- Email: [email protected]
Is the lactational amenorrhea method a part of natural family planning? Biology and policy
Labbok and Howie
longer lactational amenorrhea. These issues only served to reinforce the consensus among all speakers that the LAM must be incorporated more closely into current NFP programs throughout the world. It is important to recognize that breastfeeding, especially exclusive breastfeeding, has a profound effect on fertility and on the estrogenic changes that create the signs and symptoms used in various NFP methods. Lactation after menses has returned is not nearly as
December 1991 Am J Obstet Gynecol
protective against unplanned pregnancy. Better understanding of the fertility suppressive effects of lactation and its incorporation into NFP teaching could be part of the solution to this problem. The following articles and discussions explore these and related issues. It is hoped that the conclusions of this session will provide guidance for NFP policy makers and trainers in the introduction of NFP during breastfeeding.
Is the lactational amenorrhea method a part of natural family planning? Biology and policy Barbara A. Gross, PhD Westmead, Australia The lactational amenorrhea method is a natural method of family planning for women who breastfeed their infants. The underlying physiology results in a natural suppression of ovulation, and the concomitant infants. breastfeeding. This in addition to the infant's age amenorrhea, induced by exclusive (or almost exclusive) breastfeeding. of 6 months or less and specific feeding pattern are the parameters used to identify the possible return of fertility. fertility. The lactational amenorrhea method provides at least 98% protection against pregnancy. Data from a recent multicenter study of breastfeeding support the use of the lactational amenorrhea method as a natural family planning method. method. The lactational amenorrhea method can be incorporated into natural family planning programs and teaching. (AM J OSSTET GVNECOL 1991;165:2014-9.) 1991 ;165:2014-9.)
Key words: Natural family planning, breastfeeding, lactational amenorrhea method, postpartum infertility The natural child-spacing effect of breastfeeding has been long recognized to be associated with amenorrhea and the duration of breastfeeding, particularly full breastfeeding. Furthermore, in population studies only about 5% to 10% of women have been reported to become pregnant while in lactational amenorrhea. 6 This effect received little attention among populations where breastfeeding was not a common practice. However, the incidence and duration of breastfeeding have been changing in both developed and developing countries, particularly since the early 1970s. In developed countries there has been a return to breastfeeding, and well-educated mothers in the higher socioeconomic groups are more likely to breastfeed and breastfeed breast feed longer than those from the lower socioeconomic or imFrom the Endocrine Unit, Department of Medicine, Westmead Hospital. Reprint requests: Barbara A. Gross, PhD, Endocrine Unit, Department of Medicine, M edicine, Westmead Westmead Hospital, Westmead, New South Wales, 2145. Australia, 2145. 6/0/34381 610134381
2014
migrant groups.' groups.7 In some developing countries, particularly in the urban areas, the pattern is the opposite; the more highly educated are less likely to initiate breastfeeding or to breastfeed for only short periods. In rural areas breastfeeding is more prolonged, but there has been a suggestion of a decline in the initiation and duration of breastfeeding in many populations. Economic changes and recent programs for the promotion and support of breastfeeding are associated with abatement and reversal of the decline in many settings. The duration oflactational amenorrhea in urban and rural populations also differs markedly from country to country, with a range varying from 2 to 3 months up to 2 to 3 years. In many of these populations breastfeeding has provided the major control of fertility; it delays the return of bleeding/menstruation bleeding / menstruation and ovulation, but it does not permanently prevent pregnancy. The impact of a decline in the duration of breastfeeding and its concomitant effect on lactational amenorrhea, particularly in developing countries, has been high-
Is LAM a part of NFP? 2015
Volume 165 Number 6, Part 2
lighted by several writers. 8s For example, in Senegal, where the average duration of breastfeeding and lactational amenorrhea is 19 and 15 months, respectively, a 50% reduction in the duration of breastfeeding would require an increase in contraceptive use from 11 % to 35% to maintain current fertility rates. 9 Natural family planning programs and lactational infertility
Breastfeeding has not been recognized for its important natural effect on fertility or as a natural family planning (NFP) method in most NFP programs in spite of the knowledge presented above. Many NFP programs recognize a 7- to 12-week period of natural infertility after childbirth, which is extended by breastfeeding. This is based on studies of breastfeeding 10,• 11 II and enwomen in which basal body temperature lO dometrial biopsy l2 were used as indicators of the probability of ovulation preceding the first postpartum bleed. In these studies most of the women breastfed for 3 to 6 months, with the period of full (or exclusive) breastfeeding even shorter, and solid and liquid supplements (cereal and juice) were introduced as early as 3 to 6 weeks after delivery. 14 Studies by Gross and Eastman l3 and Brown et al. l4 compared mucus symptoms with serum levels of estrogens and progesterone or their urinary metabolites. They found longer periods of infertility associated with longer durations of full breastfeeding. These findings were incorporated into teaching programs associated with the ovulation method and the symptothermal methods developed in Australia. These programs suggest that couples begin observing and recording their signs of fertility from 3 to 5 weeks after delivery. If a couple wants an almost zero risk of pregnancy, they are often counseled to abstain from the seventh or tenth postpartum week until they have evidence of ovulation by a sustained thermal shift of at least 4 days, thus resulting in a long period of abstinence during a period of relative infertility. Another choice presented by some NFP programs is to wean the baby to facilitate the return of cyclicity and the application ofNFP. In other instances couples using NFP methods based on cervical mucus observations are instructed that they can be guided by their observations to determine the days of infertility and possible fertility and to apply the rules for avoiding pregnancy. The mucus signs can be confusing for some, however, and do not always reflect the underlying ovarian activity; signs may suggest ovulation when it is not occurring or fail to indicate ovulation when it does occur. This can result in unnecessary and prolonged abstinence, although this may be acceptable to a couple with a strong desire to avoid another pregnancy. At the same time, pregnancy is possible, although not probable. The short
