A Look at Lactation Amenorrhea Method and Ecological Breastfeeding

Leah Jacobson, MA, IBCLC

Lactation Amenorrhea Method (LAM); History, Development, and Definition

Although the Lactation Amenorrhea Method has only relatively recently received the attention of researchers and the medical community, it appears that women have instinctively understood the connection between breastfeeding and decreased fertility for thousands of years.  While there is a very limited amount of information on ancient understandings of fertility, and, much of the information that has survived is mostly conjecture, historians widely agree that our ancestors understood the inverse connection of lactation with fertility.

The ancient Roman doctor, Soranus, speaks of extended breastfeeding in Roman women, and recommended that mothers not consider weaning their babies until eighteen to twenty-four months to take full advantage of the child-spacing abilities of breastfeeding. 1

It is also recorded in numerous texts that royal women in many different times and societies employed the use of wet nurses for their own children so that they would experience a quicker return to fertility. “From the eleventh century onwards, most aristocrats handed their infants over to the wet nurse, which contributed to a steep growth in fertility among aristocratic women, as they were now denied the contraceptive qualities of lactation. From the twelfth century all children born to the French royal family would be denied their mother’s breast (until Marie Antoinette bravely defied tradition). Partly this was to ensure the birth of plenty of children (potential heirs), but it may also have been done to provide the husband with access to his wife’s sexual favours, it being commonly believed that sex during lactation was an abomination of some sort and could even damage the child by polluting the breast milk.” 2

Ancient Egyptian wet nurse contracts were commonly drawn up for a period of two years, reflecting a longer societal norm of breastfeeding than we typically see today. Historians have projected this longer period of breastfeeding as indicative of the ancient people’s understanding of reduced fertility while nursing. 3

The earliest known research to be conducted on the connection between breastfeeding and amenorrhea came from Dr. Leonard Remfry. His study was first published in an English medical journal in 1895. “While others were aware in a general way that breastfeeding spaced babies, he [Dr. Remfry] was apparently the first to analyze and quantify this phenomenon. His finding that only “six percent” of breastfeeding mothers in his study became pregnant before their first menstruation is still significant. Actually, he rounded up; the actual percentage of mothers who became pregnant while still in amenorrhea was 5.77 percent.” 4   The work of Dr. Remfry around the turn of the century would begin a measured growth of medical interest on the subject, but would unfortunately be interrupted and slowed down by the sudden debut and popularity of artificial baby food “formulas” that hit the markets widely in the 1920’s. 5

Research on lactation amenorrhea continued to gradually come forward and by the 1970’s there were approximately fifty studies that had been conducted around the concept of LAM. Author Sheila Kippley provides a wonderful review of all the known research done on lactation amenorrhea prior to 1972 in her Review of Breastfeeding Infertility Research up to 1972.

Almost all of the studies conducted prior to 1972 produced results that supported Remfry’s findings of delayed fertility with breastfeeding mothers, but to varying degrees and with no clear connection as to causation.  Kippley points out in her review that there were not clear definitions of key terms in place to provide a consistent starting point for each of these studies.  She felt that as our culture moved more towards the promotion of bottle-feeding and away from breastfeeding that our very definitions and practices of breastfeeding also changed.

For example, a woman breastfeeding in the 1960’s may have considered herself to be “exclusively breastfeeding” if she was not feeding her baby solid foods yet, although she may have been using a pacifier and supplementing nursing with formula or water.  A woman who was “exclusively breastfeeding” sixty years earlier would have probably had her baby at the breast whenever the child cried out for comfort, using no other means of pacifying or supplementation.

These key fundamental differences in terminology and methodology could cause major discrepancies among the results of the research on lactation and amenorrhea. Kippley decided it was time to establish criteria for researchers to follow when defining the type of breastfeeding they were looking at in their studies.  She set out to differentiate between “ecological breastfeeding” and “cultural breastfeeding” practices.

