The natural purpose of the female human breast is to provide sustenance and nourishment to babies. While almost all transsexual women proudly regard their breasts as an important sign of their femininity and womanhood, few really consider their biological purpose.
Some years ago an English newspaper published a story about a young woman breast-feeding her baby in a restaurant, she was asked to leave and wasn't at all happy about that. Not really headline material, but readers then discovered that the woman in question was a male-to-female transsexual. As a 'husband', she had begun female hormone treatment at about the same time as his/her wife had become pregnant. After the baby's birth, the transwoman had acupuncture to help kick-in her own milk production and was sharing nursing duties with her former wife. The story was inevitably intended to be rather sensationalist, but some transsexual women reading it were probably surprised to learn that their breasts might be capable of performing the function that they were intended for by nature.
The breasts of a transsexual woman are in fact quite capable of producing milk ("lactation") given the following circumstances:
One study of 27 genetic women who undertook a lactation induction programme found that 24 (89 percent) were successfully breast feeding well-nourished children. All 11 women who had never previously lactated were successful.
Whilst quite such a high success rate cannot be achieved with male-to-female transsexual women, there's no doubt that given a high degree of motivation combined with medication, support, and encouragement; lactation induction can often be successful in transsexual women.
With a breast that has been surgically enlarged with implants, the nipple may be more or less sensitive than normal. If the nerves around the areola were not cut or damaged during the surgery then it should still be possible to nurse fully or partially. Nerves are vital to breastfeeding since they trigger the brain to release prolactin and oxytocin, two hormones that affect milk production. The chances of breastfeeding also improve if the milk duct system is intact. It's impossible to know the full extent of damage — if any — until a woman tries to make and express milk. Once lactation starts, implants may also cause exaggerated breast engorgement with more intense than normal pain, fever, and chills.
The likelihood that implants cause serious lactation and milk production problems depends directly upon the kind of surgery had. Incisions that were made under the fold of the breast (inframammary) or through the armpit (transaxillary ) shouldn't cause any trouble. However, the popular periareolar method, making a "smile" incision around the areola, has greater risk of problems.
There's absolutely no evidence that silicone from silicone implants leaks into breast milk, but even if it did, it probably wouldn't harm a baby. Silicone is very similar to a substance used to treat a baby's stomach gas.
In order to be able to produce milk internally the breast must have certain structures in place, but fortunately these are present at birth in every human, whether genetically male or female. It's also worth noting that highly visible factors such as breast size and areola diameter that are often of great importance to transsexual women in fact have relatively little effect on the breasts potential ability to lactate and the quantity and quality of the milk that will be produced. Whatever the size of her breasts, a M2F transsexual woman can still potentially breastfeed if the internal structures are in place and undamaged.
Mammogenesis commences at puberty with the onset of oestrogen secretion by the ovaries, usually between the ages of 10 and 12 in the girl. Oestrogen causes enlargement of the mammary fat pad, one of the most oestrogen-sensitive tissues in the human body, as well as lengthening and branching of the mammary ducts. About 40% of male children also initiate mammary development during puberty due to the tendency of the testis to secrete significant quantities of oestrogens in early phases of its development. As testosterone secretion increases this function is lost.
Oestrogen stimulates breast growth by acting on the mammary tissue. With the onset of the menstrual cycle the presence of progesterone stimulates the partial development of mammary alveoli, so that by the age of 20 the mammary gland in the woman who has not been pregnant consists of a fat pad through which course 10 to 15 long branching ducts, terminating in grape-like bunches of mammary alveoli. In the absence of pregnancy the gland maintains this structure until menopause.
Mammogenesis is completed during pregnancy, with the gland becoming able to secrete milk sometime after mid-pregnancy.
Lactogenesis (referred to as the time when the milk "comes in") starts about 40 hours after birth of the infant and is largely complete within five days.
When nursing has ceased the gland undergoes partial involution, losing many of its milk producing cells and structures, a process which is only completed after menopause.