duration of lactational amenorrhea along with a suggested high incidence of first ovulatory bleeds, in spite of low pregnancy rate, were the major influences on NFP programs of the 1970s. Essentially the western breastfeeding patterns of the 1970s forced on NFP teaching nonacceptance of lactational amenorrhea as a natural method of family planning. Teaching programs with this viewpoint have been extended to the developing countries, where there has been and still should be a reliance on lactational amenorrhea as an effective natural method of birth spacing but with some guidelines as suggested below. Lactational amenorrhea
The mechanism of lactational amenorrhea is still not well understood. Prolactin levels are elevated during pregnancy and continue to be elevated above normal prepregnancy levels during lactational amenorrhea, but they gradually return to normal as ovarian function l5 Prolactin levels increase in response to suckreturns. 15 ling and may be a marker of the altered hypothalamicpituitary axis or may have a direct action on fertility, perhaps at the level of the ovary. Ovulation is prevented or follicular development may be altered, resulting in deficient corpus luteum function, altered endometrium, and infertility. This inhibition of ovarian function can continue even after bleeding resumes, explaining in part the lower than expected pregnancy rate while breastfeeding continues. lS have shown that menses can More recent studies l515•- 18 be delayed on average for 7 to 9 months even in wellnourished western women. Table I summarizes Australian studies indicating the return of vaginal bleeding between 33 to 48 weeks (7V2 to 11 months) after delivery, with individual women resuming ovulation as early as 12 weeks and others delaying up to 2 years_ years. Twentyfive percent to 30% of the women resumed menstruation while fully breastfeeding, with varying frequency and duration of breastfeeding episodes. In other populations such as in Chile and Mexico, the duration of amenorrhea is shorter in spite of full breastfeeding of high frequency. In most of the recent studies, 25% to 30% of women have evidence of ovulation (as indicated by adequate levels of serum progesterone or urinary pregnanediol) before the first bleed, but many of these ovulations show evidence of inadequate luteal func17 Furthermore, the incidence of ovulatory first tion. l7 bleeds occurring during full breastfeeding and in the first 6 months has been shown to be low, with a suggested pregnancy risk of less than 2%.19 The lactational amenorrhea method
An individual couple can rely on breastfeeding to provide natural protection against pregnancy for at least 6 months, provided the mother has no return of
2016
Gross
December 1991 Am J Obstet Gynecol
l3 ) Table I. Duration of lactational amenorrhea (Australian studies, Gross and Eastman Eastman")
Year
1976-78
89
1976-80
29
1986-88
25
1987-89
16
1989-90
119
Weeks (mean ± SD)
Study population
41.3 ± 25.5 (5-120)* 48.4 ± 25.8 (14-105) 32.8 ± 16.1 16.1 (12-66.4) 43.3 ± 12.3 (21-66.5) 38.2 ± 38.4 «13->52)
Australia
Type
Study sponsor
Ford / Rockefeller
A.C.T.
Retrospective, Retros pective, cross-section Prospective
Sydney
Prospective
FHI
Sydney
Prospective
WHO
Sydney
Retrospective, last breastfed. breast fed child
WHO
Ford/Rockefeller Ford / Rockefeller
FHI, Family Health International; WHO, World Health Organization. Organization.
*Range in parentheses. parentheses. bleeding (ignoring any bleed for up to 56 postpartum days) and the baby is being fully, or almost fully, breastfed. These guidelines provide less than a 2% risk of unplanned pregnancy. The above statement is now often referred to as the Bellagio Consensus Statement. 19.20 19. 20 When put into practice, the statement defined the lactational amenorrhea method (LAM)-a natural method of family planning based on the lactational amenorrhea produced by the ovulation suppression effects of full breastfeeding during the first 6 months of life. This method can be illustrated by an algorithm, or decision tree, developed initially by Miriam Labbok21 (Fig. 1) and modified according to the results of the recent research that formed the basis of the Bellagio Consensus Statement. 22 The Bellagio Consensus Statement was issued from a meeting of 25 scientists in Bellagio, Italy, convened by Family Health International and the World Health Organization. The Consensus Statement's pregnancy rate of less than 2% was based on data from three prospective studies of pregnancies occurring during lactational amenorrhea and full breastfeeding breast feeding in the 19.. 20 This figure was then first 6 postpartum months. 19 supported by the calculation of the probability of pregnancy based on observed premenstrual ovulation rates during the first 6 months of lactation. The pregnancy rate was assumed to be 25% of the ovulation rate, although fecundity of ovulation during breastfeeding is thought to be much lower than 25%. With this high estimate for comparison, data from 10 small prospective studies (25 to 113 11 3 subjects) using hormonal evidence of returning ovulation gave estimated pregnancy rates up to 2.9%.20 2.9%"0 The Bellagio Consensus Statement indicates that if these guidelines are adhered to (i.e., (i.e ., LAM is used), then 98% to 100% of couples will have warning of impending ovulation and can then make a decision on an alternative method of family planning, including NFP. 19
Three-center breastfeeding/NFP study
Preliminary data from a three-center study of NFP and breastfeeding in the United Kingdom, Canada, and Australia are described in more detail in the another article in this issue (Kennedy et al.). Table II illustrates the mean days of first bleed, first ovulation, and average number of days of protection provided by the Bellagio guidelines. The mean day of first bleed was very similar in Australia and Canada (229.6 ± 112.9 and 221.04 ± 8S.5 88.5 days, respectively), and this was approximately 30 days longer than in the United Kingdom (19S.9 (198.9 ± 114.5 days). The average number of days of infertility provided by LAM/BelLAMlBellagio guidelines was 134, 132, and 112 days, respectively, for Australia, Canada, and the United Kingdom. In all cases in Australia, the last day of protection provided by the Bellagio guidelines preceded the estimated first day of ovulation. In one case the first "bleed" was actually 6 days of spotting. If the spotting were discounted, one adequate and normal ovulation preceded both the Bellagio cutoff the first bleed in one woman who was fully breastfeeding. In addition, the first ovulation was not always an adequate ovulation as defined by pregnanediol levels (i.e., >9 nmol/24 nmoll24 hr) or length of the luteal phase (~10 days), in that the risk of conception for anyone ovulation is only 25% or less, and the guidelines therefore provided even greater protection than predicted. In Canada, the mean first estimated day of ovulation as determined from the urinary estrogen peak was 227.6 ± 90.9 days, whereas the first ovulation with an adequate luteal phase was at 264.S 264.8 ± lOS 108 days. The range was wide, 60 to 405 and 94 to 494 days, respectively. The Australian data are not complete, but with the preliminary data as a base, the first ovulation occurred between 76 and 455 days, at a mean of237 of 237 days. In the Sydney study the earliest ovulation with an apparently adequate and normal-length luteal phase was
Is IS LAM a part of NFP?