Ecological Breastfeeding Research

In the 1960’s, when breastfeeding rates in the United States were at an all-time low of only 20% 7, John and Sheila Kippley reinvigorated the discussion about lactational amennorhea with their publication of Breastfeeding and Natural Child Spacing 8.  In this book they set forth six key criteria for “Ecological Breastfeeding”, a term that refers to the pattern described as “natural mothering” in their text.  More or less, women who fit the “natural mothering” categories met the following criteria;

  1. No pacifiers used
  2. No bottles used
  3. No solids or liquids for first 5 months
  4. No feeding schedule other than baby’s
  5. Presence of night feedings
  6. Presence of lying-down nursing for naps and night feedings

The Kippleys knew from their own experiences that the type and frequency of breastfeeding greatly affected the length of amenorrhea. With their first study they sought to establish significant values for the behavioral differences of breastfeeding mothers. This study was conducted in 1971 and reinforced the overall findings on lactational amenorrhea from Dr. Remfry’s study, conducted nearly 75 years earlier. He had predicted a pregnancy rate of 6% for women who were breastfeeding and remained amenorrheic in the first six months. The Kippleys lowered this by a point by predicting a 5% rate for breastfeeding amenorrheic women. Their own study sample provided a 100% efficacy for Ecological Breastfeeding, but they did not feel that was a number indicative of the entire population and conservatively predicted a 5% efficacy for the population at large.  They stated their sample was not representative of the general population as their sample had a higher number of “natural mothers” than normal. They accounted for the “cultural breastfeeding” practices that so many nursing mothers succumbed to at the time with their 5% prediction of efficacy.

In their study, they separated all the nursing mothers into two categories; 1) cultural breastfeeders, and 2) natural mothering, or Ecological Breastfeeders.  The women who were considered cultural breastfeeders were women who subscribed to standard cultural practices at that time; i.e. pacifiers, swings, nursing schedules, separate sleeping locations, etc.  This group did not supplement with any juice, formula, or water and only fed their babies breast milk.  The natural mothers adopted a more hands on approach to nurturing their babies, currently encapsulated by the idea of “attachment parenting” 9.  These mothers wore their babies, seldom put them down, slept with them, nursed on cue from the baby, and did not depend on feeding schedules or pacifiers.

The results of their study showed that for the first group of mothers, the mean length of time for amenorrhea lasted for 11.6 months. For the second group which met all the criteria for EB, the mean length of time for amenorrhea was 14.6 months, a 43% increase. They hypothesized that the suckling action of the baby and the number of times in a day that the baby suckled contributed to the lengthened amenorrhea.

The Development of LAM

The Kippley’s hypothesis about lengthened amenorrhea, their Ecological Breastfeeding criteria, and the standards for instruction on EB (the precursor to LAM) remained largely unchanged or challenged until 1988, when the Bellagio Consensus came forward.

In August of 1988, “an interdisciplinary international group of researchers in the area of lactational infertility gathered with the purpose of coming to a consensus about the conditions under which breastfeeding can be used as a safe and effective method of family planning. The consensus of the group was that the maximum birth spacing effect of breastfeeding is achieved when a mother “fully” or nearly fully breastfeeds and remains amenorrheic. When these two conditions are fulfilled, breastfeeding provides more than 98% protection from pregnancy in the first six months.” 10

Thus the Lactation Amenorrhea Method was defined by the international medical community with three main criteria, “1) amenorrhea, 2) full or nearly full breastfeeding, and 3) first six months postpartum. The guidelines for LAM include the advice that women who no longer meet these three criteria, or no longer wish to use LAM, should immediately initiate the use of another family planning method if they wish to avoid pregnancy”. 11

With a basic definition and guidelines of the method now in place, researchers now had a statement and number to challenge in their own studies.  “Subsequent to the 1988 Consensus meeting, several studies designed expressly to test this Consensus were conducted. To review the results of these studies as well as other relevant research, the experts [again] gathered at Bellagio in 1995. They concluded that the Bellagio Consensus clearly has been confirmed.” 12

Ecological Breastfeeding and LAM; Is there even a difference?

