulating production. It is further described later in this chapter and is called the Lact-Aid Nursing Trainer System (Lact-Aid Inter- national Inc., Athens, Tennessee) or Supplemental Nursing System (Medela Inc., McHenry, Illinois).
OTHER DRUG SCHEDULES TO INDUCE LACTATION
As described inChapter 3, estrogen and progeste- rone stimulate the proliferation of the alveolar and ductal systems. These hormones work in associa- tion with an increase in prolactin production.
Although the prolactin level is high during preg- nancy, milk secretion is inhibited by the presence of the estrogen, progesterone, and placental lacto- gen, the prolactin inhibiting hormone. After deliv- ery has occurred and the placenta is removed, these hormone levels fall, and prolactin initiates milk pro- duction. Efforts to stimulate this hormonal response have had variable success and are not usually recommended because of the possible effect on an infant through the milk. Women taking oral
contraceptives have been noted in some cases to have breast enlargement. In addition, although estrogen and progesterone may enhance prolifera- tion, they may inhibit lactation per se, so they must be discontinued well before lactation is planned to begin.
The dosage of conjugated estrogens recom- mended by Waletzky and Herman47 is 2.5 mg twice per day for 14 days beginning on the fourth day of a regular menstrual cycle. Giving 0.35 mg norethindrone once daily for the morning dose of estrogen prevents breakthrough bleeding. Medica- tion is given for 2 weeks and is comparable in dos- age to 2 weeks of oral contraceptives. This therapy may be accompanied by some side effects. The reg- imen should include direct efforts to stimulate lac- tation by pumping the breasts.
A report from Papua New Guinea, where induc- ing lactation is critical to adequate infant nutrition, recommends priming the breast tissue of nullipa- rous women or those who have not lactated with 50 mcg ethinyl estradiol three times per day for a week.21Medroxyprogesterone (Depo-Provera) has been used to initiate lactation in nonpuerperal women. A dose of 100 mg is given intramuscularly a week before stimulating the breast with massage and pumping. Galactagogues, such as metoclopra- mide, domperidone, or herbals, can be introduced.
This approach was reported in Papua New Guinea, and success was claimed in 24 of 27 women.28When relactation is the goal in women who have previ- ously lactated, pumping and massaging alone are initiated.
Growth hormone and prolactin have consider- able genetic similarity, as reflected in some overlap of function.12High concentrations of growth hor- mone can cause lobuloalveolar development and casein expression. Growth hormone may play a role in optimization of milk production during lac- tation and even an accessory role in the induction of lactogenesis. Both natural and recombinant human growth hormones are potent inductors of milk synthesis in pregnant and lactating rats. This effect is attributed to their effect on the prolactin receptor.12
Oxytocin is a critical component in the milk- ejection reflex and may be helpful in the early ini- tiation of ejection. Physiologically, stimulation of the nipple in the lactating woman results in the release of oxytocin by the hypothalamus, which then triggers the release of milk by stimulating the contraction of myoepithelial cells and the ejec- tion of milk (seeChapter 8). The effect of intranasal administration of oxytocin on the let-down reflex in lactating women was well described by Newton and Egli.31 (Oral administration by tablet is not as effective because oxytocin is destroyed in the stomach; therefore, oral administration must be
sublingual.) Oxytocin nasal spray has been used in cases of nonpuerperal lactation with some suc- cess in enhancing let-down but not necessarily altering the volume produced. The original oxyto- cin product, Syntonin, is no longer available, but a pharmacist by prescription can place the intrave- nous preparation in a dropper bottle or a nasal spray container. The intravenous preparation (10 units/
mL) is one quarter the strength of the old nasal spray (40 units/mL). Therefore, the dose needs to be increased four-fold: 4 to 6 drops per dose in one naris and feed the infant or pump immediately (seeChapter 8). The dose can be repeated. Contin- ued use of oxytocin for weeks has been associated with diminished effect or even suppression of lactation.
In a randomized, double-blind trial of oxytocin nasal spray in mothers expressing breast milk for preterm infants, there were only marginal differ- ences in the pattern of early milk production.