Development in the Transsexual Woman
The amount of hormone induced breast development achieved in the genetically XY male transsexual woman is very age dependent. Young boy-to-girls who start female treatment during their normal puberty years (i.e. about age 12-16) are likely to reach near normal breast development. But unfortunately the amount of development that can be expected rapidly tails off as the age of the commencement of hormone increases, and older transsexual women will commonly suffer from underdeveloped (hypoplastic) breasts.
Breast development is categorised by the "Tanner Stages" scale which goes from I to V. It can again be emphasized that there is really NO minimum degree of breast development in order to be able to lactate; there are well documented instances of even men with minimal Tanner I breasts producing some milk and breast feeding without using hormones. On the other hand there is no doubt that the higher the development stage, the easier it will usually be to start lactation and the greater the likely quantity of milk produced. In general, well developed Tanner IV or V type breasts are really required for successful nursing of a baby, perhaps a majority of the girls who start hormone treatment by age 25 are likely to achieve this but most older woman will achieve no more than Tanner III or even II breast development. Such hypoplastic breasts are very small or narrow, lack normal fullness, and may seem bulbous or swollen at the tip. They are also likely to be widely spaced and one breast may be larger than the other. Hypoplastic breasts don't develop and grow in response to any additional hormones given in order to simulate pregnancy and prepare the breast for lactation. Breasts of this kind have fewer milk glands than normal, leading to milk-production problems.
Breast Development During Pregnancy
It is necessary to understand how the human breast develops and prepares for milk production during a woman's pregnancy.
Mammogenesis is completed during pregnancy - indeed pregnancy is the period of greatest mammary growth. Extensive lobular and alveolar development occurs only during pregnancy, also milk secretory cells only develop during pregnancy, therefore this period is extremely important in determining the number of secretory cells in the lactating gland and the subsequent production of milk. Mammary growth (of the mother) accelerates throughout pregnancy and is fastest during the later stages of pregnancy, which coincides with the most rapid period of foetal growth.
Structure of a Pregnant Woman
But perhaps even more remarkable than this visible transformation are the extensive changes taking place inside her breasts, primarily under the stimulation of high levels of oestrogen and progesterone, combined with the rising levels of prolactin from the pituitary and human placental lactogen (HPL) from the placenta.
Nestled amid the breasts fat cells and glandular tissue is an intricate network of channels or canals called milk ducts. The additional hormones released during pregnancy cause the cells of the mammary fat pad to diminish in size and their place is taken by the developing ducts and alveoli.During the first three months of pregnancy the milk ducts increase in number and size; the ducts starting to branch off into smaller canals near the chest wall called ductules. During the mid-three months a cluster of small, grapelike, sacs called alveoli appear at the end of each ductule. A cluster of alveoli is called a lobule; a cluster of lobules is called a lobe. Each breast contains between 15 and 20 lobes, with one milk duct for every lobe. During the last three months of pregnancy the alveoli grow and mature.
Milk is produced inside the alveoli, which are surrounded by tiny muscles that squeeze the glands and push milk out into the ductules. Those ductules lead to a bigger duct that widens into a milk pool or milk sinus directly beneath the areola. Milk pools (also known as sinus) act as reservoirs that hold milk until a baby suckles it through tiny openings in the nipple. Essentially the 15 or 20 milk ducts act as individual straws that all end at the tip of the nipple and deliver milk into a baby's mouth.
The mammary gland becomes able to secrete milk sometime after mid-pregnancy, and begins to produce small amounts of a protein- and fat-rich secretion sometimes referred to as precolostrum. It seems likely that mammary development continues through the duration of pregnancy since milk secretion by mothers of premature infants often appears to be diminished. The onset of copious milk secretion (or lactogenesis) is held in check by the high levels of circulating progesterone until after child birth.