In 1992 the Kippleys, who by now had founded the non-profit agency International Couple to Couple League to promote Natural Family Planning and Ecological Breastfeeding, introduced a new set of standards for Ecological Breastfeeding (EB).  They contended that the efficacy of LAM would never be as high as the efficacy of EB due to the constraints of “cultural restrictions” on breastfeeding;  i.e. use of pacifiers, bottles, early supplementation, babysitters, and strict schedules. Unless these cultural practices are clearly eliminated by including clear criteria for women to follow, the full effectiveness of lactational amenorrhea will not be realized.

The Kippleys released these updated Seven Standards of Ecological Breastfeeding to serve as a clear guide for women seeking the full benefits of lactation amenorrhea:

  1. Do exclusive breastfeeding for the first six months of life; don’t use other liquids and solids.
  2. Pacify your baby at your breasts.
  3. Don’t use bottles and pacifiers.
  4. Sleep with your baby for night feedings.
  5. Sleep with your baby for a daily-nap feeding.
  6. Nurse frequently day and night, and avoid schedules.
  7. Avoid any practice that restricts nursing or separates you from your baby.

The Kippleys maintained that using EB can dramatically increase the amount of time a woman remains amenorrheic and created guidelines to help women in using their method past the six months that LAM covers. LAM includes only three criteria;

  1. Amenorrhea
  2. Full or nearly full breastfeeding, and
  3. First six months postpartum

As a Board Certified Lactation Consultant, I feel that if LAM was expanded to more explicitly include some of the EB criteria, it would see an even higher level of success in naturally spacing pregnancies, and that the length of time for this success rate would increase as well.   In the following section we will look at the biological reasons that EB could extend LAM’s efficacy and make it even more successful.

Efficacy of LAM vs. Ecological Breastfeeding; Biological Considerations

LAM has been proven repeatedly by top researchers to be a very successful method for naturally spacing children in the first 6 months postpartum. However, if one looks closely at the studies that experienced the highest levels of efficacy for LAM, one will notice that these are the studies that incorporate more of the Seven Standards outlined above.  I believe there is a very simple biological explanation for this; prolactin production.

Prolactin is a hormone that stimulates the production of milk in the breast. It is produced by the pituitary gland in response to stimulation of the nipple. Levels of prolactin spike in the mother’s body in response to the suckling stimulus of the baby at her breast. “Prolactin levels go down in between nursings and rise during nursing. More frequent nursing causes higher baseline levels of prolactin, and therefore more milk-making potential in frequent feeders.” 13

Another function of prolactin is to suppress ovulation in women, thereby making them infertile. “High prolactin will decrease FSH (follicle stimulating hormone) levels. This leads to irregular ovulation and irregular menstrual periods, or no periods at all – amenorrhea.” 14

Women who follow the Kippley’s EB standards and offer their breast to their baby several times throughout the day never experience a significant drop-off of prolactin levels. Therefore FSH will not be able to reach a level high enough to release an egg for ovulation to occur. However, under the current LAM guidelines, a woman following the method could regularly go 5-6 hours between feedings and allow her prolactin levels to fall off completely. When this happens, her body could begin producing FSH and eventually begin releasing eggs. She may be “fully” breastfeeding, meaning the baby is not eating anything other than her breast milk, but her body is experiencing hormonal shifts that it interprets as weaning; thus leading to a premature return to fertility.

The use of “baby nesting” practices, as outlined by Healthy Children Project instructor Barbara O’Connor, RN, IBCLC, BSN leads mothers to separate themselves from close contact with their babies throughout the day. We leave our babies in manmade “nests” such as car seats, swings, strollers, and cribs for many hours in between nursings. These current parenting practices, which the Kippleys call “cultural barriers to breastfeeding”, greatly reduce the levels of prolactin in our systems and lead to earlier returns of fertility for many women. By specifying the behaviors that both encourage more prolactin production (suckling, frequency, contact) and behaviors that inhibit its production (separation, “baby nesting”), LAM would become an even more effective method.

