Cosmetic Surgery Tips

Breast Enlargement In Newborn

Neonatal breast enlargement is a very rare condition that affects only 1 out of every 10,000 babies. It is characterized by rapid growth of the breasts during the first few weeks after birth, and then the breasts stop growing and remain enlarged for at least six months or longer.

There are three types of neonatal breast enlargement:

1) True hyperplasia – The most common type of neonatal breast enlargement, this condition occurs when there is an increase in glandular tissue. This can be caused by hormones, drugs, or genetic factors.

2) Pseudohyperplasia – This type of breast enlargement occurs when there is an increase in fat cells instead of glandular tissue. Pseudohyperplasia may occur as a result of genetic factors or it may be caused by certain medications taken during pregnancy (such as steroids). It usually goes away on its own within a few weeks after birth.

3) Parenchymal neoplasia – This rare condition occurs when cancerous cells develop in the breast tissue and begin to grow uncontrollably.

In this article we”ll answer question like neonatal breast enlargement treatment and newborn baby breast lump.

Breast Enlargement In Newborn

Maternal estrogen is known to cause varying degree of breast enlargement in approximately 70% of newborn. [1] Usually the diameter of breast bud measures 1 to 2 cm in the first few weeks of life [2]. But Athena has seen some of these breasts of alarming size (Figure 1). The reason for this exaggerated response is unclear. These giant breasts will be hard and tender in contrast to the soft and painless gynecomastia of older children and adolescents. Postnatally, falling levels of maternal estrogen is thought to trigger prolactin secretion in the pituitary of the newborn [1,3]. Resultant prolactinemia stimulates neonatal breasts and causes milk secretion in 5 to 20% of newborn [4]. It is popularly known as witch’s milk because it is believed in folklore that witches and goblins would feed on it [5]. Witch’s milk resembles maternal milk with identical concentration of IgA, IgG, lactoferrin, lysozyme and lactalbumin [6]. Inadequate let-out of milk, either due to improper canalization of lactiferous ducts or due to lack of oxytocin stimulus in the newborn, may lead to stagnation of milk (galactocele). Superadded infection may result in complications such as mastitis and breast abscess [7]. Athena intended to update the recent developments on this oddity of the Nature.

Figure 1: Giant Mastauxe of newborn

An extensive review of literature has left Athena much disappointed for many reasons. First of all, there is no proper terminology to describe uncomplicated, physiological enlargement of breasts in the newborn. Research papers seldom distinguish various forms of breast swellings in newborn such as physiological enlargement, exaggerated development, bulging galactocele, inflammatory swelling and breast abscess. Terms such as ‘mastitis’ [8,9,10], ‘galactorrhea’ [4,11], ‘gynecomastia’ [11,12], ‘galactocele’ [12,13], ‘breast hypertrophy’[14] and ‘breast enlargement’[1] have been used interchangeably to denote any of the aforementioned presentations. Notoriously, hardness (induration), hyperemia and tenderness of proliferating mammary glands are often mistaken for the signs of inflammation and hence the popular misnomer “Mastitis Neonatorum” [8]. Considerable overlap of the various presentations further mars the clarity. Imprecise terminology, lack of accurate definition and absence of diagnostic criteria have left much confusion in the literature [4]. Considerable etymological research prompted Athena to revive an obsolete term – “Mastauxe” (pronounced as mas-tawk′sē). It is a combination of two Greek words mastos (Breast) and auxein (increase in size) [15,16]. Semantically, it appears to be the right word to describe uncomplicated physiological breast enlargement of newborn under hormonal influence. The terms “neonatal mastitis”, “neonatal breast abscess” and “neonatal galactocele” are better reserved to denote complications of “neonatal mastauxe”. Exaggerated breast enlargement may be referred to as “giant mastauxe” (Table 1).

