Hormones

Key Points

Hormones play different roles during the body’s pregnancy and breastfeeding cycles
Studies show that estrogen and progesterone have been found in processed placenta pills
Hormones in the placenta are biologically known to suppress the hormones needed for milk synthesis

Continued exposure to hormones in placenta pills may actively down-regulate prolactin receptors, decreasing long term milk supply
Hormones in placenta are not needed to enhance lactation in a breastfeeding mom, and can even backfire
Thromboembolism (blood clots) are a risk for postpartum women from placenta ingestion due to the estrogens

Image used with permission

The hormones of breastfeeding and how placenta pills interact with them

Click here to see the anatomy and physiology of breastfeeding

PROLACTIN and its RECEPTOR

PROLACTIN

“The milk making hormone”

Prolactin is a polypeptide hormone that is synthesized and released by the cells in the anterior pituitary, called lactotrophs, and has over 300 separate biological activities and roles throughout the body (Hale and Hartman 2007). “Prolactin has numerous effects on the mammary gland, including its growth and development (mammogenesis), synthesis of milk (lactogenesis), and maintenance of milk synthesis (galactopoiesis)” (Hale and Hartman p 480).

Research shows that the hormone prolactin is critical for the establishment and the maintenance of lactation. “Secretion of prolactin by the anterior pituitary gland for ongoing lactogenic activity is dependent on a positive feedback loop. The suckling stimulus, in addition to regular emptying of the gland, is essential to promote prolactin secretion…levels of prolactin in the blood are the highest in early lactation and decline as lactation progresses. This observation suggests that the function of prolactin may differ during the course of lactation” (Hale and Hartman p 94).

Prolactin binds to specific prolactin receptors on the surface of milk making cells, called lactocytes, creating a pathway that leads to the switching on of the transcription of genes that regulate the secretion of milk proteins. Prolactin receptors are upregulated in the lactocytes at the time of birth and lactogenesis II (Hale and Hartman 2007).

“Prolactin levels rise during pregnancy from about 10 ng/mL in the nonpregnant state to approximately 200 ng/mL at term. Baseline levels do not drop back to normal in a lactating woman but average about 100 ng/mL at 3 months and 50 ng/mL at 6 months…this diminished level reflects the increased prolactin-binding capacity or sensitivity of the mammary tissue, which allows full lactation in the face of falling prolactin levels over time. It is interesting to note that the level of inhibition of prolactin that is necessary to suppress lactation is over 80%, meaning that the typical levels of prolactin seen in mothers in Western countries with term infants is considerably in excess of the levels required to maintain lactation. The high levels of prolactin seen during pregnancy and early lactation may also serve to increase the number of prolactin receptors” (Walker pp 119 – 120).

PROLACTIN RECEPTOR

“The ‘lock for the key’ to making enough milk”

According to lactation researchers, prolactin receptors are thought to be a determining factor to calibrating a mother’s milk supply. In the early weeks of lactation, prolactin levels are much higher than they need to be to maintain lactation, and may serve to upregulate their own receptor sites. This is critical for maintaining milk supply at 3 months postpartum and after, as prolactin levels naturally decline at that time (Riordan 2005, Walker 2017). However, a full milk supply is thought to be maintained due to this early proliferation of prolactin receptor sites. Placenta contains hormones that are known to decrease prolactin levels and also to directly down regulate prolactin receptor sites (Young et al. 2016, Johnson et al. 2018). This may lead to an immediate or a delayed suppression of milk supply if placenta is ingested in the postpartum period.

“The controlling factor in breast milk output is the number of prolactin receptors rather than the amount of prolactin in serum. More receptors may result in more than adequate milk production, even in the presence of lower prolactin levels” (Riordan p 77).

The body’s response to a hormone is partly determined by how many receptors for this hormone it has and how many are activated. During the establishment of milk supply in the early weeks after birth, milk removal is responsible for the activation of prolactin receptors. The more receptors that are activated in the breast, the more milk the mother will be able to produce for that baby. Therefore, the early weeks after birth appears to be a critical period for activating enough prolactin receptors in the breast for long-term milk production. Even with full milk production, several months into lactation the baseline prolactin levels will naturally decrease, reinforcing the importance of early proliferation of prolactin receptor sites (Mohrbacher 2010, Riordan 2005, Walker 2017).

