The natural family planning-lactational amenorrhea method interface: Observations from a prospective study of breastfeeding users of natural family planning

The natural family planning-lactational amenorrhea method interface: Observations from a prospective study of breastfeeding users of natural family planning Kathy I. Kennedy, MS,. Suzanne Parenteau-Carreau, MS: Anna Flynn, MD,c Barbara Gross, PhD/ James B. Brown, PhD: and Cynthia Visness' Durham, North Carolina, Serena and Ontario, Canada, Birmingham, England, and Westmead and Melbourne, Australia Methods of natural family planning are sometimes difficult for women to use during lactation. When this is so, the lactational amenorrhea method may prove useful. Researchers agree that a fully breastfeeding woman who is amenorrheic is 98% protected from pregnancy for up to 6 months after delivery. The fertility status of 74 users of natural family planning during the time they would have been protected by the lactational amenorrhea method is examined. Underlying hormonal profiles show that there was little ovarian activity during this time. Eight ovulatory events occurred during the period of protection by the lactational amenorrhea method, of which four fulfilled minimum criteria for adequacy; there were no pregnancies during this period. However, some women did report experiencing fertile mucus symptoms during this time that were often unrelated to estrogen production. Using the lactational amenorrhea method rather than natural family planning allows them to avoid unnecessary abstinence. (AM J OBSTET GYNECOL GVNECOL 1991 ;165:2020-6.)

Key words: Natural family planning, breastfeeding, lactational amenorrhea method, postpartum infertility

Lactational amenorrhea method (LAM) is the informed use of lactational amenorrhea, during full or breastfeeding, as a means of avoiding pregnearly full bredstfeeding, nancy for up to 6 months after delivery.! delivery. 1 It is based on the Bellagio Consensus Statement, a summary of 13 studies from eight countries that concluded that "breastfeeding provides more than 98% protection from pregnancy during the first 6 months postpartum if the mother is 'fully' or nearly fully breastfeeding and has not yet experienced vaginal bleeding after the 56th day postpartum."2.3 Natural family planning (NFP) methods have been adapted for use during lactation and have been taught and used successfully by various NFP programs around

Supported by funds from Family Health International (FHI) and the Institute for Reproductive Health, through their cooperative agreements with Agency for International Development (AID). The views refiect expressed herein are those of the authors and do not necessarily reflect those of FHI, the Institute, or A.I.D. I . Kennedy, MS, Family Health InternaReprint requests: Kathy I. tional, P.O. Box 13950, Research Triangle Park, Durham, NC 27709. aFamily Health International, Durham, North Carolina. "Family bSerena and Ontario, Canada. 'Serena 'Department of Obstetrics and Gynecology, Birmingham Maternity Hospital, Birmingham, England. dEndocrine Unit, Department of Medicine, Westmead Hospital, New South Wales, Australia. 'Royal Women's Hospital, University of Melbourne, Victoria, Australia. tralia. 6/0/34380

2020

the world. However, unlike the usual cervical response to estrogen production in the normally cycling, nonlactating woman, cervical mucus production during lactation does not always reflect the underlying ovarian physiology'" 55 During lactation, cervical mucus production is usually a consequence of estrogen secretion. However, when mucus with fertile characteristics is produced in the absence of ovarian activity and hormone production, the use of NFP during breastfeeding can be difficult. If this unexplained mucus production is irregular, establishment of a basic infertile pattern could be especially difficult and could require several weeks of abstinence following NFP rules. The frequency of unexplained fertile-type mucus production during lactation is not known, although it was observed, with confirmation by ovarian ultrasonography, in 18 breastfeeding women, (not randomly selected): and a similar case is also described herein. selected)" Consequently, it is of interest to know whether the use of LAM for up to 6 postpartum months by experienced NFP users would be useful, especially in terms of the amount of postpartum abstinence recommended by NFP that could be averted by using LAM. A study of the use of the symptothermal method (STM) by breastfeeding women was conducted through Serena, Montreal, Canada; Westmead Hospital in Sydney, Australia; and the Birmingham Maternity Hospital in England. The purpose of the study was to evaluate the use of STM by breastfeeding women to learn

NFP-LAM interface

Volume 165 Number 6, Part 2

2021

Table I. Duration of natural protection, days of recommended abstinence, and days with fertile mucus symptoms during LAM protection (N = 25 per center) Montreal Mean

