Does Breast Feeding Space Babies?

Author: Couple to Couple League


The world's oldest and still most widely practiced form of birth regulation is breastfeeding. That statement draws much skepticism among ordinary people in Western culture, but it is recognized as still true by professionals in the fields of international demography and infant nutrition because they know how breastfeeding affects both health and birth intervals in primitive cultures around the world.

A professor of pediatrics put it this way: "Demographic data recorded prior to the 20th century from birth records all over the world indicate that the average spacing of children was about two years when mother's milk supplied the major source of calories for infants during the first year to 1.5 years of life."[1]

This was confirmed by a conference on lactation infertility (Bellagio, Italy, 1988) which stated: "Demographic data indicate that in many developing countries, the protection from pregnancy provided by breastfeeding alone is greater than that given by all other reversible means of family planning combined . . . Postpartum women should be offered a choice of using breastfeeding as a means of family planning, either to help achieve optimal birth spacing of two years, or as a way of delaying the introduction of other contraceptives."[2]

Furthermore, it is now recognized that it is not just any kind of breastfeeding that spaces babies. That's why the Bellagio conference added, "The (the mothers) should be informed how to maximize the antifertility effects of breastfeeding to prevent pregnancy.[3] What that means is this: only "ecological" breastfeeding provides extended postpartum infertility. This is a form of baby care which is characterized by constant mother-baby togetherness and frequent nursing, both by day and by night. How you can do ecological breastfeeding and still be an active member of your society is described in Breastfeeding and Natural Child Spacing: How Natural Mothering Spaces Babies.[4]

A couple of examples help to make the point. In a study conducted in the West African country of Rwanda, a culture in which there were no contraceptives or taboos against intercourse after birth at the time, there were no differences in the birth intervals of bottle feeding mothers in the city compared to those in the rural areas. On the other hand, among breastfeeding mothers, there were significant differences. Among the city mothers who were already developing patterns of separation from their babies, 75% conceived between 6 and 15 months postpartum. However, in the rural areas, mothers had their babies with them all of the time, and 75% of the rural breastfeeding mothers conceived between 24 and 29 months postpartum.[5]

An even more dramatic example of the effects of very frequent suckling is provided by the Kung tribe. (The exclamation point represents a clicking sound.) Anthropologists watched these people with stopwatches and found that the babies and toddlers were nursing an average of two minutes every 15 minutes, and the mothers were conceiving at about 35 months.[6]

Such extended periods of breastfeeding infertility are rarely seen in Western culture. First of all, only a few Western mothers nurse that long although their number seems to be increasing. Secondly, there is some speculation that the richer diet of Western women may contribute to an earlier return of fertility. Nevertheless, the Couple to Couple League office has received letters from a few women who experienced the return of their first postpartum menstruation between 34 and 42 months. In two separate studies, the Couple to Couple League found that the more common range for the return of the first menstruation among American women doing ecological breastfeeding is 12 to 16 months postpartum with an average of about 14.5 months.[7][8] And, just as there are a few who have a more extended duration of amenorrhea, there are also a few who experience the return of menstrual periods only two to four months postpartum.

The key to breastfeeding infertility is frequent suckling,[9] and that is simply a part of natural mothering which entails mother-baby inseparability. When mother goes to church, so does baby. When mother goes shopping, attends a meeting, or visits a friend, so does baby. And when baby indicates a need to nurse, mother obliges. When mother goes to bed at night, baby is either in the same bed, or at least the child's bed is right next to the parents' bed so that baby can nurse off and on during the night without any fuss and bother.

Most babies who receive the benefits of "natural mothering" and ecological breastfeeding start to take other nourishment somewhere between five and nine months postpartum and gradually take more and more to satisfy their growing appetites. However, they continue to nurse frequently, and breastmilk remains the primary nutrient for some time.

In the first six months, you can't beat the effectiveness of ecological breastfeeding! During the first three months postpartum the ecological breastfeeding mother's chance of getting pregnant while in amenorrhea is almost nil. Experts agree that any bleeding up to the 56th day postpartum can be ignored.[10] The next three months postpartum provide a 99% infertility rate to the ecologically breastfeeding mother who remains in amenorrhea.[11] God's plan provides the most effective method of family planning for the mother who follows His plan for mother and baby.

Eventually fertility returns. Usually, but not always, it is preceded by a "warning menstrual period," and frequently the first menstrual cycle will be infertile (sometimes others as well).

While the chances of pregnancy are at the 1% level during the first six months postpartum prior to the first menstruation, after six months the chance of pregnancy increases. Three studies have indicated that the actual rate of pregnancy is about 6%, a rate that is very competitive with actual use rates for both natural and unnatural methods of birth control.

