Exclusive Breastfeeding as Natural Birth Control

Using breastfeeding as birth control can feel risky. Almost every mom has a friend who got pregnant while exclusively nursing, which makes it easy to be skeptical about breastfeeding’s contraceptive protection. But like an obstetrician once told me—only abstinence is 100% effective. The truth is, we also all know people who got pregnant on the pill, with an IUD, or while using barrier methods.

Instead of relying on stories, let’s look at the actual research on LAM—the Lactational Amenorrhea Method.

Lactational: Making breast milk

Amenorrhea: Not having a period

Method: A natural form of birth control

The rules of LAM say that breastfeeding can effectively prevent pregnancy if:

1. You do not have your period

2. Your baby is under 6 months old (or has not yet started solids)

3. You breastfeed at least every 4 hours during the day and at least every 6 hours at night. 

A 2013 Cochrane review—the highest level of medical evidence—found that when practiced correctly, LAM is 98% effective in preventing pregnancy. That’s equivalent to hormonal birth control (91-99% effective) and even IUDs (99% effective).

Comparing non-barrier contraceptive methods:

	LAM	“mini” pill	IUD
perfect use protection	98%	99%	99%
protection as low as	93%	91%	99%
pros	no need for additional protection, no synthetic hormones, no effect on milk supply	highly effective in perfect use	ease of use, no need to remember anything
cons	must be aware of body changes and breastfeeding practices	need to remember daily hormonal effects on body antibiotics will lower protection rate	systemic inflammation

Unlike the pill or an IUD, LAM requires you to stay aware of your body’s signals throughout the postpartum period. Just saying “I’m breastfeeding, so I can’t get pregnant” isn’t enough. You need to regularly check if you still meet the criteria for LAM to work.

After giving birth, the hormone prolactin drives milk production. Prolactin also suppresses ovulation—no egg, no pregnancy. The more you nurse, the higher your prolactin levels stay, and the more effectively ovulation is blocked.

This isn’t a coincidence. It’s HaShem’s way of making sure moms and babies have time to recover before the next pregnancy. Before formula existed, frequent nursing naturally spaced pregnancies, protecting baby’s survival and mother’s health and recovery. 

Women’s bodies need time between births in order for our uteruses to heal, our ligaments to repair, our mental health to stabilize, and our nutrient stores to replenish. We need child spacing for human health! 

TLDR: the more often you breastfeed, the more your hormones suppress ovulation and therefore make pregnancy impossible.

Many women feel pressure to choose a birth control at their 6-week postpartum check-up, usually before going to the mikvah. Even if you don’t plan to rely on LAM for the full six months, knowing that LAM is a reliable form of birth control while breastfeeding can alleviate that pressure, giving you confidence to take the time you need to decide what long-term birth control is right for you. 

Here are some ways to maximize LAM’s effectiveness. These are NOT required aspects, but they tend to increase overall prolactin levels and therefore increase the time that women spend without ovulating or seeing a period:

• Breastfeed frequently and on demand. Let your baby nurse whenever they want, without watching the clock or sticking to a strict schedule. More frequent nursing means more stimulation, which keeps prolactin levels high.

• Limit pacifiers and use bottles only when necessary. Pacifiers in particular can replace valuable “comfort nursing” sessions—those soft suckles that actually help maintain prolactin levels.

• Make sure your baby has an effective latch. Some babies feed passively, relying on milk let-down to do all the work instead of actively sucking. If your baby frequently latches and relatches or seems to fall off the breast often, it may be a sign they’re not transferring milk efficiently. A strong latch ensures they’re fully emptying the breast, which signals your body to keep making milk—and keeps prolactin levels up. A skilled lactation consultant can help you assess your baby’s latch and teach them how to breastfeed more effectively.

• After introducing solids, if you’d like to try maintaining LAM longer-term, make sure to nurse before your baby’s mealtimes and maintain the exact same frequency of breastfeeding as you did before introducing solid foods. 

We know LAM works because large-scale studies have confirmed that most breastfeeding women who follow its guidelines won’t ovulate until after six months postpartum. That said, every woman’s body is different, and some women may indeed ovulate earlier. That’s why it’s so valuable to recognize the signs of returning fertility in your own body. Cultivating this body awareness is a skill that serves you through all the years between puberty and menopause.

As you and your baby grow, things start to shift. Most exclusively breastfeeding moms who follow LAM perfectly will see their period return sometime between 9-18 months postpartum—right in line with the recommended two-year gap between pregnancies.

If any of these changes happen, it’s time to explore other birth control options:

• Your baby starts solids and is nursing less frequently than every 4 hours during the day.

• Your baby starts sleeping longer stretches (more than six hours at a time, naturally or due to sleep-training).

• You go back to work and experience longer gaps between breastfeeding or pumping.

• You notice signs of fertility—such as more cervical fluid or spotting/bleeding.

LAM still provides up to 94% protection from pregnancy even at one year postpartum for women who don’t have their period back and are continuing to breastfeed at least every 4 hours during the day and at least every 6 hours at night even after introducing solids.

We don’t yet have research on whether pumping suppresses ovulation as well as direct nursing. If you’re exclusively pumping or pumping often, consider learning Fertility Awareness Method (FAM) to track ovulation or using a backup method for peace of mind.

Breastfeeding is more than just feeding—it’s a responsive and reciprocal biological system that nurtures both mother and baby. LAM can be an effective, natural way to space pregnancies, but it requires awareness and regular reassessment. By staying in tune with your body and your baby, you can use trust LAM for easy and intervention-free family planning.

Adina Kopinsky, IBCLC, is an International Board-Certified Lactation Consultant with over a decade of experience supporting mothers and babies. She is the co-creator of Body-Led Breastfeeding, a methodology that sees infant body language patterns as the key to breastfeeding success. Adina specializes in helping babies with persistent oral function challenges and those who struggle with bottle feeding.

Adina is the creator of The Pocket Prenatal, an innovative hybrid prenatal breastfeeding course that blends recorded content with live, hands-on instruction—bridging the gap between theoretical knowledge and usable skills for the postpartum period.

She serves as an assistant editor at the Journal of Human Lactation, the leading peer-reviewed publication in breastfeeding research, where she co-hosts their monthly literature review podcast.

Learn more or reach out to Adina directly at www.growinghappybabies.com.

Sources:

• Berens P, Labbok M; Academy of Breastfeeding Medicine. ABM Clinical Protocol #13: Contraception During Breastfeeding, Revised 2015. Breastfeed Med. 2015 Jan-Feb;10(1):3-12.

• Van der Wijden C, Kleijnen J, Van den Berk T. Lactational amenorrhea for family planning. Cochrane Database Syst Rev 2003;(4):CD001329.

• Tiwari K, Khanam I, Savarna N. A study on effectiveness of lactational amenorrhea as a method of contraception. Int J Reprod Contracept Obstet Gynecol 2018;7:3946-50.

• Eticha TG, Girma S, Mamo G, Asefa F, Birhanu A, Taye B, Alemu A, Nigussie K, Gedefaw A, Genet T, Amenu D, Mekuria T, Tura AK. Effectiveness of Lactational Amenorrhea Method in Ethiopia: A Multi-Center Prospective Cohort Study. Open Access J Contracept. 2023 Sep 4;14:149-157. doi: 10.2147/OAJC.S425574. PMID: 37693930; PMCID: PMC10488729.