Differentiation of the breast to its mature status occurs by the third month of pregnancy, although it will take about 6 months for the breast system to fully develop and become functional for lactation. Indeed, mammary growth will continue right up to birth, and even after if nursing. In a pregnant woman, by time the baby is born, glandular tissue has replaced most of the fat cells and accounts for the much enlarged breast. The increase in size varies greatly with the individual, ranging from zero to 800 cc of volume (and 1½ lb of weight!) per breast; the average being about 400 cc. It is normal for women to increase by one or two cup sizes during pregnancy, although this will decline (sometimes dramatically) after the cessation of lactation.
Oestrogen and Progesterone
Oestrogen and progesterone together establish the conditions needed for geometric cell multiplication to occur. For example, from one original cell, 8 cell divisions yields 128 cells.
During pregnancy, the mammary tissue has oestrogen receptors and progesterone receptors. During lactation the mammary gland has oestrogen receptors, but not progesterone receptors.
Prolactin is a protein hormone secreted from the anterior pituitary gland, as well as assisting in breast development; it stimulates and controls the actual production of milk.
In a pregnant woman, the placenta produces an important hormone called Human Placental Lactogen (HPL) which adjusts the maternal metabolism. One of its functions is similar to prolactin, i.e. stimulation of milk production by the mammary glands. HPL seems to work with oestrogen and progesterone to increase the number of alveoli in mammary glands and also plays a role in making the alveoli functional (capable of producing milk). It's thought that the level of HPL hormone activity in the maternal blood regulates the extent of mammary development during late pregnancy. HPL also causes the secretion of a form of milk called colostrum from about the fifth month of pregnancy.
Yet another, and apparently unimportant, hormone is secreted by the pituitary gland of a pregnant woman, Melanocyte Stimulating Hormone (MSH). Its only known effect is to stimulate the skin to produce pigmentation, causing the aeroli to enlarge and darken.
Milk Production in a Maternal Mother
Lactogenesis is associated with an abrupt increase in milk volume secretion, which goes from a mean of about 50 ml per day on day 2 of lactation to about 500 ml per day on day 4. After this time there is a gradual volume increase to about 850 ml/day by three months postpartum. There are also profound changes in milk composition during the early post child birth period as the production of milk products comes into high gear. By 10 days after child birth the milk has assumed the composition characteristic of mature milk. There are minor composition changes that continue throughout lactation. Full lactation, or the secretion of mature milk, continues as long as the demand is there, up to three to four years for infants in some cultures.
Three factors are necessary for successful lactogenesis: a developed mammary gland, continued high plasma prolactin levels, and a fall in progesterone and oestrogen levels that otherwise inhibit lactation - it can therefore be partially inhibited by high doses of oestrogen. It is important to note that the milk "comes in" at the same rate whether the infant suckles during the first 48 hours or not. Thus the onset of milk secretion depends, not on milk removal from the breast, but on the changes in hormonal status associated with child birth. However, continued milk secretion depends on milk removal from the breast, the involutional process sets in after only 3 to 4 days if breast-feeding is not initiated.
Breast Stimulation in the Transsexual Woman
It is appropriate at this point to distinguish between trying to achieve some slight lactation, ranging from a few drops up to as much as 35% that of a nursing mother, and trying to achieve full and copious milk production. Both require some degree of hormonal stimulation, but it's a case of for how long, and also how well the breasts respond to the hormonal stimulation.
If only a minimal degree of lactation is being attempted then the high oestrogen regimen may be as short as two weeks. But if full lactation is desired, then the transsexual woman must try to induce all the necessary developmental changes in her breasts by simulating a full period pregnancy by taking high doses of oestrogen and progesterone hormones for a period of at least six months (probably not coincidently, a premature baby born after the 28th week or sixth month of pregnancy is "viable" and will often survive, and will thus require feeding). This sustained hormone treatment may stimulate her breast in to developing and preparing for lactation, but unfortunately transsexual women with underdeveloped hypoplastic breasts are unlikely to succeed in this endeavour as their breasts will fail to respond to the additional hormones.