Volume 165 Number 6, Part 2
2017
Ask the mother:
NO
Is your baby less than six months old?
YES HSher chhanclde of prelgnancby is infcred~sed. e s ou not re y on reast ee mg :::, alone. Use another family planning method, but continue to breastfeed j for the child's health. ,:,:
Are you amenorrheic? (no vaginal bleeding after 56 days postpartum) (2)
::.:.'::',!,
YES Are you fully or nearly fully breastfeeding your baby? (3)
::::::::::::::::::::::::::::::::::::::::::::::::::::,:::::::::::::::::::::::::::::::::::::::::::::::i::::::::::::::::::::::::::::::::::::::::::::::::::::J:!
NO
YES There is ONLY ABOUT A 2% CHANCE OF PREGNANCY; she does not need a complementary family planning method at this time.
Tell the mother: when the answer to anyone of these questions becomes NO, - - - - - - - -
I
.J
:::::::::::::::::::::::::::::::::::::::::::::::::::::<::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::Ji;
(I) It must be noted that these guidelines are conservative. Women who follow these guidelines after six months postpartum, or who have experienced only one vaginal bleed, may still have some decreased fertility if if the recommended optimal breastfeeding behaviors are followed. Furthermore, in many areas of the world, women may breastfeed for 18-24 months and remain amenorrheic for 12 months or more. These women may remain infertile for 12-15 months postpartum. (2) Spotting that occurs during the first 56 days is not considered to be menses. (3) "Full" breastfeeding includes exclusive or almost exclusive breastfeeding (occasional tastes of ritual foods or water), day and night, according to recommendations. "Nearly full" breastfeeding means that occasional nonbreast feeds are given.
Fig. 1. Use of LAM for child spacing during the first 6 postpartum months.
on day 76, in a woman who weaned her baby on postpartum day 63. These findings suggest that individual women should begin to use an alternative method of family planning, including NFP, once they begin supplements after 6 months during lactational amenorrhea, if they wish to avoid pregnancy. However, it is obvious from the data that many women will remain and!/ or anovulatory well beyond 6 months amenorrheic and or beyond the introduction of supplements (see Fig. 1). I). The shortest intervals between the Bellagio guidelines and the first ovulation in the Australian group were 8 and 15 days in two subjects who resumed bleeding while fully breastfeeding. As indicated above, 6 days of spotting heralded the ovulation for one woman and
1 day of bleeding and 3 days of spotting for another. The mean interval between the postpartum days by LAM to the first ovulation was 103 days (range, 8 to 272) and to the first normal/adequate ovulation, 134 11 to 311). days (range, II The appropriate use of LAM results in a 2% pregnancy rate. The use of NFP, particularly the cervical mucus methods, may assist a woman to recognize the pending follicular development and ovulation. In three Australian studies of cervical mucus observations during breastfeeding, breast feeding, no pregnancies occurred before the first bleed, whether the bleed occurred during full breastfeeding, during partial breastfeeding, or after weaning. Studies in Chile also indicate high effective-
2018
Gross
December 1991 Am J Obstet Gynecol
Table II. Mean number of days ± SD (range) to first bleed and ovulation and provided by Bellagio International! International Institute for Studies in Natural guidelines (LAM) protection (Family Health International/International Family Planning Multicentre Breastfeeding/Natural Family Planning Study) Country
N
First bleed
First ovulation
Bel/agio protection
Australia
25
Canada
25
237 ± 105.4 (76t-455) 228 ± 91 (60-405)
United Kingdom
25
230 ± 112.9 (84-465)* 221 ± 88.5 (68-356) 199 ± 114.5 (71 -470) (71-470)
134 ± 38.6 (55-183) 132 ± 36.4 (64-183) 112 ± 34.4 (54-183)
*Range in parentheses. tOvulated before first bleed but after weaning at 63 postpartum days.
Table III. Comparison of number of days of abstinence required by NFP methods with number of days protection provided by Bellagio guidelines or LAM
Country
Australia Canada England TOTAL T01AL
Abstinence during Bel/agio protection
Bel/agio Bellagio protection (mean no. of days) *
Mean no. of dayst
134 (55-183)§ 83)§ (55-1 132 (64-183) 112 (54-183) 126 (54-183)
17 (0-69) 25 (0-97) 21 (0-60) 21 (0-97)
I
Mean % of days:t days:f:
11.7 (0-37.7) 17.3 (0-58.4) 17.6 (0-43.4) (0-43 .4) 15.5 (0-58.4)
*Includes the first 42 postpartum days for all women. tThe maximum possible number of days of abstinence is 183 - (42 + 14) = 127 days, where 14 is the number of days required after day 42 to describe the infertile pattern. *Greatest possible proportion is 69.4%. §Range in parentheses.
ness of the ovulation method, particularly during full breastfeeding and during the first 6 months. 2233 One of the disadvantages of using cervical mucus observations to predict ovulation may be the inability to recognize the infertile days because of the continuous and confusing mucus patterns that result in prolonged abstinence. 14. 24·26 An interesting comparison of the number of days of abstinence imposed by NFP observations with those imposed by LAM can be made by using the data from the multicenter study described in the article by Kennedy et al. in this issue (Table III). As shown in Table II, the number of days of protection provided by the Bellagio guidelines was on average 126 days (range 55 to 183). The calculated number of days of abstinence that would have been required based on mucus observations (and basal body temperature in some cases) during this period of LAM use ranged from 0 to 97 days (mean, 21 days), with up to 58.4% of these days actually requiring abstinence (with a possible maximum of 69%). By using NFP, 20 of 75 couples would have had to abstain for more than 20% of the days indicated as infertile by the LAM criteria. By contrast, 30 of 75 couples identified less than 10% of the infertile days as requiring abstinence; their fer-
tility signs were closely related to the infertility indicated by LAM. It could be argued that the frequency of intercourse is naturally low during this time,27 time!7 but this could also be due to lack of confidence in their infertility based on NFP signs, aa low libido, fatigue, or other reasons. The point of the analysis is that LAM can minimize the time required for abstinence and result in a low risk of pregnancy. Future research
Many questions remain. What are the limitations of LAM? Can the 2% risk of pregnancy with LAM be further reduced? Is spotting a warning of impending ovulation for those likely to be at risk of becoming pregnant? Can a previous lactation experience be used as a guide? It is also important to define what constitutes full breastfeeding. Is there a minimum number of breastfeeds by day and/or by night? Is there a minimum duration of a suckling episode or total suckling during a day? Is there a maximum interval between feeds? Is this more important by day or by night? Is there a minimum intensity of suckling? Does supplementation and pacifier use in small amounts or after suckling af-
Volume 165 Number 6, Part 2
feet fect the physiologic impact? How much other food (liquid or solid), by quantity or frequency or caloric content, can be included as almost fully breastfeeding? How much do early postpartum factors in the establishment of breastfeeding affect subsequent fertility? What characteristics of the infant, the mother, and the breastfeeding patterns affect lactational infertility? Are there environmental factors that influence breastfeeding patterns or physiologic responses? Policy questions A number of policy questions have yet to be resolved, resolved. Should LAM be included in NFP training and teaching programs? What adjustments to teaching need to be made both to support breastfeeding as well as to initiate NFP during breastfeeding? What education and motivation of teachers are needed to increase confidence in LAM? What ancillary education programs are needed to inform teachers and clients of the factors that maximize the infertility effects of breastfeeding? What support is needed for clients to benefit from the LAM? How should NFP methods methods be applied after return of menstruation?