“Lactation during pregnancy is inhibited by high levels of progesterone, which interfere with prolactin action at the alveolar cell receptor level. The inhibiting influence of progesterone is so powerful that lactation is delayed if placental fragments are retained after birth” (Riordan p 75). A study that analyzed mammary hormone and receptor interaction in vivo was published in Nature (1977), titled Prolactin-Progesterone Antagonism in Self Regulation of Prolactin Receptors in the Mammary Gland. In this study researchers showed that progesterone counteracts the effects of prolactin and serves to downregulate the proliferation of prolactin receptors (Djiane and Durand 1977).

Prolactin receptors have also been shown to be suppressed by another placental hormone, estrogens. Estradiol has been shown to decrease the number of prolactin receptors on the lactotroph membranes (Hale and Hartman 2007).

The higher and the more consistently the prolactin level rises during the early weeks after birth, it is thought that the more prolactin receptors are activated in the breast, thereby increasing her milk production potential for that baby. If fewer prolactin receptors are activated, her long-term milk production potential may be limited (Mohrbacher 2010).

Q: HOW COULD INGESTING PLACENTA HAVE AN EFFECT?

A: In order for the “milk making hormone” prolactin to accomplish the work of establishing and maintaining a full milk supply, the right hormonal environment is needed. Ingesting placenta after the birth is reintroducing into the body the pregnancy hormones estrogen and progesterone, which not only suppress milk synthesis, but could also potentially down-regulate the proliferation of prolactin receptors, which are vital for maintaining ongoing milk supply, especially after 3 months postpartum. Ingesting placenta pills in an effort to “gain prolactin” from the placenta is not necessary. The prolactin the body needs is provided by the pituitary gland during breastfeeding. The prepared placenta pills do not have any levels of prolactin in them. Click here for research on content of placenta pills.

GLUCOCORTICOID and its RECEPTOR

“A milk making partner that is counteracted by progesterone”

Glucocorticoid receptors are present on the mammary cells that make milk (lactocytes). Glucocorticoids act synergistically with prolactin to enable synthesis of milk proteins. Progesterone also binds to glucocorticoid receptors on lactocytes, creating an inhibitory action of progesterone on milk production during pregnancy. Progesterone prevents glucocorticoids from reaching sites for transcription of milk proteins. (Hale and Hartman 2007)

Q: HOW COULD INGESTING PLACENTA HAVE AN EFFECT?

A: Ingesting the placenta in the postpartum period could elevate progesterone levels that may act on the glucocorticoid receptors and inhibit their ability to produce milk in the lactocyte. This could work to suppress milk production.

PROGESTERONE

“The pregnancy hormone”

The hormonal environment of pregnancy is about maintaining the pregnancy, growing the fetus, and preparing the breasts for breastfeeding. Progesterone acts in pregnancy to not only help maintain the uterine environment for a healthy pregnancy, but also to work with the other pregnancy hormones to promote breast development at this stage. Progesterone is involved in lobule and alveolar development in pregnancy.

However, “The hormones affecting lactation play different roles during pregnancy, birth and breastfeeding” (Mohrbacher p 393). This high concentrations of progesterone during pregnancy also serves to inhibit lactogenesis II by suppressing the upregulation of prolactin receptors in the lactocytes (Djiane and Durand 1977).

Progesterone competes with glucocorticoid receptors in mammary epithelial cells, thus suppressing the lactogenic activity of endogenous glucocorticoids and as a result, suppresses milk production. (Hale and Hartman 2007)

“The delivery of the placenta at parturition (birth) in women leads to the reduction of progesterone in maternal blood, which in turn triggers the synthesis of lactose in lactocytes. Since it is the delivery of the placenta that initiates the fall in progesterone, lactogenesis II is therefore delayed until progesterone clears from the circulation, some 30 – 40 hours postpartum.” (Hale and Hartman p 98)

The World Health Organization’s Medical Eligibility Criteria for contraceptive use, fifth edition provides recommendations on use of progestin-only methods which may impact a woman’s milk supply. These guidelines include: Breastfeeding women from 48 hours to 4 weeks postpartum generally should not have a progestin (levonorgestrel) IUD inserted, and breastfeeding women who are less than 6 weeks postpartum generally should not use progestogen-only injectables. (WHO 2015).