An external file that holds a picture, illustration, etc.
Object name is jns-2-31.f2.jpg

Table 1

Adding to the lexicological confusion, the literature is also undermined by poor quality research. Almost all the available papers are either anecdotal case reports or small case series. Large clinical trials and experimental studies are conspicuously missing over the last 5 decades. Three recently published case series [8,9,10] do not add anything significantly to the existing knowledge (Table 2). Commonality of the 3 papers can be summarized as follows: Neonatal mastitis is common in full term female neonates during the third and fourth week of life. Bilateral involvement is rare (< 10%). There is no side predilection. Maternal endocrinopathy was noted in 0 to 14% of cases. Staphylococcus is the commonest isolate accounting for more than 60% cases. With or without pretreatment, 50 to 70% of them progress to become breast abscess requiring needle aspiration or surgical drainage of pus. About 30 to 60% of the neonates needed hospital admission for intravenous antibiotics or for surgical treatment. Although systemic manifestations are generally rare (8 to 28%), serious life-threatening systemic complications such as cerebral abscess have been documented in the literature [17,18]. Ruwaili and Scolnik [9] noted that approximately one half of neonatal mastauxe is complicated by mastitis and one half of neonatal mastitis progresses to become frank abscess. Neonatal mastitis showed cluster occurrence in Brett’s series [8]. Long-term follow-up is uniformly missing in all the studies.

An external file that holds a picture, illustration, etc.
Object name is jns-2-31.f3.jpg

Table 2

It is often difficult to say with certainty as to when mastauxe becomes true mastitis because they frequently share the same physical signs. Athena is curious if modern imaging modalities can distinguish the two. Borders et al. [19] studied sonographic appearance of mastitis in 5 newborns. Breast buds were relatively hypoechoic in mastauxe while increased echogenicity is characteristic of mastitis. Breast abscesses may be either anechoic or echogenic depending upon the nature of their contents. Both abscess and mastitis show increased flow pattern of surrounding fat in color Doppler; but flow within the abscess is singularly absent. The authors recommended sonographic examination if the response to antibiotic is delayed or if there is a suspicion of abscess formation. Welch et al. [20] indicated that ovoid masses of anechoic areas with intervening septae could suggest duct ectasia especially when the septae show vascular flow in color Doppler. But these findings are based on a very small number of observations and they need to be reconfirmed by larger studies. Mastauxe is incidentally noted to exhibit increased uptake of Technetium99m pertechnetate during thyroid scintigraphy [21,22]. Practical significance of this interesting observation is yet to be studied.

Mastitis or its surgical treatment may cause damage to developing breast bud. Impaired development and asymmetry of breasts in adulthood is traditionally considered to be a serious complication of neonatal mastitis [7]. Recently, Panteli et al. [23] provided a modest scientific evidence of this assertion. They followed-up 8 neonates with mastitis into their adolescence. Seven of them had undergone surgical drainage of neonatal breast abscess. The mean age at follow-up was 14 years (range 10 – 15 yrs). Half of the patients had abnormal finding in clinical and/ or sonographic examination. This included reduced breast size in 2 (25%), altered breast texture in 4 (50%) and breast asymmetry in 1 (13%). This paper underlines the importance of prompt intervention and long-term follow-up of neonatal mastitis.

The mystery as to why some neonatal breasts show exaggerated response to hormones is unclear. It is probably attributable to hypersensitivity of breast tissue to estrogen and/ or prolactin. If this hypothesis is true, estrogen being a known carcinogen, giant mastauxe will be more vulnerable for malignant change in adulthood. French molecular oncologists have shed some light on this important question. Recently they showed that both BRCA1 and BRCA2 (tumor suppressor genes of breast cancer) are over expressed in infantile gynecomastia of a 2-year-old boy [24]. Further studies are required to ascertain the oncogenic risk of mastauxe.

Neonatal mastauxe requires simple observation and parental reassurance. Repeated expression of witch’s milk by manual squeezing has been strongly discouraged as it is believed to prolong milk secretion and introduce infection [25]. Buehring [26] while studying the diagnostic utility of witch’s milk in 106 infants, confirmed the former and refuted the later. Repeated manual emptying of glands, indeed, prolonged milk secretion as long as 24 weeks and significantly increased the amount of milk from 20 µl to 1500 µl per sample. Despite repeated handling of breast, none of the 106 infants developed infective complications such as mastitis or abscess. Finally, Athena is amused by Buehring’s speculation that witch’s milk analysis could be a useful adjunct in the diagnosis of certain inborn errors of metabolism. Concentration of phenylalanine in witch’s milk is higher than that in neonatal blood. Therefore, hypothetically, witch’s milk analysis may increase the diagnostic yield of neonatal screening for phenylketonuria [26].