LAM vs. Other Birth Control Methods

            LAM has been proven to be very effective, but how does it compare to other methods of birth control?  According to Planned Parenthood, our nation’s largest birth control distributor, LAM is 92-98% effective in preventing pregnancy for the first 6 months.15  This is just as effective as the birth control shot (Depro-Provera), hormonal birth control pills, the birth control ring (NuvaRing), and the birth control patch (Ortho-Evra). In fact, Planned Parenthood rates LAM as only a few percentage points behind permanent birth control practices such as vasectomy and tubal ligations.

Planned Parenthood has in the past been infamously skeptical of natural birth spacing methods and natural fertility awareness; however, the evidence in support of LAM is so overwhelming that even they have chosen to include it on their website and give information about its many benefits to women.

Cultural and Religious Perspectives of LAM; Ethical Considerations

LAM has many advantages in being adopted by women worldwide as their preferred method of family planning.

First of all, it is a free method and poverty would not affect a woman’s ability to use LAM. Others methods of birth control can cost hundreds of dollars over the course of a year, and with no greater efficacy than LAM. The financial arguments in favor of LAM are strong when one also considers the cost of formula and increased medical bills associated with artificial feedings. These costs can add up to thousands of dollars for one child in a year. 16

Secondly, there are obvious benefits to both the baby and mother physically. These benefits have been well documented and women are becoming increasingly aware of the “breast is best” ideology. With reports possibly linking breastfeeding to lowered levels of breast and ovarian cancers, many more women seem interested in the benefits of breastfeeding not only for their child’s health, but also their own.17 More women are opting to initiate breastfeeding in the United States as they become better educated about the benefits of breastfeeding.18

And finally, there are really no religious stigmas or teachings that oppose the practice of breastfeeding. In fact, the Catholic Church has actually issued statements about a “maternal obligation” for mothers to breastfeed their babies if possible and upholds the practice as one of the greatest gifts women can give to humanity.19

On the other hand, there are several Christian, Judaic, and Islamic groups that directly oppose the use of artificial contraception for birth control, making LAM an even more attractive option for many as nothing else is required to space pregnancies naturally.

Culturally there is a great variance in acceptance of artificial birth control around the world. In a study conducted in 2004 within the Latin American population, it was found that Latina women were very uncomfortable with emergency contraception being offered to them. They cited religious reasons for not wanting to take this type of birth control.20

Ethnic Chinese women expressed similar sentiments in a 2001 study when presenting for an abortion and questioned about using birth control. They reported not wanting a “bad reputation” for using hormonal contraceptives. 21

Another study found that Latina women in Texas doubted the safety of oral contraceptives and were unlikely to seek their use.22

Artificial contraceptives are often not the first choice for many women worldwide, for a variety of reasons. With proper promotion, education, and support many women worldwide can experience those same contraceptives benefits of LAM without the negative side-effects and negative feelings associated with artificial contraceptives.


LAM has been proven through evidence-based research to be at least 98% effective in preventing pregnancy the first six months postpartum. I do feel that the method, while very effective, is not currently clearly defined enough for the purposes of education about its use and implementation of it by nursing mothers.

I recommend exploring the Standards of Ecological Breastfeeding and adding the additional criteria that are proven to have a significant effect to the Lactational Amenorrhea Method. With further modifications and research, I am hopeful we will see the method extended for an even longer period of time and that more women will feel confident in their use of this method.  I feel that the development of this method for family planning has not yet reached its end and that we may see more changes to the history of LAM’s development and use.