Q: HOW COULD INGESTING PLACENTA HAVE AN EFFECT?

A: Progesterone is present in the placenta and has been found in bioactive levels in placenta pills. The hormonal environment needed for a breastfeeding woman will be at risk for critical alterations with reintroduction of progesterone from ingesting the placenta. Progesterone has been well studied with regards to it’s effects on suppressing milk synthesis and down regulating prolactin receptor sites. This may stunt the ability to establish a full milk supply over time. Placenta ingestion could limit a woman’s milk supply in both the short and long term of breastfeeding. Click here for research on content of placenta pills.

ESTROGEN

“The pregnancy hormone”

During pregnancy, estrogen is a vital hormone that is responsible for the regulation of other pregnancy hormones and the growth of the placenta, uterus and fetus. During pregnancy, estrogen is also involved in development of the mammary ducts. While naturally circulating and appropriate during pregnancy, it has an inhibitory effect on milk production, and has long been known to have a negative impact on milk supply during breastfeeding. The body’s natural hormonal cycling is to expel the placenta after birth, which naturally flushes out the circulating levels of pregnancy hormones, including estrogen and progesterone.

Estrogen is a hormone found in the placenta, and may have undesired effects when introduced during lactation. Certain medications may suppress prolactin secretion, including early use of oral contraceptives containing estrogen (Walker 2017).

Like progesterone, the influence of estrogen during lactation can also be seen in the inhibition of prolactin receptors, which may undermine long term milk production (Hale and Hartman 2007). In summary, “All mothers who take estrogen-containing birth control preparations should be forewarned of its possible effects on milk production” (Hale and Hartman, p 482).

The World Health Organization’s Medical Eligibility Criteria for contraceptive use, fifth edition, provides recommendations on use of combined hormonal methods, which may impact a woman’s milk supply. These guidelines include the following: breastfeeding women less than 6 weeks postpartum should not use combined hormonal contraceptives (containing estrogens and progestins), and from 6 weeks to 6 months postpartum generally should not use combined hormonal contraceptives. (WHO 2015).

Placental tissue contains estrogen, found in varying levels based on preparation method for consumption. Another risk of continued estrogen exposure for a woman is an increased risk of thromboembolism, which is a blood clot. Blood clots can lead to serious complications including stroke. Heathcare professionals are well aware of these risks and have guidelines to limit a postpartum woman’s exposure to this hormone.

Q: HOW COULD INGESTING PLACENTA HAVE AN EFFECT?

A: Estrogens are present in the placenta and have been found in bioactive levels in placenta pills. Click here for research on content of placenta pills. The hormonal environment needed for a breastfeeding woman could be at risk for critical alterations with reintroduction of estrogens from the placenta in pills or any other form. Estrogens are known to be potent suppressors of prolactin and milk supply. Placenta ingestion could limit a woman’s milk supply in the short and long term of breastfeeding.
See the section on Thromboembolism and Giving Placenta Products to Children to learn more.

PLACENTAL LACTOGEN

“The pregnancy hormone”

Placental lactogen is a hormone produced in the placenta. Along with prolactin, estrogen, and progesterone, placental lactogen stimulates growth of the mammary gland in pregnancy. Despite its name, it is considered only an accessory hormone for lactation in pregnancy. A major role it has in pregnancy involves regulating maternal metabolism and facilitating fetal growth, and “a role in human lactation is unclear” (Gurtunca and Sperling 2017). According to the authors of the Textbook of Human Lactation, “The lactogenic activity of placental lactogen occurs only during pregnancy and exogenous treatment during lactation has not been shown to have any effect on milk yield in sheep. Moreover, a role for human placental lactogen either in lactogenesis I or lactogenesis II has not been found in women” (Hale and Hartman p 98).