No. of days of LAM protection No. of days during LAM protection in which STM recommended abstinence % of days during LAM protection in which STM recommended abstinence No. of days during LAM protection with fertile mucus symptoms % of days during LAM protection with fertile symptoms

132 25

17% 21 15%

I

Sydney

Range

Mean

64-183 0-97

134 17

0%-58% 0-1l5 0-115

0%-67%

12% 15 10%

I

Birmingham

1 Range

Total

1 Range

Range

Mean MeanT

Range

Mean MeanT

Range

55-183 0-69

112 21

54-183 0-60

126 21

54-183 0-97

0%-38% 0-65 0%-38%

18%

0%-43%

16 14%

0-68 0%-58%

16% 17 13%

0%-58% 0-1l5 0-115

0%-67%

whether it is biologically reasonable to use STM during breastfeeding to predict the recovery of fertility, and to determine whether NFP symptoms are related to the hormonal pattern that is presumed to cause them. This study permitted three types of observations related to the interface between NFP methods and LAM: (I) (1) a description of the mucus symptoms and estrogen production during the period of natural protection as defined by LAM; (2) an example of the kind of woman who would benefit by substituting LAM for NFP in the first 6 postpartum months; and (3) a description of the single unplanned pregnancy and how it is related to both LAM and STM.

longer, the ovulation was called "adequate" (or sometimes "possibly adequate" because the criteria for adequacy are the bare minimum values associated with normal cycling). Follicular development is considered to be present when the concentration of total urinary estrogens is ~ 15 Ilg/24 J.Lg/24 hr, particularly when it is part of a rising J.Lg/24 hr pattern. (Concentrations between 10 and 15 Ilg/24 could possibly reflect follicular activity when they are part of a pattern of increasing estrogen concentration, and would be expected in only a minority of women with very low baseline levels of estrogen.)

Method Twenty-five experienced STM users were recruited in each center. The women were normal and healthy, as were their babies; they intended to use STM to prevent pregnancy and to breastfeed for at least 6 months. Each day they completed a detailed two-page diary sheet that covered questions about infant feeding and about their natural fertility symptoms (qualities of cervical mucus, basal body temperature, and, for some women, the position of the cervix). The women also collected a timed urine sample every day from which levels of estrogen 6 and progesterone progesterone"7 metabolites were measured and from which the estimated day of peak estrogen production was determined by the laboratory at the Royal Womens' Hospital of the University of Melbourne, Australia. One woman was not included from parts of the analysis because there were too many missing urine samples to draw conclusions about her fertility status. "Ovulation" is said to have occurred if a rise in total urinary estrogen above 10 Ilg/24 J.Lg/24 hr is seen, followed by a rise in pregnanediol glucuronide to at least 4.5 Ilg/24 J.Lg/24 hr. The ovulation was called "inadequate" if pregnanediol glucuronide excretion was low (~4.5 but <9.0 Ilg/24 J.Lg/24 hr) and/or if the luteal phase lasted less than 10 days. If pregnanediol excretion was greater (~9.0 Ilg/24 J.Lg/24 hr) and if the luteal phase was 10 days or

The duration of natural protection from LAM. According to LAM a breastfeeding breast feeding woman can experience up to 183 days (6 months) of natural protection from pregnancy as long as she remains amenorrheic and breastfeeds her baby without supplements. When the LAM guidelines were applied in this study, the period of natural protection ranged from 54 to 183 days, averaging 4.1 months (Table I). In each study center some women did experience the maximum number of days of LAM protection (four, six, and two women in Montreal, Sydney, and Birmingham, respectively). The women in all three centers usually began supplements by the end of the sixth month, and the duration of LAM protection ended at the commencement of supplementation in 16, 13, and 16 women in Montreal, Sydney, and Birmingham, respectively. Abstinence by use of STM during LAM protection. During this period of natural protection according to LAM, days 0 to 97 would have been days in which abstinence was recommended if the STM was used correctly. Expressed in percents, during 0% to 58% of the time that was infertile according to LAM, abstinence was recommended according to STM (Table I). Mucus symptoms during LAM protection. We also see in Table I that from 0% to 67% of the days of natural LAM protection are days on which fertile mucus symptoms occurred. Some of the women reported

Results and explanation

2022

Kennedy et al.