The use of oxytocin nasal spray did not signifi- cantly improve outcome. Most of the subjects thought they were receiving the real medicine, which demonstrates the power of the placebo effect. All the mothers had been pregnant, and their breasts had responded to the pregnancy. These data should not be extrapolated without further study to women who had never been pregnant.
The chief benefit of oxytocin is often to break the cycle of failure and instill a feeling of confi- dence once it has been demonstrated that some secretion can be produced.
Chlorpromazine has been observed to act as a galactagogue as well as a tranquilizer when given to patients in large doses (as high as 1000 mg).
The effect has been observed in both male and female patients in mental institutions. The drug has been reported to increase pituitary prolactin secretion several fold. It acts via the hypothalamus, probably by reducing levels of prolactin inhibitory factor (PIF). Using this information, women well motivated to lactate who have attempted induced lactation by suckling a normal infant have had the process enhanced by small doses of chlorpro- mazine (Tables 19-1Aand19-1B).
In a program to induce lactation in refugee camps in India and in Vietnam, nonlactating women were given 25 to 100 mg of chlorpromazine three times per day for a week to 10 days while infants were initially put to breast. Brown9reports apparent enhancement of lactation with this treat- ment. Chlorpromazine has the added pharmaco- logic effect of acting as a tranquilizer. The program of management in these women was sup- portive in other ways and also included the usual herbal medicines associated with lactation in these Eastern cultures. There was no control group.9It is possible that the drug contributed to both the
TABLE 19-1A Pharmacologic Agents to Induce Lactation
Domperidone Fenugreek Metoclopramide Silymarin*
Possibly effective for selected indications Chemical class or
properties Dopamine antagonist A commonly used spice; active constituents are trigonelline, 4- hydroxyisoleucine, and sotolon
Dopamine antagonist Flavolignans (presumed active ingredient)
Level of evidence I (one study); other studies have inadequate methodology or excessive dropout rates
II-3 (one study in lactating women—
abstract only)
III (mixed results in low-quality studies;
effect on overall rate of milk secretion is unclear)
II-I (one study in lactating women)
Suggested dosage 10 mg, orally, three times per day in the Level I study; higher doses have not been studied in this context
“3 capsules” orally (typically 580- 610 mg), three to four times per day;
strained tea, 1 cup, three times per day (ẳtsp of seeds steeped in 8 oz of water for 10 minutes)
10 mg, orally, three to four times per day
Micronized silymarin, 420 mg orally per day; anecdotal:
strained tea (simmer 1 tsp of crushed seeds in 8 oz of water for 10 minutes), 2-3 cups/day Length/duration of
therapy
Started between 3 and 4 weeks postpartum and given for 14 days in the Level I study. In various other studies the range was considerable:
domperidone was started between 16 and 117 days postpartum and given for 2-14 days
1 week 7-14 days in various
studies
Micronized silymarin was studied for 63 days
Herbal
considerations
— Need reliable source
of standard preparation without contaminants
— Need reliable
source of standard preparation without contaminants Effects on lactation Increased rate of milk
secretion for pump- dependent mothers of premature infants of less than 31 weeks’
gestation in neonatal intensive care unit
Insufficient evidence;
likely a significant placebo effect
Possibly increased rate of milk secretion; possible responders versus nonresponders
Inconclusive
Untoward effects Maternal: dry mouth, headache (resolved with decreased dosage), and abdominal cramps.
Although not reported in studies of lactation, cardiac arrhythmias due to prolonged QTc interval are a concern and are occasionally fatal. This may occur with either oral or intravenous administration and particularly with high
Generally well tolerated. Diarrhea (most common), unusual body odor similar to maple syrup, cross-allergy with Asteraceae/
Compositae family (ragweed and related plants), peanuts, and Fabacceae family such as chickpeas, soybeans, and green peas—
possible anaphylaxis
Reversible CNS effects with short- term use, including sedation; anxiety;
depression/anxiety/
agitation; motor restlessness;
dystonic reactions;
extrapyramidal symptoms. Rare reports of tardive dyskinesia (usually irreversible), causing the FDA to place a boxed warning on this drug
Generally well tolerated;
occasional mild gastrointestinal side effects; cross- allergy with Asteraceae/
Compositae family (ragweed and related plants)—possible anaphylaxis
Continued