Q: HOW COULD INGESTING PLACENTA HAVE AN EFFECT?

A: While placental lactogen has an accessory role in the pregnancy cycle of lactation, like many other pregnancy hormones, placental lactogen has no role in lactation after pregnancy. Placental lactogen is not found in prepared placenta pills. Various marketing statements promoting placenta pills imply that due to its name, and because human placental lactogen is present in the placenta, it is a key hormonal player in lactation, and would be of benefit if administered postpartum. This is an inaccurate assumption that shows a misunderstanding of lactation physiology and current research. Click here for research on content of placenta pills.

OXYTOCIN

“The birth and milk ejection hormone”

Oxytocin is a peptide synthesized in the hypothalamus and then transported to the posterior pituitary, from which it is released into the bloodstream. The action of oxytocin in breastfeeding is to cause contraction of the smooth muscle myoepithelial cells surrounding the mammary alveoli, moving milk into the collecting ducts, and propel the milk toward the nipple. This is called “milk ejection,” or “milk let down.” Oxytocin is released in response to nipple stimulation and is delivered in a pulsatile nature from the pituitary gland, consisting of brief 3 – 4 second bursts into the bloodstream (Walker 2017). “Oxytocin cells fire bursts so that oxytocin is secreted in pulses. The breast responds to oxytocin only at relatively high concentrations, and rapidly desensitizes in response to continued exposure, so pulsatile delivery of oxytocin is essential for efficient milk ejection” (Walker p 123).

Studies show a feedback inhibition of oxytocin release may be induced as a reaction to high and unphysiological oxytocin levels during oxytocin infusions in labor. They also show increased cortisol levels in mothers who received oxytocin infusions during labor, and that this may be an expression of an increased sensitivity to some types of stress as a result of the lowered function in their oxytocinergic system, both within the brain and in the circulation. “Exogenous oxytocin thus has the potential to interrupt the initiation of lactation by (1) disrupting the endogenous pulsatile secretion of oxytocin; (2) augmenting the stress response, which replaces pulsatile secretion of oxytocin and with continuous secretion and inhibits lactation and (3) desensitizing and down regulating the myoepithelial receptors of oxytocin” (Walker p 123).

“The long term effectiveness of the administration of exogenous oxytocin for breastfeeding has not been studied” (Hale and Hartman p149).

Q: HOW COULD INGESTING PLACENTA HAVE AN EFFECT?

A: Ingesting your placenta to obtain oxytocin is not only unnecessary, as the body’s own built in system provides this hormone from the pituitary gland, but giving your body an outside source of oxytocin can backfire. A woman’s body is meant to release oxytocin from the pituitary in pulsatile waves in response to the baby suckling. These rapid bursts of oxytocin are how the body is meant to respond to oxytocin. The body not only stops responding to oxytocin if it is delivered into the system continuously, but this may also create a down regulation of it’s receptors, both of which could have a negative long term impact. Our bodies are designed to provide the oxytocin levels exactly how they are needed for breastfeeding, and do not need an outside source of this to make this natural system work. In addition, oxytocin has not been found in prepared placenta pills. Various marketing statements promoting placenta pills imply that because oxytocin is present in the placenta from the labor, that it will be present in placenta pills and be of benefit to lactation if ingested. This is an inaccurate assumption that shows a misunderstanding of lactation physiology and current research. Click here for research on content of placenta pills.

Placenta contains hormones

Placental tissue contains the hormones of pregnancy, which include estrogen and progesterone. Ingesting placenta in raw or pill form introduces a potential source of hormones into your body. Studies on prepared placenta for consumption shows varying levels of estrogens and progestins in placenta tissue, based on preparation and methods.

A 2016 University of Las Vegas (UNLV) study, Presence and Concentration of 17 Hormones in Human Placenta Processed for Encapsulation and Consumption, examined the hormones retained in processed placental tissue. After steaming and dehydration, the most thorough method of processing for encapsulation, they found that estrogens and progestins were retained in the pills at potentially bioactive threshold levels. Their report stated, “To determine whether free (unconjugated) steroid hormones and melatonin in placenta can survive the encapsulation process (namely steaming and dehydration), we analyzed 28 placenta samples processed for encapsulation using liquid chromatography tandemmass spectrometry (LCMS/MS) to evaluate the concentration of 17 hormones” (Young et al. 2016). The results of their study show that “while concentrations of many of the selected hormones are relatively low, mean concentrations of estradiol, progesterone, and allopregnanolone could potentially reach physiological effect thresholds” (Young et al. 2016).