December 1991 Am] Am J Obstet Gynecol

• 5 ,t <5

1

.0 '0 ,t

• )5 R [

G H A )0 H

o

,t

2~ .. 25

L

G L U 20 • C U R

o

N 1 ~ ...• I

., .,

D

10 lOt,

IJ.

..+ .

t • + +

H

..

..

t + t +

.f.. . .

H.. H· +tt .. .. ... ++ t· + t .. ..f. •ttt+-Ht .. +-+- ...... t t+t .... +;t ~:t t+ t ... +++ • ++ ttl.... t..... .. ++ tttt+++t+t .. tt+.tt+ttt+t+++t++t+-t-+t++t++t" .... -++t+t+ .... t+t++-+- ..... +++t+t+++.t++ ..t . t t t t .... +- • •+ftf.+• t .. t+ +++++ +.+++ t +t++ +-+t+- .... +++++++ ..... +++++++++++t+++ •• +++t+++++H-++++-++++++++".+-"'.f.+-+ +-++++t+.++-+f.t++ +H-t+-+++++ ...... + t ...... ........-+++ +-+- .... t.++ ft. ++t++ttt+t++t-+ t tt+-+. ++-+++++ +++ ... .. +++"".f. +-ft. +++... ·Ht . .....+++ . t+-tt+-+-+-+-++-+- ••• t .. +Ht +++ ....... f ..... "''' ++ .....+-tt +++...... t-+t'" ++++ +++ ... +-+t ............. t ........ ++-+-+ ++ ... ++ H· ++ +++ t ... t+ ... ..tt+++ ...t++ ++ t+ +++.f.++'" ..++++ .... +-+- t t ++ ++tH++++ ++.f.tH·t+-t+++++-ttt+++++f+++++t+++t++++tt+++t++t++++++++++++-+++++ + f f t t ..... •• +-+-.+.+-+-" +-+ +tttH'+H++t+.H.+t+++ttH·+t++t+ .. tH·t+++t+++t++t++++f.+++++~+++. ..+- tt+++-++++++++ +-.+-+-+t+- •• "."" .+.ttf++- t +t H· ..t ++ +t++ t+++"t ftft++++-+++"'+"'''''' t++++t++++++++++ +++ ..t ++ .f-.+++++++ -tt+++++++ ++ +t +++ ++ ........+- +++ -t++ +++ ++ t+ .... ..... .... +ft+ +t++++ tt+t t

5 ..

..f.

..... ..t .... .... t ...· .. ft+.t+.H-++H·" +++-+++

".+.+-.+.+"+""

t.

t.+""'+++"''' ........ ..

0" o ,

I

- ... __ - - ----- - - - +- - -- ---t----- +-- - - - --+--- - +--- -- -- ---- t ------t -- - -- -- ---- ..+-t-----

___- + ___ -_ __ t'0

~O 50

60

70 10

BO 80

90

-+----

t.. ..

- - - -- ---+-- ... -- --- .. ----- -- ---. - - -. - - - ---+ +----- ----+ --- ... --- ---- ... - ----... ---

- - - - - ... - - - - -----t - -+ - -- -- ---- -- -- ..... -- -- ---- -- -- -- ... ---

100

110

120

1)0

1'0 140

1~0 150

160

170 110

1BO 180

190

DAY AATtIH O"Y POSTP POSTPARTUM UOTr::: »arr:

_06) 08S .... o ~ISSIHG HISSIHG V,a.,t.UES V .... LUtS OR W[R.[ OllT OtJT 406) OBS n II~? OR. W(R.[

or

IU.NGt R..WGE

1616 161.6 OBS

HIDDEH HlOO[H

The Lactational Amenorrhea Method (LAM) is a natural method of family planning for breastfeeding women. It should be incorporated into Natural Family Planning (NFP) programs and teaching.