Also, in a pregnant woman her production of the estriol type of oestrogen greatly increases and it becomes the dominant type of oestrogen in her body. When present in high levels (unlike the non-pregnant lower levels), one of its effects is to help prepare the breast for milk production. However, the "weak" estriol oestrogen is rarely taken by transsexual women as part of their hormone therapy, instead standard oestrogen prescriptions are either of the estradiol (e.g. the Estrace brand) or estrone (e.g. the popular Premarin brand) types. Unfortunately, prolonged taking of large doses of these "strong" oestrogen types, as is common with transsexual women, seems to de-sensitise the body to estriol, making stimulating the breast to prepare for lactation via hormones much more difficult.
Assuming that the hormones have an effect, the period of the most visible breast growth is often during the first eight weeks of treatment. This enlargement is potentially just temporary as it's primarily due to engorgement of the blood vessels, enabling increased circulation to the breasts. Thereafter, oestrogen hormones stimulate cell mitosis and growth of the ductal system, the development and differentiation of the glandular tissue (lobules and alveoli) is dependent on progesterone, whilst breast fat accretion seems to require both.
Regarding the other hormones found in pregnant woman:
Stress, tension, and fatigue all produce hormones that can reduce let-down. Avoid smoking and excessive alcohol and caffeine - these are known to inhibit a mother's milk production and let-down.
In order to pump effectively and increase milk supply it is essential to relax and stimulate as much as possible the milk let-down response crucial to milk expression. Suitable mental or environmental stimuli such as baby photo's, imagining yourself breast feeding, direct sucking stimulation of the nipples and immediately surrounding tissue, playing a tape of the cries of a hungry baby, ... etc, are essential aids to milk production. And a partner can greatly assist with sexually arousing mental stimulation and manual manipulation of the woman's body before, and even during, her expression period.
Here are some tips to help both manual and mechanical expression:
Achieving Milk Production in the Transsexual Woman
As the body readies itself for lactation, it pumps extra blood into the
alveoli, making the breasts firm and full. Swollen blood vessels,
combined with an abundance of milk, may make the breasts temporarily painful
and engorged, but nursing or expressing frequently in the first few days
will help relieve any discomfort.
When oxytocin reaches the breast it causes the tiny muscles around the milk-filled alveoli to contract and squeeze. The milk is emptied into the ducts, which transport it to the milk pools just below the areola. When s/he suckles, the nursing infant presses the milk from the pools into his mouth, both manual and mechanical expression techniques can simulate this to a reasonable degree.
As the milk flow increases, the lactating woman may feel some tingling, stinging, burning, or prickling in her breasts. The milk may drip or even spray during let-down.
A benefit of oxytocin is that it the nursing woman may feel calm, satisfied, and even joyful as she nurses or expresses.
The volume of milk produced is primarily a function of demand and is unaffected by maternal factors such as nutrition or age. Not a lot of milk will be produced unless suckling (natural or artificial) is frequent and consistent, the milk itself contains an inhibitor of milk production that builds up if the milk remains in the mammary gland for a prolonged period of time. Adequate milk removal from the breast is absolutely necessary for continued milk production.
If nursing an infant is not immediately and regularly possible then in order to maintain milk flow it will be necessary to artificially stimulate let-down by expression using a breast pump.The more you nurse or express, the more milk that will be produced - nursing 10 to 15 minutes per breast every 2-3 hours (day and night!) is optimum! Expressing less than once every 5-8 hours, will result in dramatically less milk production, although some milk production will continue so long as an infant is suckled or milk is expressed at least twice per day. Less than that will result in complete cessation of milk production within one to three weeks. But with sufficient and regular stimulation, it is quite possible to maintain lactation for months, even years.