Conclusions and recommendations
The natural protection afforded by LAM should be incorporated into the teaching of NFP. It can provide couples with security in their postpartum infertility, minimize the abstinence that might otherwise be necessary as a result of confusing mucus or basal body temperature observations, and allow couples to enjoy their new infant and renew their relationship. The interface with NFP is obvious. The woman can still be aware of and observe symptoms that can alert her to the possibility of approaching fertility. More detailed observations and charting should begin at the end of the natural protection provided by LAM, and application of the appropriate method of NFP should then be made to avoid pregnancy. The studies carried out in collaboration with Family Health International were under the direction of Kathy Kennedy and with collaborating scientists Dr. Suzanne Parenteau-Carreau, Serena, Montreal, Canada, and Dr. Anna Flynn, University of Birmingham, United Kingdom. Urinary estrogen and pregnanediol assays were carried out by Joanne Holmes and Gillian Barker under the direction of Professor James Brown at the Department of Obstetrics and Gynecology, Royal Women's Hospital, Carlton, Melbourne, Australia, and also the help of Sheila Kippley (Couple to Couple League International, Inc., Cincinnati, Ohio). REFERENCES 1. Gross BA. The hormonal and ecological correlates of lacFertil 1981 ;26:209. ;26:209. tational infertility. Int] Ferti!
Is LAM a part of NFP?
2019
2. Billings EL, Donovan A. The Billings method. Melbourne: Anne O'Donovan, 1982. 3. Australian Council of Natural Family Planning. Teacher training manual, 1986. 4. Flynn AM, Brooks M. M. AA manual of natural family planning. London: George Allen and Unwin, 1984. 5. Gross BA. Unpublished memo. American Council of Natural Family Planning, 1978. 6. Buchanan R. Breastfeeding-aid to infant health and fertility control. Population report, series]. series J. 1975;4:49. 7. Hitchcock NE, Coy]F. Infant-feeding practices in Western Australia and Tasmania: a joint survey, 1984-1985. 1984-1985. Med] Aust 1988;148:114. 8. Thyma P. P. Fertile and infertile days of married life: the double check method. Fall River, Massachusetts: 1975. 9. Bongaarts], Potter R. Fertility, biology and behavior: an analysis of the proximate determinants. New York: Academic Press, 1983. 10. Cronin T]. TJ. Influence of lactation upon ovulation. Lancet 1968;2:422. 1968;2 :422 . 11. Pascal]. Pascal J. Some aspects of postpartum physiology contribution of the basal body temperature and its application to birth regulation [MD thesis]. University of Nancy, France, 1969. 12. Perez A, Vela P, Masnick GS, Potter RG. RG. First ovulation after childbirth: the effect of breast feeding. feeding. AM] OBSTET GYNECOL GVNECOL 1972;114:1041. CJ. Prolactin and the return of ovu13. Gross BA, Eastman C]. lation in breastfeeding women. ] Biosoc Sci Suppl 1985;9:25. 14. Brown ]B, Harrison P, Smith MA. A study of returning fertility after childbirth and during lactation by measurement of urinary oestrogen and pregnanediol excretion and cervical mucus production. ]J Biosoc Sci Suppl 1985;9:5. CJ. Effect of breastfeeding status on 15. Gross BA, Eastman C]. prolactin secretion and resumption of menstruation. Aust Med] 1983;1:313. 16. Gray RH, Campbell 0, Apelo R, et al. Risk of ovulation during lactation. Lancet 1990;335:25. 17. Howie PW, McNeilly AS, Houston M], MJ, Cook S, Boyle H. Fertility after childbirth: infant feeding patterns, basal Prl Pri levels and postpartum ovulation. Clin Endocrinol 1982;17:315. 18. McNeilly AS, Glasier AF, Howie PW, et al. Fertility after childbirth: pregnancy associated with breastfeeding. Clin Endocrinol 1983; 18: 167. EndocrinoI1983;18:167. 19. Family Health International. Consensus statement, breastfeeding as a family planning method. Lancet 1988;2:1204. 20. Kennedy KI, Rivera R, McNeilly AS. Consensus statement on the use of breastfeeding as a family planning method. Contraception 1989;39:477. 21. Labbok MH. Breastfeeding and contraception. N Engl] Engl J Med 1983;308:51. breastfeeding feeding in family 22. Labbok MH, et al. Guidelines for breast planning and child survival programs. Washington, DC: International Institute for Studies in Natural Family Planning, 1990. 23. Perez A, Labbok M, Barker D, Gray R. R. Use-effectiveness of the ovulation method initiated during postpartum breastfeeding. Contraception 1988;38:499. 24. Gross BA. Breastfeeding and the return to fertility. In Rev NFP 1984;8:102. 25. Hatherley Ll. Lactation and postpartum infertility: the use-effectiveness of natural family planning after term pregnancy. Clin Reprod Ferti! Fertil 1985;3:319. 26. Parenteau-Carreau S. The return of fertility in breastfeeding women. lnt Rev NFP 1984;8:34. Int 27. Gross BA. Breastfeeding and natural family planning. lnt ] Ferti! Fertil Suppl 1988:24.
longer lactational amenorrhea. These issues only served to reinforce the consensus among all speakers that the LAM must be incorporated more closely into current NFP programs throughout the world. It is important to recognize that breastfeeding, especially exclusive breastfeeding, has a profound effect on fertility and on the estrogenic changes that create the signs and symptoms used in various NFP methods. Lactation after menses has returned is not nearly as
December 1991 Am J Obstet Gynecol
protective against unplanned pregnancy. Better understanding of the fertility suppressive effects of lactation and its incorporation into NFP teaching could be part of the solution to this problem. The following articles and discussions explore these and related issues. It is hoped that the conclusions of this session will provide guidance for NFP policy makers and trainers in the introduction of NFP during breastfeeding.