Fig. 1. Distribution of number of days between end of Bellagio protection (LAM) and the first day of ovulation as estimated from urinary pregnanediol levels. (Note that ovulation may not have been normal ovulation with adequate luteal phase.) phase.) (Illustration provided by Georgetown University.)

no fertile mucus during this period. Some of the reports of fertile-type mucus were accurate reflections of the underlying ovarian activity, and they preceded the first ovulations, albeit usually inadequate ones. In other cases, however, the mucus symptoms were deceptive, portraying fertility when there was in reality no estrogen production! In this situation NFP can be very difficult to use (see following case description). In Fig. I progesterone production-the hormonal consequence of ovulation-is reported as micromoles of urinary pregnanediol per 24 hours. The four potentially adequate cycles can be seen easily as the four episodes in which pregnanediol rose above the minimum value associated with normal luteinization f,Lmo1l24 hr). (9 fJ..mo1l24 Only one of these four potentially adequate episodes (the first) reflects a significant amount of pregnanediol excretion. In this case, during the 2 weeks immediately before ovulation, the woman breastfed breast fed her baby as seldom as five times in a 24-hour period, with interepisode

1/2 hours. She also reported that intervals as long as 991/2 the baby had colic colic and that the breastfeeds were therefore brief. During about half of this period, she breastfed only during the day and not at all at night. She had also given her baby a bottle of milk or formula for 3 days in the week before ovulation. Since she had not yet given the baby supplemental food every day for 7 consecutive days, she was not yet categorized in this study as "supplementing"; however, this pattern would be considered less than full breastfeeding. The three remaining potentially adequate cycles in the lower panel of Fig. 1I were each characterized by a IO-day luteal phase. phase. The likelihood is very low that such a brief luteal phase could have characterized a cycle capable of sustaining a pregnancy. In Fig. 2 these three cyles with IO-day lO-day luteal phases are counted as "adequate" in an inverse life table depiction of the percentages ovulatory during the period of LAM protection because there is a slim chance that the event was fully fertile.

NFP-LAM interface 2023

Volume 165 Number 6, Part 2

100 90

BO 80 bll

,§ ·il

'"r
~

0

c~

u

70 60

8B

50

~

40

C u

30

0..

20

0

..... '0 u

~tl p."

10 0 0

4

12

8

16

20

24

2B 28

Weeks Postpartum First Ovulation First Adequate Ovulation Fig. 2. Time to first evidence of ovulation and first adequate ovulation during LAM protection in all three centers, N = 74.

Altogether, eight out of 74 women for whom hormone data are available (11 %) experienced symptoms of ovulation. In four of these cases the ovulation could possibly have been adequate (5%), although in only one case was the luteal phase greater than 10 days (1 %). The life table rates for women experiencing the first ovulation by the sixth month of LAM protection (0.257) and the first possible adequate ovulation (0.139) are higher than the absolute percents mentioned above (11 % and 5%) because most women were censored from the life table during the fifth and sixth postpartum months; at this point they were regularly supplementing the baby's breastmilk diet with other foods and therefore had ceased to be protected by LAM because they were no longer nearly fully breastfeeding. To estimate the probability of pregnancy, both the absolute and life table percentages of women ovulating must be multiplied by a factor of 0.25 or lower. Since in even normally cycling, nonlactating women, no more than 25% will conceive during any given cycle,"'o cycle,s.lo the maximum 6-month life table pregnancy rate falls between 1.25% and 6.23%. It would be prudent, however, to remember that only one ovulation was characterized by strong evidence that it was normal; therefore we would expect a much lower pregnancy rate than this range suggests.

What kind of STM user would most benefit by using LAM? It seems intuitively obvious that any woman who is knowledgeable about LAM, who plans to exclusively breastfeed her baby for at least 6 months, and who makes an informed choice to use LAM is a good candidate for the method. We would like to give a cautionary note; if her previous breastfeeding experience reflects an early return of fertility, she may wish to take this into account in her informed choice. STM users, particularly those for whom STM rules recommend a great deal of abstinence even during amenorrhea and exclusive breastfeeding, might be especially happy to substitute LAM for STM for 6 months. For example, one woman in the Montreal center contributed most of the reported days of fertile type mucus, and she was definitely infertile during her entire 6 months of LAM protection. Fig. 3 displays her mucus symptoms and her estrogen profile for this period. This woman experienced persistent mucus, which she, as an experienced NFP user, perceived to be fertile, whereas her estrogen production remained persistently flat. She may have been an ideal candidate for LAM, since the proper use of STM required abstinence for more than a third of these days. The unplanned pregnancy vis-Ii-vis vis-a.-vis LAM and STM. This study was not designed to yield an effectiveness

2024

Kennedy et al.