Swollen Breasts in Newborns

The normal newborn breast diameter is about 1-2 cm. Breast swelling of various degrees can occur in about 70% of newborns, and is called by various names. Some of them include physiological breast enlargement, greater breast development, gynecomastia of the newborn, neonatal mastitis and breast enlargement.

The swelling may be soft or hard, and is recognizable by the third day of life. The breasts are somewhat tender, and occasionally, in about 5-20 percent of newborns, breast milk is also secreted from the swollen breasts for a couple of weeks. This used to be called witch’s milk under the impression that witches liked to drink it, but it is actually indistinguishable from ordinary human breast milk.


Pregnancy is associated with high levels of the female hormones estrogen. It passes through the placental circulation into the fetal bloodstream. This is responsible for many changes seen in the newborn as well including gynecomastia and vaginal swelling, just as it is in the pregnant woman. For this reason breast tissue in infants of both sexes responds to the elevated levels of the hormone by proliferating and enlarging. As delivery draws near, the level of estrogen falls and prolactin levels rise within the pituitary gland, in response. This leads to milk secretion.

It is not yet clear why only some newborns show greater breast development. It is thought that they may be hypersensitive to the effects of estrogen and/or progesterone. In at least one case, an overexpression of BRCA1 and BRCA2 receptors was found. This may be responsible, in which case more study is required on the future risk of malignant changes in such individuals.

Course and Prognosis

In most cases no treatment is required because the levels of estrogen and prolactin go down to normal over two weeks following birth, as they are metabolized in the newborn’s body.

In a few newborn infants, milk is not let out normally due to defects in canalization of the lactiferous ducts, or because of poor oxytocin secretion which promotes milk secretion. As a result, milk accumulates within the breasts, causing a galactocele to form. The entrance of infectious organisms into this receptive pool of milk may lead to the development of neonatal breast infection, which complicates about 25% of these cases. In about 70 percent this results in the formation of a breast abscess. This is more common in full term female infants between the third and fourth weeks after birth. In 9 out of 10 infants only one side is infected. Most cases are due to Staphylococcus infection.


Isolated gynecomastia subsides without any need for treatment. The breasts should not be squeezed as this only encourages the expression of milk by a hundredfold. Simple observation is all that is required.

However, when a breast abscess forms, it will require surgical treatment, either needle aspiration or surgical drainage of pus. As such, hospitalization will be necessary for surgery or intravenous antibiotic administration in 30-60 percent of these cases. Overall, about a quarter of neonates with breast enlargement go on to develop breast abscesses. Systemic spread is rare, but does occur.

Neonatal Breast Enlargement Treatment

A newborn female presented with enlarged breasts on both sides. Her Apgar scores at 1 and 5 minutes of life were 8 and 9, indicating a healthy birth. She appeared to be in no pain or distress and was happily sucking away. The breasts were enlarged, but there was no sign of tenderness or discharge when the patient’s chest was examined. At birth, the mother noticed a slight swelling in the breasts, which continued to increase over the next few days. Increases in prolactin production by the newborn’s pituitary gland are a normal reaction to decreasing levels of maternal estrogen near the end of pregnancy, resulting in the characteristic enlargement of the breasts characteristic of newborns. About 70% of newborns experience neonatal breast enlargement, and this occurs regardless of the baby’s sex. This patient had the typical presentation during the first week of life, and it went away after a few weeks. Sometimes fluid will drain from the enlarged breast; this usually stops happening after a few weeks even without treatment. Squeezing the breast to encourage drainage can cause irritation, growth, the hypertrophied tissue to persist, and even infection in rare cases (mastitis or abscess).

Newborn Baby Breast Lump

All newborns, male and female, often have soft, enlarged breasts and/or lumps under the nipple. Prenatal exposure to maternal hormones is the most common cause, and these growths are typically harmless. Breast development in a baby can be influenced by the same hormones that stimulate milk production in the mother.

The baby’s breasts may be noticeably enlarged and lumpy. They may even keep growing for a while after birth. They might be able to produce some genuine breast milk if you pinched them.

When hormones are no longer present in the body, the breast tissue gradually decreases in size and flattens out over the course of weeks or even months. Sometimes, a typical, negligible amount of tissue is left behind, but it neither multiplies nor causes any symptoms.

An external file that holds a picture, illustration, etc.
Object name is jns-2-31.f1.jpg

Leave a Comment

Your email address will not be published. Required fields are marked *