Is the lactational amenorrhea method a part of natural family planning? Biology and policy Barbara A. Gross, PhD Westmead, Australia The lactational amenorrhea method is a natural method of family planning for women who breastfeed their infants. The underlying physiology results in a natural suppression of ovulation, and the concomitant infants. breastfeeding. This in addition to the infant's age amenorrhea, induced by exclusive (or almost exclusive) breastfeeding. of 6 months or less and specific feeding pattern are the parameters used to identify the possible return of fertility. fertility. The lactational amenorrhea method provides at least 98% protection against pregnancy. Data from a recent multicenter study of breastfeeding support the use of the lactational amenorrhea method as a natural family planning method. method. The lactational amenorrhea method can be incorporated into natural family planning programs and teaching. (AM J OSSTET GVNECOL 1991;165:2014-9.) 1991 ;165:2014-9.)
Key words: Natural family planning, breastfeeding, lactational amenorrhea method, postpartum infertility The natural child-spacing effect of breastfeeding has been long recognized to be associated with amenorrhea and the duration of breastfeeding, particularly full breastfeeding. Furthermore, in population studies only about 5% to 10% of women have been reported to become pregnant while in lactational amenorrhea. 6 This effect received little attention among populations where breastfeeding was not a common practice. However, the incidence and duration of breastfeeding have been changing in both developed and developing countries, particularly since the early 1970s. In developed countries there has been a return to breastfeeding, and well-educated mothers in the higher socioeconomic groups are more likely to breastfeed and breastfeed breast feed longer than those from the lower socioeconomic or imFrom the Endocrine Unit, Department of Medicine, Westmead Hospital. Reprint requests: Barbara A. Gross, PhD, Endocrine Unit, Department of Medicine, M edicine, Westmead Westmead Hospital, Westmead, New South Wales, 2145. Australia, 2145. 6/0/34381 610134381
2014
migrant groups.' groups.7 In some developing countries, particularly in the urban areas, the pattern is the opposite; the more highly educated are less likely to initiate breastfeeding or to breastfeed for only short periods. In rural areas breastfeeding is more prolonged, but there has been a suggestion of a decline in the initiation and duration of breastfeeding in many populations. Economic changes and recent programs for the promotion and support of breastfeeding are associated with abatement and reversal of the decline in many settings. The duration oflactational amenorrhea in urban and rural populations also differs markedly from country to country, with a range varying from 2 to 3 months up to 2 to 3 years. In many of these populations breastfeeding has provided the major control of fertility; it delays the return of bleeding/menstruation bleeding / menstruation and ovulation, but it does not permanently prevent pregnancy. The impact of a decline in the duration of breastfeeding and its concomitant effect on lactational amenorrhea, particularly in developing countries, has been high-
Is LAM a part of NFP? 2015
Volume 165 Number 6, Part 2
lighted by several writers. 8s For example, in Senegal, where the average duration of breastfeeding and lactational amenorrhea is 19 and 15 months, respectively, a 50% reduction in the duration of breastfeeding would require an increase in contraceptive use from 11 % to 35% to maintain current fertility rates. 9 Natural family planning programs and lactational infertility
Breastfeeding has not been recognized for its important natural effect on fertility or as a natural family planning (NFP) method in most NFP programs in spite of the knowledge presented above. Many NFP programs recognize a 7- to 12-week period of natural infertility after childbirth, which is extended by breastfeeding. This is based on studies of breastfeeding 10,• 11 II and enwomen in which basal body temperature lO dometrial biopsy l2 were used as indicators of the probability of ovulation preceding the first postpartum bleed. In these studies most of the women breastfed for 3 to 6 months, with the period of full (or exclusive) breastfeeding even shorter, and solid and liquid supplements (cereal and juice) were introduced as early as 3 to 6 weeks after delivery. 14 Studies by Gross and Eastman l3 and Brown et al. l4 compared mucus symptoms with serum levels of estrogens and progesterone or their urinary metabolites. They found longer periods of infertility associated with longer durations of full breastfeeding. These findings were incorporated into teaching programs associated with the ovulation method and the symptothermal methods developed in Australia. These programs suggest that couples begin observing and recording their signs of fertility from 3 to 5 weeks after delivery. If a couple wants an almost zero risk of pregnancy, they are often counseled to abstain from the seventh or tenth postpartum week until they have evidence of ovulation by a sustained thermal shift of at least 4 days, thus resulting in a long period of abstinence during a period of relative infertility. Another choice presented by some NFP programs is to wean the baby to facilitate the return of cyclicity and the application ofNFP. In other instances couples using NFP methods based on cervical mucus observations are instructed that they can be guided by their observations to determine the days of infertility and possible fertility and to apply the rules for avoiding pregnancy. The mucus signs can be confusing for some, however, and do not always reflect the underlying ovarian activity; signs may suggest ovulation when it is not occurring or fail to indicate ovulation when it does occur. This can result in unnecessary and prolonged abstinence, although this may be acceptable to a couple with a strong desire to avoid another pregnancy. At the same time, pregnancy is possible, although not probable. The short
duration of lactational amenorrhea along with a suggested high incidence of first ovulatory bleeds, in spite of low pregnancy rate, were the major influences on NFP programs of the 1970s. Essentially the western breastfeeding patterns of the 1970s forced on NFP teaching nonacceptance of lactational amenorrhea as a natural method of family planning. Teaching programs with this viewpoint have been extended to the developing countries, where there has been and still should be a reliance on lactational amenorrhea as an effective natural method of birth spacing but with some guidelines as suggested below. Lactational amenorrhea