Two hormones are necessary for this continued production: oxytocin and prolactin. As mentioned above, oxytocin is necessary for the milk ejection reflex that extrudes milk from the alveolar lumen. Prolactin is necessary for continued milk production by the mammary alveoli. The secretion of both hormones is promoted by the afferent nerve impulses sent to the hypothalamus by the process of suckling. However, whereas the secretion of oxytocin is highly influenced by the activity of higher brain centres, prolactin secretion appears to be determined primarily by the strength and duration of the suckling stimulus. Although prolactin levels fall with prolonged lactation, at least some basal level appears to be necessary for continued milk production. There appears to be no direct relation between prolactin levels and milk production and therefore it is thought that the rate of milk production depends on control mechanisms localized within the mammary gland.
Feeding by Transwomen
"A lot of women who adopt go through a regimen of hormones before they have their child, and that enables them to breastfeed by the time they get their child. So I just did the same protocol. It's basically simulating pregnancy with hormones, and since I transitioned 10 years ago, I had enough breast development where it was basically the identical situation."
it worth it?
the Ask Lenore
However it may be worth having a manual breast pump as well the electrical. The big advantage of a manual pump is that being light and small it can be conveniently carried in your bag when you know that you will be unable to meet a scheduled session on your electrical pump. If you are working, 30 minutes hidden in the toilets at lunch time using a hand pump may be the only option if the alternative is going more than about 6 hours without pumping. And a whole day without pumping might undo months of hard work and take you back to nearly the beginning! Because hand-pumps are cheap, it's possible to buy a couple of different models and experiment to find the one that is most comfortable, gives the best fit and suction to your breasts, is the most comfortable in the hand, and is the least tiring to use.
Lactation Enhancing Drugs
Genetic women trying to start lactation are advised that prolactin enhancing drugs need only be started only after the ending of any oestrogen treatment as oestrogen, particularly those types found in contraceptive pills, retard the start of lactation. However many transsexual women seem to gain considerable benefits from the breast developing effects of prolactin even if it's not initiating lactation because of their high oestrogen intake, and thus should not be deterred from early use.
Unfortunately Motilium is not yet available in the USA so domperidone may have to be used instead - usually just for 4 weeks rather than continuously. Also, in rare cases Motilum may cause stomach or digestive upsets and so domperidone may be preferred.
Some women find that herbal seed capsules such Blessed Thistle and Fenugreek help increase their lactation, and these are very commonly taken.
Some "morning sickness" and nausea is very probable at first, if more severe side effects are experienced then medical help should be sought immediately. Long term use of such high dosage levels should be avoided, and if it's clear that no beneficial effects are occurring within 6-8 weeks then the regimen should be abandoned and the previous hormone regimen reverted to.
"Attempted lactogensis" means reverting to the prior hormonal regimen in order stimulate the start of milk production and lactation, this must involve a considerable reduction in oestrogen and progesterone hormone intake, in pre-SRS women it may actually require a reduction to less than their normal regimen. If a baby is to be nursed then medical advice should be sought as to what hormones can still be safely taken and in what dosage, and any anti-androgens being taken must be stopped. Prolactin-enhancing drugs should continue to be taken, e.g. 2 Motilium tablets every 6 hours, each containing 10 mg domperidone maleate.
Antiandrogens may also be helpful to a pre-SRS transsexual women trying to induce lactation, although they should never be taken by a pregnant woman, or subsequently if breast feeding. The most commonly used antiandrogens are spironolactone (brand name Aldactone), flutamide (Eulexin) and cyproterone acetate (Androcur). Spironolactone, in a dosage of 25 to 100 mg administered twice daily, is the most commonly used antiandrogen because of its safety, availability and low cost. Flutamide is usually given in a dosage of 250 mg twice daily, and cyproterone is given in a dosage of 25 to 50 mg per day. Pre-SRS women may well already be taking much higher dosages of antiandrogens and these should not be increased - indeed in some cases it may be advisable to change the drug or reduce the dosage to the levels given here.
Nutritional Value of Induced Milk
La Leche League International publishes the useful booklet "Nursing the Adopted Baby"
Information on lactation inducement can be found at The Adoptive Breastfeeding Resource Website
Some very interesting information and protocols for induced lactation can be found at Asklenore.info
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