  1. Bowman A.K., Garnsey P., Rathbone D. (2000). The Cambridge ancient history: The High Empire, A.D. 70-192. Cambridge.
  2. Doolan, Paul. (2008, December). History Today. London: Nursing Times, Vol. 58, Iss. 12; pg. 24, 7 pgs.
  3. Same as 2.
  4. Kippley, Sheila. (2008). Remfry’s Article 185. Retrieved January 28th, 2011 from NFP and More website; Lactation Infertility Research. http://www.nfpandmore.org/remfrys_article_1895.pdf
  5. Mead Johnson Nutritional Division. (1980). Retrieved February 1st, 2011 from the Baby Bottle Museum website, History of the Baby Bottle.


  1. Kippley, Sheila. (1974). Retrieved January 15th, 2011 from NFP and More website; Lactation Infertility Research. http://www.nfpandmore.org/reviewbreastfeeding.shtm
  2. La Lech League International. (2010). Retrieved from the LLLI website January 28th, 2011). LLLI; History. http://www.llli.org/LLLIhistory.html
  3. Kippley, J., S. (1969) Breastfeeding and Natural Child Spacing. Cincinnati, Ohio, K Publishers.
  4. Sears, (2011). Retrieved from the Ask Dr. Sears website on February 6th, 2011. http://www.askdrsears.com/html/10/t130300.asp
  5. Kennedy K. I., Riveran R., McNeilly A.S.. (1989, May).  Consensus statement on the use of breastfeeding as a family planning method. Contraception . Vol. 39, Issue 5, Pages 477-496.
  6. Linkages Project. (2011). Retrieved February 3rd, 2011 from the Linkages Project website; Consensus Statement: Lactational Amenorrhea Method for Family Planning. http://www.linkagesproject.org/LAMCD/publicationsconE.htm
  7. Same as 11.
  8. Healthy Children Project. (2011). Center for Breastfeeding; Lactation Counselor Training Program Manual. E Sandwich, MA. USA. Pg. 14.
  9. Advanced Fertility Center of Chicago. (2011). Retrieved from their website on February 7th,  2011.  http://www.advancedfertility.com/bromocriptine-prolactin-ovulation.htm
  10. Planned Parenthood. (2005, April). Retrieved January 29th, 2011 , which cites: Hatcher, RA; Trussel J, Stewart F, et al. (2000). Contraceptive Technology (18th ed.). New York: Ardent Media.  “Comparison of Effectiveness”. http://www.plannedparenthood.org/birth-control-pregnancy/birthcontrol/effectiveness.htm
  11. Ball T.M, & Wright A., (1999, April). Health Care Costs of Formulafeeding in the First Year of Life.  Pediatrics, Vol. 103. No. 4. pp. 870-876.
  12. American Institute for Cancer Research, 2010. Recommendations for Cancer Prevention, Retrieved Aug. 3, 2012. http://www.aicr.org/reduce-your-cancer-risk/recommendations-for-cancer-prevention/recommendations_09_breastfeeding.html
  13. La Lech League International. (2010). Retrieved from the LLLI website January 28th, 2011). LLLI; History. http://www.llli.org/LLLIhistory.html
  14. Virtue, Rev. William D., (1995). Mother and Infant, Pontifica Studiorum Universitas, Rome.
  15. Romo L.F, Berenson A.B.,Wu Z.H. (2004, March). The role of misconceptions on Latino women’s acceptance of emergency contraceptive pills.  Original Research Article, Contraception, Volume 69, Issue 3, Pages 227-235.
  16. Wiebe E.R., Sent L., Fong S., Chan J. (2002, February). Barriers to use of oral contraceptives in ethnic Chinese women presenting for abortion. Contraception, Volume 65, Issue 2, Pages 159-163.
  17. Grossman D., & Fernández L., & Hopkins K., & Amastae J., & Potter J.E. (2010, March). Perceptions of safety of oral contraceptives among a predominantly Latina population in Texas. Contraception, Volume 81, Issue 3, Pages 254-260.

Can Breastfeeding Really Help You Space Your Children?

Leave a Reply