The mechanism of lactational amenorrhea is still not well understood. Prolactin levels are elevated during pregnancy and continue to be elevated above normal prepregnancy levels during lactational amenorrhea, but they gradually return to normal as ovarian function l5 Prolactin levels increase in response to suckreturns. 15 ling and may be a marker of the altered hypothalamicpituitary axis or may have a direct action on fertility, perhaps at the level of the ovary. Ovulation is prevented or follicular development may be altered, resulting in deficient corpus luteum function, altered endometrium, and infertility. This inhibition of ovarian function can continue even after bleeding resumes, explaining in part the lower than expected pregnancy rate while breastfeeding continues. lS have shown that menses can More recent studies l515•- 18 be delayed on average for 7 to 9 months even in wellnourished western women. Table I summarizes Australian studies indicating the return of vaginal bleeding between 33 to 48 weeks (7V2 to 11 months) after delivery, with individual women resuming ovulation as early as 12 weeks and others delaying up to 2 years_ years. Twentyfive percent to 30% of the women resumed menstruation while fully breastfeeding, with varying frequency and duration of breastfeeding episodes. In other populations such as in Chile and Mexico, the duration of amenorrhea is shorter in spite of full breastfeeding of high frequency. In most of the recent studies, 25% to 30% of women have evidence of ovulation (as indicated by adequate levels of serum progesterone or urinary pregnanediol) before the first bleed, but many of these ovulations show evidence of inadequate luteal func17 Furthermore, the incidence of ovulatory first tion. l7 bleeds occurring during full breastfeeding and in the first 6 months has been shown to be low, with a suggested pregnancy risk of less than 2%.19 The lactational amenorrhea method
An individual couple can rely on breastfeeding to provide natural protection against pregnancy for at least 6 months, provided the mother has no return of
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Gross
December 1991 Am J Obstet Gynecol
l3 ) Table I. Duration of lactational amenorrhea (Australian studies, Gross and Eastman Eastman")
Year
1976-78
89
1976-80
29
1986-88
25
1987-89
16
1989-90
119
Weeks (mean ± SD)
Study population
41.3 ± 25.5 (5-120)* 48.4 ± 25.8 (14-105) 32.8 ± 16.1 16.1 (12-66.4) 43.3 ± 12.3 (21-66.5) 38.2 ± 38.4 «13->52)
Australia
Type
Study sponsor
Ford / Rockefeller
A.C.T.
Retrospective, Retros pective, cross-section Prospective
Sydney
Prospective
FHI
Sydney
Prospective
WHO
Sydney
Retrospective, last breastfed. breast fed child
WHO
Ford/Rockefeller Ford / Rockefeller
FHI, Family Health International; WHO, World Health Organization. Organization.
*Range in parentheses. parentheses. bleeding (ignoring any bleed for up to 56 postpartum days) and the baby is being fully, or almost fully, breastfed. These guidelines provide less than a 2% risk of unplanned pregnancy. The above statement is now often referred to as the Bellagio Consensus Statement. 19.20 19. 20 When put into practice, the statement defined the lactational amenorrhea method (LAM)-a natural method of family planning based on the lactational amenorrhea produced by the ovulation suppression effects of full breastfeeding during the first 6 months of life. This method can be illustrated by an algorithm, or decision tree, developed initially by Miriam Labbok21 (Fig. 1) and modified according to the results of the recent research that formed the basis of the Bellagio Consensus Statement. 22 The Bellagio Consensus Statement was issued from a meeting of 25 scientists in Bellagio, Italy, convened by Family Health International and the World Health Organization. The Consensus Statement's pregnancy rate of less than 2% was based on data from three prospective studies of pregnancies occurring during lactational amenorrhea and full breastfeeding breast feeding in the 19.. 20 This figure was then first 6 postpartum months. 19 supported by the calculation of the probability of pregnancy based on observed premenstrual ovulation rates during the first 6 months of lactation. The pregnancy rate was assumed to be 25% of the ovulation rate, although fecundity of ovulation during breastfeeding is thought to be much lower than 25%. With this high estimate for comparison, data from 10 small prospective studies (25 to 113 11 3 subjects) using hormonal evidence of returning ovulation gave estimated pregnancy rates up to 2.9%.20 2.9%"0 The Bellagio Consensus Statement indicates that if these guidelines are adhered to (i.e., (i.e ., LAM is used), then 98% to 100% of couples will have warning of impending ovulation and can then make a decision on an alternative method of family planning, including NFP. 19
Three-center breastfeeding/NFP study
Preliminary data from a three-center study of NFP and breastfeeding in the United Kingdom, Canada, and Australia are described in more detail in the another article in this issue (Kennedy et al.). Table II illustrates the mean days of first bleed, first ovulation, and average number of days of protection provided by the Bellagio guidelines. The mean day of first bleed was very similar in Australia and Canada (229.6 ± 112.9 and 221.04 ± 8S.5 88.5 days, respectively), and this was approximately 30 days longer than in the United Kingdom (19S.9 (198.9 ± 114.5 days). The average number of days of infertility provided by LAM/BelLAMlBellagio guidelines was 134, 132, and 112 days, respectively, for Australia, Canada, and the United Kingdom. In all cases in Australia, the last day of protection provided by the Bellagio guidelines preceded the estimated first day of ovulation. In one case the first "bleed" was actually 6 days of spotting. If the spotting were discounted, one adequate and normal ovulation preceded both the Bellagio cutoff the first bleed in one woman who was fully breastfeeding. In addition, the first ovulation was not always an adequate ovulation as defined by pregnanediol levels (i.e., >9 nmol/24 nmoll24 hr) or length of the luteal phase (~10 days), in that the risk of conception for anyone ovulation is only 25% or less, and the guidelines therefore provided even greater protection than predicted. In Canada, the mean first estimated day of ovulation as determined from the urinary estrogen peak was 227.6 ± 90.9 days, whereas the first ovulation with an adequate luteal phase was at 264.S 264.8 ± lOS 108 days. The range was wide, 60 to 405 and 94 to 494 days, respectively. The Australian data are not complete, but with the preliminary data as a base, the first ovulation occurred between 76 and 455 days, at a mean of237 of 237 days. In the Sydney study the earliest ovulation with an apparently adequate and normal-length luteal phase was
Is IS LAM a part of NFP?