When a couple seeks to reduce the 6% chance of pregnancy to something closer to 1% (i.e., one per 100 women years of exposure), the woman makes the observations that are standard in the Sympto-Thermal Method of natural family planning. She takes her temperature upon waking in the morning and checks for the appearance of cervical mucus and the opening of the cervical os several times during the day while taking care of her usual bathroom routine.

When she enters a time of fertility or potential fertility, the cervix secretes a mucus discharge that most women can notice easily by an examination of the wiping tissue after urination. In addition, the cervical mucus discharge usually produces a sensation of lubrication or wetness at the outer lips of the vagina. It appears that the breastfeeding mother usually has a longer and more obvious mucus pattern prior to the first postpartum ovulation than she has during regular cycles, thus providing her with an ample indication of the return of fertility. Many women also observe some physical changes that occur in the cervical os (for example, it opens up during the fertile time).

After ovulation, the temperature goes up and stays up for 10 to 14 days before the next period, the mucus dries up or disappears, and the cervical os closes.

Some women will have an almost constant discharge of a less fertile mucus for months during breastfeeding, and this can be distinguished from the more fertile type preceding ovulation. However, this brochure is not the place to describe in detail how to observe the mucus or how to interpret it as a symptom of fertility or infertility, and the same holds true for the changes in the cervix and the basal temperature pattern. The Art of Natural Family Planning[12] contains that information and has a chapter devoted entirely to detecting the return of fertility after childbirth, especially when breastfeeding. Thousands of women today are enjoying the breastfeeding relationship and successfully relying upon these signs to detect the return of postpartum fertility.

The purpose of this information is to affirm three statements:

1. The proper kind of breastfeeding definitely postpones the return of fertility. This kind of nursing is called ecological breastfeeding or natural mothering.

2. Eventually fertility returns even while the mother is engaged in ecological breastfeeding.

3. The return of fertility can be detected through the natural signs of fertility with a very high degree of accuracy.

The advantages of this form of natural family planning are obvious. Freed from the Pill, a women doesn't have to worry about what it may be doing to her body or to her milk and to her baby, nor does she have to worry about its abortifacient potential once fertility returns. Freed from the IUD, the nursing mother doesn't have to be concerned about what it is doing to her uterus which contracts as her baby nurses, nor does she have to feel guilty about its almost universally abortifacient mechanism once fertility returns. And she is freed from the messiness or unesthetic qualities of the traditional female and male barrier methods of contraception.

Ecological breastfeeding is another term for natural mothering, and on a worldwide basis it is still the most widely practiced form of birth regulation. Practically the only form of birth regulation in primitive cultures, it deserves more recognition in Western culture. And, as the practice of natural mothering is encouraged by groups of breastfeeding mothers and by teachers of natural family planning, such recognition is growing amid sighs of relief and shouts of joy among nursing mothers.


1. Robert L. Jackson, M.D., "Ecological breastfeeding and child spacing," Clinical Pediatrics 27:8 (August 1988) 373-377.

2. Kathy I. Kennedy, Roberto Rivera, and Alan S. McNeilly, "Consensus statement on the use of breastfeeding as a family planning method," Contraception 39:5 (May 1989) 478, 485.

3. Kennedy, above, 485.

4. Sheila K. Kippley, Breastfeeding and Natural Child Spacing: How Natural Mothering Spaces Babies (Cincinnati: Couple to Couple League, 1989).

5. Monique Bonte and others, "Influence of the socio-economic level on the conception rate during lactation," International Journal of Fertility (1974), 97- 102.

6. Melvin Konnor and Carol Worthman, "Nursing frequency, gonadal function, and birth spacing among !Kung hunter-gatherers," Science 207 (February 15, 1980) 788-791.

7. Sheila K. and John F. Kippley, "The relation between breastfeeding and amenorrhea," JOGN Nursing 1:4 (November-December 1972) 15-21.

8. Sheila Kippley, "Breastfeeding survey results similar to 1971 study," The CCL News, 13:3, (November-December 1986) 10 and 13:4 (January-February 1987) 5.

9. H. William Taylor, Effect of nursing pattern on postpartum anovulatory interval, (doctoral dissertation) (Davis: University of California) 1989.

10. Kennedy, above, 481, 485.

11. Kennedy, above. The Bellagio conference report noted three recent studies which found in the first six months of "full breastfeeding" and before any periods these percentages of pregnancy: 2%, 0% and 0.2%, for an average of 0.73%.

12. John and Sheila Kippley, The Art of Natural Family Planning (Cincinnati: Couple to Couple League, 1984). ------------------------------------------------------------------------

For further information about natural family planning you may refer to other material in this Topic or contact:

The Couple to Couple League P.O. Box 111184 Cincinnati, OH 45211 (513) 661-7612

This information is from a brochure titled "Breastfeeding: Does It Really Space Babies?" The brochure, the books listed above and related material may be ordered from Couple to Couple League direct or through CRNET's Catholic MarketPlace.

c 1980, 1991 The Couple to Couple League International, Inc.