Breastfeeding as a Form of Birth Control

Mom Breastfeeding Baby
Lactational Amenorrhea Method (LAM) of Birth Control. Photo © Anja Roesnick -

So you’ve just had a baby and are getting breastfeeding figured out -- congratulations! Perhaps there are many sleepless nights, and you can’t even imagine what it would be like if you were to get pregnant again. Because you're breastfeeding, you may not want to take a hormonal birth control right now, as you want to make sure nothing negatively impacts your milk supply or your baby. You’ve heard conflicting information about your fertility while breastfeeding, but what are the facts? What is the truth?

Following pregnancy and childbirth, a non-lactating woman can return to having regular menses as early as three weeks postpartum. But women who breastfeed their babies typically find their menses delayed throughout the period of exclusive nursing. Some women find they don’t have a menstrual cycle for the duration of the breastfeeding relationship, even if it lasts years. Noticing this trend throughout a large variety of cultures, socioeconomic classes, and settings around the world, researchers began to study how breastfeeding impacted fertility. What they found is that breastfeeding tends to delay ovulation, a phenomenon known as the Lactational Amenorrhea Method (LAM). Studies have shown it's more than 98% effective as birth control when three key criteria are met. LAM is more effective than the progestin-only birth control pill and various barrier methods.

3 Components for LAM to Be Effective

  1. Has your menstrual cycle returned? Menses must NOT have returned following childbirth for LAM to be effective. Bleeding in the first weeks following birth, and spotting up to the first 56 days, is normal and should not be considered a return to your cycle. However, beyond the first 8 weeks, if a woman has bleeding for two or more days, or has any bleeding she thinks could be her menstrual cycle, she should consider menses to have returned.
  2. Are you exclusively breastfeeding on demand, both day and night? Since hormonal changes in a woman’s body help suppress menses while breastfeeding, it is important to breastfeed on demand, night and day, in order to rely on LAM as an effective method of contraception. Though an occasional taste of food or other liquid is permitted, it should never replace a breastfeed. Like supplementation, sleeping through the night can give a woman’s body a long interval without breastfeeding, which can signal the body to no longer suppress ovulation.
  3. Is your baby over six months old? LAM can be relied upon when your baby is younger than six months. However, around the middle of the first year of life, a baby typically begins to eat solid foods, which can decrease breastfeeding frequency or duration, making the chances of ovulation increase.​​

    When these three components are present — baby under six months old, exclusively breastfed on demand, and no return to menses — then LAM is over 98% effective as a birth control method. It is safe for both mom and baby, as there are no hormones involved, and it’s easy. But if at any point a woman begins to feel uncomfortable relying on this method, another form of contraception should be used if the couple is still trying to avoid pregnancy.

    Though LAM is typically associated with being limited to the first six months of a baby’s life, research has shown that if a mother continues to not have menses, solids are fed to a baby after breastfeeds (rather than before), and the mother doesn’t go longer than four hours during the day — and six hours at night — between breastfeeds, that very few women become pregnant.

    Breastfeeding also increases the likelihood that when a mother does have a menstrual cycle, the first one will not be preceded by ovulation. Since ovulation is necessary for pregnancy to occur, this bleeding without ovulation gives a woman a “warning” that her fertility is returning, and that she should consider other contraception rather than rely solely on breastfeeding through LAM. But the longer a woman’s menstrual cycle is delayed past the first six months following birth, the greater the likelihood that ovulation will occur before the first cycle. If menses have not returned by a year, for example, there is a much greater likelihood that a breastfeeding woman will ovulate before the first menstrual bleeding than if menstrual bleeding first occurs at six months postpartum.

    When used during the first six months, breastfeeding and the Lactational Amenorrhea Method can be a highly effective form of birth control that allows a couple time after birth to decide what form of contraception is right for them.

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    Article Sources
    • Coly, Shirley. LAM – The Lactational Amenorrhea Method. World Alliance for Breastfeeding Action
    • Kennedy, K. I. (2002). Efficacy and effectiveness of LAM. In M. K. Davis, C. Isaacs, L.A. Hanson & A.L. Wright (Eds.), Advances in experimental medicine and biology; integrating population outcomes, biological mechanisms and research methods in the study of human milk and lactation (2002/05/25 ed., pp.207-216). New York: Kluwer Academic/Plenum Publishers.
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    • Nichols-Johnson, Victoria. The Breastfeeding Dyad and Contraception. Breastfeeding Abstracts November 2001, Volume 21, Number 2, pp. 11-12.