Volume 165 Number 6, Part 2
2017
Ask the mother:
NO
Is your baby less than six months old?
YES HSher chhanclde of prelgnancby is infcred~sed. e s ou not re y on reast ee mg :::, alone. Use another family planning method, but continue to breastfeed j for the child's health. ,:,:
Are you amenorrheic? (no vaginal bleeding after 56 days postpartum) (2)
::.:.'::',!,
YES Are you fully or nearly fully breastfeeding your baby? (3)
::::::::::::::::::::::::::::::::::::::::::::::::::::,:::::::::::::::::::::::::::::::::::::::::::::::i::::::::::::::::::::::::::::::::::::::::::::::::::::J:!
NO
YES There is ONLY ABOUT A 2% CHANCE OF PREGNANCY; she does not need a complementary family planning method at this time.
Tell the mother: when the answer to anyone of these questions becomes NO, - - - - - - - -
I
.J
:::::::::::::::::::::::::::::::::::::::::::::::::::::<::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::Ji;
(I) It must be noted that these guidelines are conservative. Women who follow these guidelines after six months postpartum, or who have experienced only one vaginal bleed, may still have some decreased fertility if if the recommended optimal breastfeeding behaviors are followed. Furthermore, in many areas of the world, women may breastfeed for 18-24 months and remain amenorrheic for 12 months or more. These women may remain infertile for 12-15 months postpartum. (2) Spotting that occurs during the first 56 days is not considered to be menses. (3) "Full" breastfeeding includes exclusive or almost exclusive breastfeeding (occasional tastes of ritual foods or water), day and night, according to recommendations. "Nearly full" breastfeeding means that occasional nonbreast feeds are given.
Fig. 1. Use of LAM for child spacing during the first 6 postpartum months.
on day 76, in a woman who weaned her baby on postpartum day 63. These findings suggest that individual women should begin to use an alternative method of family planning, including NFP, once they begin supplements after 6 months during lactational amenorrhea, if they wish to avoid pregnancy. However, it is obvious from the data that many women will remain and!/ or anovulatory well beyond 6 months amenorrheic and or beyond the introduction of supplements (see Fig. 1). I). The shortest intervals between the Bellagio guidelines and the first ovulation in the Australian group were 8 and 15 days in two subjects who resumed bleeding while fully breastfeeding. As indicated above, 6 days of spotting heralded the ovulation for one woman and
1 day of bleeding and 3 days of spotting for another. The mean interval between the postpartum days by LAM to the first ovulation was 103 days (range, 8 to 272) and to the first normal/adequate ovulation, 134 11 to 311). days (range, II The appropriate use of LAM results in a 2% pregnancy rate. The use of NFP, particularly the cervical mucus methods, may assist a woman to recognize the pending follicular development and ovulation. In three Australian studies of cervical mucus observations during breastfeeding, breast feeding, no pregnancies occurred before the first bleed, whether the bleed occurred during full breastfeeding, during partial breastfeeding, or after weaning. Studies in Chile also indicate high effective-
2018
Gross
December 1991 Am J Obstet Gynecol
Table II. Mean number of days ± SD (range) to first bleed and ovulation and provided by Bellagio International! International Institute for Studies in Natural guidelines (LAM) protection (Family Health International/International Family Planning Multicentre Breastfeeding/Natural Family Planning Study) Country
N
First bleed
First ovulation
Bel/agio protection
Australia
25
Canada
25
237 ± 105.4 (76t-455) 228 ± 91 (60-405)
United Kingdom
25
230 ± 112.9 (84-465)* 221 ± 88.5 (68-356) 199 ± 114.5 (71 -470) (71-470)
134 ± 38.6 (55-183) 132 ± 36.4 (64-183) 112 ± 34.4 (54-183)
*Range in parentheses. tOvulated before first bleed but after weaning at 63 postpartum days.
Table III. Comparison of number of days of abstinence required by NFP methods with number of days protection provided by Bellagio guidelines or LAM
Country
Australia Canada England TOTAL T01AL
Abstinence during Bel/agio protection
Bel/agio Bellagio protection (mean no. of days) *
Mean no. of dayst
134 (55-183)§ 83)§ (55-1 132 (64-183) 112 (54-183) 126 (54-183)
17 (0-69) 25 (0-97) 21 (0-60) 21 (0-97)
I
Mean % of days:t days:f:
11.7 (0-37.7) 17.3 (0-58.4) 17.6 (0-43.4) (0-43 .4) 15.5 (0-58.4)
*Includes the first 42 postpartum days for all women. tThe maximum possible number of days of abstinence is 183 - (42 + 14) = 127 days, where 14 is the number of days required after day 42 to describe the infertile pattern. *Greatest possible proportion is 69.4%. §Range in parentheses.
ness of the ovulation method, particularly during full breastfeeding and during the first 6 months. 2233 One of the disadvantages of using cervical mucus observations to predict ovulation may be the inability to recognize the infertile days because of the continuous and confusing mucus patterns that result in prolonged abstinence. 14. 24·26 An interesting comparison of the number of days of abstinence imposed by NFP observations with those imposed by LAM can be made by using the data from the multicenter study described in the article by Kennedy et al. in this issue (Table III). As shown in Table II, the number of days of protection provided by the Bellagio guidelines was on average 126 days (range 55 to 183). The calculated number of days of abstinence that would have been required based on mucus observations (and basal body temperature in some cases) during this period of LAM use ranged from 0 to 97 days (mean, 21 days), with up to 58.4% of these days actually requiring abstinence (with a possible maximum of 69%). By using NFP, 20 of 75 couples would have had to abstain for more than 20% of the days indicated as infertile by the LAM criteria. By contrast, 30 of 75 couples identified less than 10% of the infertile days as requiring abstinence; their fer-
tility signs were closely related to the infertility indicated by LAM. It could be argued that the frequency of intercourse is naturally low during this time,27 time!7 but this could also be due to lack of confidence in their infertility based on NFP signs, aa low libido, fatigue, or other reasons. The point of the analysis is that LAM can minimize the time required for abstinence and result in a low risk of pregnancy. Future research
Many questions remain. What are the limitations of LAM? Can the 2% risk of pregnancy with LAM be further reduced? Is spotting a warning of impending ovulation for those likely to be at risk of becoming pregnant? Can a previous lactation experience be used as a guide? It is also important to define what constitutes full breastfeeding. Is there a minimum number of breastfeeds by day and/or by night? Is there a minimum duration of a suckling episode or total suckling during a day? Is there a maximum interval between feeds? Is this more important by day or by night? Is there a minimum intensity of suckling? Does supplementation and pacifier use in small amounts or after suckling af-
Volume 165 Number 6, Part 2
feet fect the physiologic impact? How much other food (liquid or solid), by quantity or frequency or caloric content, can be included as almost fully breastfeeding? How much do early postpartum factors in the establishment of breastfeeding affect subsequent fertility? What characteristics of the infant, the mother, and the breastfeeding patterns affect lactational infertility? Are there environmental factors that influence breastfeeding patterns or physiologic responses? Policy questions A number of policy questions have yet to be resolved, resolved. Should LAM be included in NFP training and teaching programs? What adjustments to teaching need to be made both to support breastfeeding as well as to initiate NFP during breastfeeding? What education and motivation of teachers are needed to increase confidence in LAM? What ancillary education programs are needed to inform teachers and clients of the factors that maximize the infertility effects of breastfeeding? What support is needed for clients to benefit from the LAM? How should NFP methods methods be applied after return of menstruation?
