Can you get pregnant while breastfeeding?

Breastfeeding is considered a natural but temporary form of birth control. It is called the lactation amenorrhea method (LAM) of birth control.

LAM is effective only if you breastfeed exclusively and frequently.  The time between two feedings must be less than 4 hours in the day or 6 hours at night.

When you breastfeed, your body produces increased levels of the hormone prolactin, which stimulates breast milk production. Elevated prolactin levels also reduce the release of hormones needed for ovulation—the process in which an egg is released from the ovaries. Since ovulation does not occur, pregnancy is less likely to happen.

This however is not full proof and pregnancy can occur even before the onset of your first period. Reducing the frequency of breastfeeding and supplementing with formula and solids can increase your chances of getting pregnant.

Is it safe?

Many woman may be concerned about continuing to breastfeed after finding out about being pregnant. One of the first questions that come to mind is will this affect the unborn child. Is my unborn child getting enough nutrients? Breastfeeding while pregnant is completely safe.

A study compared full-term delivery rates and newborn birth weights between pregnant women with more than one child who continued breastfeeding during pregnancy and those who did not. The findings showed no significant differences between the two groups in the rates of full-term versus preterm births, and birth weights were similar. The researchers concluded that breastfeeding during a normal pregnancy is safe and “does not increase the chance of adverse maternal or newborn outcomes.” They also emphasized that continuing to breastfeed during pregnancy is a personal decision for each mother.

It is important to note that the study excluded high-risk pregnancies. If you are expecting twins or other multiples, or if you have an increased risk of miscarriage or preterm birth, discuss the benefits and potential risks of breastfeeding during pregnancy with your healthcare provider.

Changes during pregnancy

Breastfeeding during pregnancy may be associated with the following changes and considerations:

Uterine contractions: Breastfeeding stimulates the release of the hormone oxytocin, which helps with milk let-down and can also cause mild uterine contractions. In most healthy, uncomplicated pregnancies, these contractions are not considered harmful. However, in women with a high-risk pregnancy—such as a history of recurrent miscarriage, preterm labor, or other obstetric complications—healthcare providers may recommend weaning or limiting breastfeeding based on individual circumstances.

Changes in breast milk: Breast milk continues to provide valuable nutrition during pregnancy, but hormonal changes can affect its composition, taste, and supply. Milk production often decreases as pregnancy progresses, and the milk may become saltier before transitioning to colostrum later in pregnancy. These changes may lead some older children to naturally reduce breastfeeding or self-wean.

Physical discomfort: Pregnancy can make breastfeeding more challenging. Common experiences include nipple tenderness, breast soreness, fatigue, and, during the first trimester, nausea or reduced appetite due to morning sickness. These symptoms may make continued breastfeeding less comfortable for some mothers.

Nutritional demands: Pregnancy and breastfeeding both increase the body’s energy and nutrient requirements. Mothers who continue breastfeeding during pregnancy should consume a well-balanced diet, stay well hydrated, and ensure adequate calorie intake to support their own health, the developing fetus, and the breastfeeding child.

Potential risks in high-risk pregnancies: Current evidence suggests that breastfeeding during a healthy, uncomplicated pregnancy is generally safe. However, in pregnancies with complications or risk factors, healthcare providers may advise caution. Concerns such as reduced fetal growth, low birth weight, preterm birth, miscarriage, or stillbirth are primarily related to the underlying high-risk pregnancy rather than breastfeeding itself. Women with a history of preterm birth, recurrent miscarriage, multiple pregnancy, or other pregnancy complications should discuss whether to continue breastfeeding with their healthcare provider.

Practical Considerations for Tandem Nursing

During the first few days after birth, Nancy Mohrbacher (2010) recommends giving the newborn priority at the breast to ensure they receive the colostrum, which is rich in nutrients and protective antibodies. This recommendation is especially important if the older child breastfeeds frequently, while it may be less of a concern if the older sibling nurses only occasionally. Tandem nursing can also help relieve breast engorgement and support the establishment and maintenance of an adequate milk supply.

Some mothers worry that their toddler might be consuming milk intended for their baby. However, the body is remarkably adaptable. Breasts typically adjust milk production to match the demands placed on them, so if they are nursing both a baby and a toddler, they can usually produce enough milk for both. In addition, toddlers generally breastfeed much less often than infants and obtain the majority of their nutrition from solid foods, making it unlikely that they will deprive the baby of the milk they need.