December 1991 Am J Obstet Gynecol

Lubricalivo Lubricative

Wei Wet MoisVDamp MoisuDamp

Slicky Sticky

Sensation

Not Dry Dry

i~~~~~~~~~~~~~~~ l

Sireichy Siringy Stringy

Sirelchiness Stretchlness

Sticky Sketchy No stretch slrelch

Abundanl Abundant Normal

]- - - --------A Am mo o-u un nt--

Nothing Cloar

Cloudy

Opaque Shiny

Nothing

J---:-l----

11O~oO'~·o 'j 1

Appearance

_

~

= ~~;~~~~E~":ns_ Tolal Urinary Estrogens Ilg/24 hrs, I

o04~O~-------W---------8-0--------1-0~O~==~-=1~20~--~~-14-0----~~1-6~O-=------1~80 4~O~-------6-0---------8-0---------10~O~~~~=12=O~--~~-14~O~--==~-16-O~~--~-1--80

Days Postpartum Fig. 3. Mucus symptoms and estrogen levels for mother No. No. 22 22,, Canadian center. (Illustration provided by Georgetown University.)

rate for either LAM or STM. The women in the study were actively using STM as it is taught by their respective centers. One unplanned pregnancy occurred in a woman at the Montreal center at the end of her sixth postpartum month during full breastfeeding (Fig. (Fig. 4). At the estimated time of the conception, she was breastfeeding an average of 10 times in 24 hours. She was not, however, still amenorrheic and, hence, no longer using LAM LAM.. She had had two bleeding episodes and an "inadequate" ovulation before the cycle in which she conceived. The day of peak estrogen excretion (the estimated day of conception) was postpartum day 182. She had had intercourse 5 days previously, during a time when she did not report fertile-type mucus (it was described as sticky and shiny), and the woman did not believe herself to be fertile. Fertile-type mucus appeared 2 days after the day of sexual relations and lasted for 2 days.

The woman considered herself fertile for 3 days (the 2 days of fertile mucus plus 1 day). The conception probably occurred the day after that. Correct use of STM recommended abstinence from day 169 through day 184. Although her symptoms were not necessarily "fertile," they were different from-and elevated above-her basic infertile pattern. This was particularly significant because she had already experienced two bleeding episodes, which should have motivated her to attend to the rules for abstinence. abstinence . There are several points of note regarding this pregnancy and LAM. LAM . Since this woman had experienced two bleeding episodes before the conception, it did not occur during the period of LAM protection, since vaginal bleeding episodes are nearly always the consequence of some form of ovarian activity (e.g., ovulation, inadequate ovulation, estrogen withdrawal because of the collapsed follicle). The high level of natural pro-

Volume 165 Number 6, Part 2

NFP-LAM interface

2025

x

Sexual Relations Considered Herself Fertile Fertile Mucus Symptoms Abstinence Recommended

x

Estrogen Peak

169 170 171 172 173 174 175 176 177 176 178 179 160 180 161 181 182 162 163 183 164 184

Days Postpartum Fig. 4. Unintended pregnancy in mother No.2, Canadian center.

Good breastfeeding practices LAM

STM Good weaning practices

Birth

- - - - - - - - - - - - - - - -_. - -

-~

One Year

Fig. 5. Suggested emphasis in NFP-breastfeeding counseling. (Illustration provided by Georgetown University.) University.)

tection provided by LAM has ceased once lactational amenorrhea has ended. For NFP users who use LAM during the first 6 months, the occurrence of bleeding is a warning to be taken seriously. Perhaps if this woman had appreciated the significance of her bleeding episodes, she would have been more attentive to her symptoms and applied the rule more exactly.