Conclusions and recommendations
The natural protection afforded by LAM should be incorporated into the teaching of NFP. It can provide couples with security in their postpartum infertility, minimize the abstinence that might otherwise be necessary as a result of confusing mucus or basal body temperature observations, and allow couples to enjoy their new infant and renew their relationship. The interface with NFP is obvious. The woman can still be aware of and observe symptoms that can alert her to the possibility of approaching fertility. More detailed observations and charting should begin at the end of the natural protection provided by LAM, and application of the appropriate method of NFP should then be made to avoid pregnancy. The studies carried out in collaboration with Family Health International were under the direction of Kathy Kennedy and with collaborating scientists Dr. Suzanne Parenteau-Carreau, Serena, Montreal, Canada, and Dr. Anna Flynn, University of Birmingham, United Kingdom. Urinary estrogen and pregnanediol assays were carried out by Joanne Holmes and Gillian Barker under the direction of Professor James Brown at the Department of Obstetrics and Gynecology, Royal Women's Hospital, Carlton, Melbourne, Australia, and also the help of Sheila Kippley (Couple to Couple League International, Inc., Cincinnati, Ohio). REFERENCES 1. Gross BA. The hormonal and ecological correlates of lacFertil 1981 ;26:209. ;26:209. tational infertility. Int] Ferti!
Is LAM a part of NFP?
2019
2. Billings EL, Donovan A. The Billings method. Melbourne: Anne O'Donovan, 1982. 3. Australian Council of Natural Family Planning. Teacher training manual, 1986. 4. Flynn AM, Brooks M. M. AA manual of natural family planning. London: George Allen and Unwin, 1984. 5. Gross BA. Unpublished memo. American Council of Natural Family Planning, 1978. 6. Buchanan R. Breastfeeding-aid to infant health and fertility control. Population report, series]. series J. 1975;4:49. 7. Hitchcock NE, Coy]F. Infant-feeding practices in Western Australia and Tasmania: a joint survey, 1984-1985. 1984-1985. Med] Aust 1988;148:114. 8. Thyma P. P. Fertile and infertile days of married life: the double check method. Fall River, Massachusetts: 1975. 9. Bongaarts], Potter R. Fertility, biology and behavior: an analysis of the proximate determinants. New York: Academic Press, 1983. 10. Cronin T]. TJ. Influence of lactation upon ovulation. Lancet 1968;2:422. 1968;2 :422 . 11. Pascal]. Pascal J. Some aspects of postpartum physiology contribution of the basal body temperature and its application to birth regulation [MD thesis]. University of Nancy, France, 1969. 12. Perez A, Vela P, Masnick GS, Potter RG. RG. First ovulation after childbirth: the effect of breast feeding. feeding. AM] OBSTET GYNECOL GVNECOL 1972;114:1041. CJ. Prolactin and the return of ovu13. Gross BA, Eastman C]. lation in breastfeeding women. ] Biosoc Sci Suppl 1985;9:25. 14. Brown ]B, Harrison P, Smith MA. A study of returning fertility after childbirth and during lactation by measurement of urinary oestrogen and pregnanediol excretion and cervical mucus production. ]J Biosoc Sci Suppl 1985;9:5. CJ. Effect of breastfeeding status on 15. Gross BA, Eastman C]. prolactin secretion and resumption of menstruation. Aust Med] 1983;1:313. 16. Gray RH, Campbell 0, Apelo R, et al. Risk of ovulation during lactation. Lancet 1990;335:25. 17. Howie PW, McNeilly AS, Houston M], MJ, Cook S, Boyle H. Fertility after childbirth: infant feeding patterns, basal Prl Pri levels and postpartum ovulation. Clin Endocrinol 1982;17:315. 18. McNeilly AS, Glasier AF, Howie PW, et al. Fertility after childbirth: pregnancy associated with breastfeeding. Clin Endocrinol 1983; 18: 167. EndocrinoI1983;18:167. 19. Family Health International. Consensus statement, breastfeeding as a family planning method. Lancet 1988;2:1204. 20. Kennedy KI, Rivera R, McNeilly AS. Consensus statement on the use of breastfeeding as a family planning method. Contraception 1989;39:477. 21. Labbok MH. Breastfeeding and contraception. N Engl] Engl J Med 1983;308:51. breastfeeding feeding in family 22. Labbok MH, et al. Guidelines for breast planning and child survival programs. Washington, DC: International Institute for Studies in Natural Family Planning, 1990. 23. Perez A, Labbok M, Barker D, Gray R. R. Use-effectiveness of the ovulation method initiated during postpartum breastfeeding. Contraception 1988;38:499. 24. Gross BA. Breastfeeding and the return to fertility. In Rev NFP 1984;8:102. 25. Hatherley Ll. Lactation and postpartum infertility: the use-effectiveness of natural family planning after term pregnancy. Clin Reprod Ferti! Fertil 1985;3:319. 26. Parenteau-Carreau S. The return of fertility in breastfeeding women. lnt Rev NFP 1984;8:34. Int 27. Gross BA. Breastfeeding and natural family planning. lnt ] Ferti! Fertil Suppl 1988:24.