A study published in 2018, Human Placentophagy: Effects of Dehydration and Steaming on Hormones, Metals and Bacteria in Placental Tissue, reported hormone content of raw and processed placenta, and found the highest concentrations of hormones in raw placental tissue. This study reported an 88.2% – 99.6% reduction in hormones in their method of fully processed, steam-dehydrated placenta for encapsulation. However, an increase in progesterone levels was found in the raw-dehydrated method placenta samples. This study reports, “The highest concentrations of hormones were found in raw placental tissue. The hormones were all sensitive to processing. The present study found an enormous hormone reduction through steaming and dehydration of placental tissue. It is most likely caused through denaturation of proteins after thermal processing [47]. Dehydration alone caused a minor hormone loss and even increased the concentration of progesterone” (Johnson et al. 2018).

The preparation methods for placenta ingestion vary widely, with some placenta encapsulators advertising “gentle steaming to retain beneficial hormones and nutrients,” while another popular method is to consume placenta raw in smoothie form over days and weeks postpartum. The 2018 published paper, Placentophagy Among Women Planning Community Births in the United States: Frequency, Rationale, and Associated Neonatal Outcomes, found that midwives are reporting that nearly half of women in their data collection study are consuming raw-dehydrated placenta pills (Benyshek et al. 2018).

References:

Benyshek DC, Cheyney M, Brown J, Bovbjerg ML. (2018). Placentophagy Among Women Planning Community Births in the United States: Frequency, Rationale, and Associated Neonatal Outcomes. Birth 00:1‐10.

Djiane J., Durand, P. (1977). Prolactin-Progesterone Antagonism in Self Regulation of Prolactin Receptors in the Mammary Gland. Nature 266:641-43.

Hale, T., Hartman, P. (2007). Textbook of Human Lactation. (1st edition). Amarillo, TX:Hale Publishing.

Johnson, S, Groten T., Pastuschek J., Rödelb. J., Sammer, U., Markert, U. (2018). Human Placentophagy: Effects of Dehydration and Steaming on Hormones, Metals and Bacteria in Placental Tissue. Placenta 67; 8 – 14.

Mohrbacher, N. (2010). Breastfeeding Answers Made Simple: A Guide for Helping Mothers. Hale Publishing.

Nursen Gurtunca, N., Sperling, M. (2017). Fetal and Neonatal Physiology. (Fifth Edition).

Riordan, J. (2005). Breastfeeding and Human Lactation. (3rd edition). Sudbury, MA:Jones and Bartlett.

Walker, M. (2017). Breastfeeding Management for the Clinician: Using the Evidence. (4th edition). Sudbury, MA: Jones and Bartlett.

World Health Organization (2015). Medical eligibility criteria for contraceptive use 5th ed. http://www.who.int/reproductivehealth/publications/family_planning/MEC-5/en/

Young, S., Gryder, L., Zava, D., Kimball, D., Benyshek, D. (2016). Presence and Concentration of 17 Hormones in Human Placenta Processed for Encapsulation and Consumption. Placenta 43:86‐89.

SCBC Mission Statement:

“To educate and empower women to breastfeed; to encourage breastfeeding-friendly attitudes, policies, and images in the community; to promote unity among breastfeeding professionals and advocates; and to increase public awareness of the value of breastfeeding.”

View Sonoma County Breastfeeding Coalition Website

SCBC History:

The Sonoma County Breastfeeding Coalition is a community organization formed in 1996. The coalition is supported by volunteer community members comprised of Physicians, Lactation Consultants (IBCLCs), Midwives, Nurses, Dietitians, La Leche League Leaders and breastfeeding supporters representing local WIC agencies, hospitals, health clinics and various community members.