Comment These data from the NFP and breastfeeding study suggest that the option to use LAM during the first 6 postpartum months may be helpful to some couples and appears to pose no additional risk of pregnancy in terms of the rates of adequate ovulation during the period of LAM protection. NFP programs would need to incorporate the teaching of good breastfeeding skills and principles to make this effort successful. This analysis implies at least three potential programmatic recommendations. These recommendations

are speculative but would appear to be logical corollaries of the findings reported here in the context of modern NFP programs. The first is that the use of LAM among NFP users should be encouraged when possible. There is a risk of pregnancy, but it appears to be no greater than the risk associated with using other NFP methods. To their benefit, couples could avoid unnecessary abstinence but, perhaps more important, could be relieved of the possible frustrations associated with trying to identify a dynamic basic infertile pattern. Second, couples should be urged to pay very serious attention to the return of menses or bleeding. Because the STM rules require couples to abstain until the observed postovulatory phase in the first three cycles, there can be a considerable time of abstinence, but it may be preceded by an abstinence-free phase if LAM is used. Third, in postpartum NFP programs good breastfeeding skills or principles should be taught. By helping

2026 Kennedy et al.

women to be successful breastfeeders, NFP programs may also observe parents who are more confident regarding both the care and nourishment of their child and their protection from pregnancy, longer natural durations oflactational infertility, fewer frustrations for couples and teachers, and greater professional fulfillment for teachers. All involved may also be pleased to know that they are reducing their child's risk of many infections and some chronic diseases. These are some potential benefits that NFP programs may consider potential. measuring and cultivating as they develop programs and strategies for testing the integration of LAM and NFP. Our support of breastfeeding families might take a profile suggested in the continuum in Fig. 5. At first, greater educational effort could be focused on breastfeeding skills (such as how to help a baby attach to the breast) and on breastfeeding principles (such as feeding the baby frequently day and night, avoiding bottles and pacifiers, and the the like). Also, of course, an overview of how to use NFP in the postpartum period could be given so that LAM rules can be followed as soon as LAM protection expires. Gradually the couple will need to know about good weaning practices and given detailed information about how to handle at least the first three menstrual cycles. NFP instructors would need to acquire more skill and more knowledge, but these would be germane to teaching couples to be in charge of their own natural infertility and recovery of fertility, fertility, since infant feeding practices are directly related to postpartum fertility.

We gratefully acknowledge the help of the technical staff responsible· responsible for conducting the hormone analyses

December 1991 Gyneco1 Am J Obstet Gynecol

and the NFP teachers who conducted the field work, Smith, ] oanne Holmes, Gillian Barker, namely, Dr. Meg Smith,Joanne Denise La Flamme, Lise Trepanier, Gail Byrne, and Anne McCarthy. Finally, our deep gratitude goes to the mothers who persevered in providing daily diary sheets and urine samples over months and years. years. REFERENCES 1. I . Labbok M, et al., aI. , eds. eds. Guidelines for breastfeeding in family planning and child survival programs. Washington, DC: International Institute for Studies in Natural Family Planning, 1990. 2. 2. Kennedy KI, KI , Rivera R, McNeilly AS. Consensus statement on the use of breastfeeding as a family planning method. Contraception 1989;39:477-96. 3. Family Health International. Breastfeeding as a family planning method (consensus statement). Lancet 1988; 2:1204-5. 4. Brown J6, JB, Harrison R, Smith MA. A study of returning 4. fertility after childbirth and during lactation by measurement of urinary oestrogen and pregnanediol excretion and cervical mucus production. production. JJ Biosoc Sci Suppl 1985;9:5-23. 5. Flynn AM, Docker M, BrownJB, Kennedy Kl. Ultrasonic patterns of ovarian activity during breastfeeding. AM J OBSTET GYNECOL GVNECOL 1991;165:2027-31. 1991 ; 165:2027-31. 6. Brown JB, Maclead SC, MacNaughton C, Smith MA, 6. Smyth B. AA rapid method for estimating oestrogens in using a semiautomatic sem iautomatic extractor. J Endocrinol 1968;42:515. 7. Brown JB, Blackwell LF, Cox RI, Holmes J, Smith MA. Prog Biological Chern Res 1988;285:119-38. 1988;285:ll9-38. 8. Bongaarts J. The proximal determinants of natural marfertility. The Population Council, 1982; Center for ital fertility. Population Studies working paper no. 89. 9. Short RV. Reproduction in mammals, book 4. 2nd ed. 1984:29. 10. Shaaban MM, Sayed GH, Ghaneimah SA. The recovery of ovarian function during breastfeeding. J Steroid Bio1987;6:1043-52. chern 1987;6:1043-52.