Can Pregnancy Cause Milk Supply to Drop?
Posted on April 13, 2026
Posted on April 13, 2026
Finding out you are pregnant while you are still breastfeeding can bring up a mix of emotions. You might feel excitement for your growing family. At the same time, you may feel worried about how this change will affect your current nursing relationship. One of the most common questions we hear is whether pregnancy itself can cause your milk supply to decrease.
At Milky Mama, we believe that education is the best tool for any breastfeeding parent. Understanding the biological changes in your body helps you make the best decisions for yourself and your children. If you want a deeper dive, our How to Support Your Milk Supply While Pregnant guide walks through this season in more detail. In this post, we will explore why milk supply often drops during pregnancy and how you can navigate this transition. We will also look at signs of a decrease and ways to support your body through this demanding time.
The short answer is yes: pregnancy often causes a significant drop in milk supply due to hormonal shifts that prioritize the new pregnancy.
When you become pregnant, your body undergoes a massive hormonal shift. These changes are necessary to support the developing fetus. However, these same hormones can interfere with the way your body produces milk for your older child.
During pregnancy, your levels of progesterone increase significantly. Progesterone is a hormone produced by the placenta that helps maintain the pregnancy. While it is essential for the baby in your womb, it is also a natural inhibitor of milk production.
High levels of progesterone suppress the action of prolactin. Prolactin is the hormone responsible for telling your breasts to make milk. This is why most people do not produce a full supply of milk until after the placenta is delivered. Once the placenta is gone, progesterone levels plummet, and prolactin can finally do its job. While you are pregnant, that high level of progesterone stays in your system, which often leads to a lower milk volume.
Around the midpoint of your pregnancy, usually between weeks 16 and 20, your body begins to transition. It moves away from producing mature milk and starts producing colostrum. Colostrum is the thick, yellowish, nutrient-dense "liquid gold" that is perfect for a newborn.
This shift is a biological priority. Your body is preparing to nourish the new baby. Colostrum is produced in much smaller quantities than mature milk. Because of this, even if you are nursing frequently, the total volume of liquid your older child receives will likely decrease.
Breastfeeding usually works on a supply and demand system. The more milk is removed, the more your body makes. However, during pregnancy, the hormonal influence is often stronger than the "demand" of your nursing child. You may find that even with frequent nursing or pumping, your output does not increase. This is one of the few times when the supply and demand rule does not work as expected.
Key Takeaway: The drop in milk supply during pregnancy is biological and hormonal. It is not a sign that your body is failing, but rather that it is prioritizing the new pregnancy.
The timing of a supply drop varies for everyone. Some parents notice a change almost immediately after conception. Others may not see a significant difference until they are well into their second trimester.
For many, the first sign of a supply drop happens early. During the first trimester, you might experience extreme fatigue and morning sickness. These physical stressors can take a toll on your body’s ability to maintain a high milk volume. Additionally, nipple tenderness is a very common early pregnancy symptom. This can make nursing uncomfortable, leading to shorter or less frequent feeding sessions.
Most breastfeeding parents notice the biggest drop during the second trimester. This is when the hormonal shift toward colostrum production is most intense. Studies suggest that up to 70% of breastfeeding parents experience a decrease in milk volume during this window.
It is important to remember that every body is different. Some people manage to maintain a partial supply throughout their entire pregnancy. Others find that their milk dries up completely by the fifth or sixth month. Your experience may also depend on how old your nursing child is and how often they are breastfeeding.
If you are concerned about your supply, there are several signs you can look for in both yourself and your nursing child.
Your child will likely be the first to notice a change. You may see the following behaviors:
You may notice changes in how your breasts feel and function.
If your nursing child is under one year old, it is vital to monitor their growth closely. Since milk is their primary source of nutrition, a drop in supply can affect their weight gain. If you notice fewer wet diapers or a plateau in weight, it is time to talk to your pediatrician.
Nursing during pregnancy is often called "nursing through." It can be a beautiful way to maintain a bond with your older child, but it also requires extra care for your own well-being.
Nipple tenderness is one of the biggest hurdles. To manage this, you can try:
Some pregnant parents experience "nursing aversion." This is a feeling of intense irritation, restlessness, or a "skin-crawling" sensation when the child latches. This is a common physical response to the hormonal changes of pregnancy.
If you feel this, know that you are not alone and you are not a bad parent. Many find that distraction helps. You can try listening to music, deep breathing, or reading a book while nursing. If the aversion is too strong, it is okay to set boundaries or shorten the feeds. A Certified Lactation Consultant Breastfeeding Help page can be a helpful next step.
If you plan to continue nursing after the new baby arrives, you are preparing for tandem nursing. This is the practice of breastfeeding two children of different ages. While it can be demanding, many families find it helps reduce sibling rivalry. During pregnancy, you can start talking to your older child about "sharing" the milk later on. If you want a structured overview of the transition, our Breastfeeding 101 class is a helpful next step.
What to do next:
- Monitor your child's wet diapers and weight.
- Communicate with your child if they are old enough to understand.
- Practice self-care to manage nipple sensitivity.
- Consult a lactation professional if you feel overwhelmed.
While you may not be able to fully override the hormonal drop in supply, you can certainly support your body. Maintaining your own health is the first step in ensuring you have enough energy for pregnancy and lactation.
Your body is working overtime. It is building a placenta, growing a baby, and trying to produce milk. This requires a lot of fluid. Dehydration is a common cause of a further dip in supply.
Aim to drink water throughout the day. If you find plain water boring, our Pumpin' Punch™ can be a great way to stay hydrated while enjoying a refreshing flavor.
You are essentially "eating for three" now. You need extra calories to support the pregnancy and your current milk production. Focus on nutrient-dense foods like:
At Milky Mama, we offer several treats that incorporate these ingredients. Our Emergency Brownies are a popular choice for parents looking for a delicious way to supplement their diet with oats, flaxseed, and brewer's yeast.
Many parents wonder if they can take herbal supplements to boost their supply while pregnant. It is important to be cautious. Some herbs that are safe during breastfeeding may not be recommended during pregnancy.
For example, we offer various herbal supplements like Lady Leche™. However, before starting any new herbal regimen while pregnant, you must consult with your healthcare provider or a certified lactation consultant. They can help you determine which ingredients are safe for your specific situation.
This product is not intended to diagnose, treat, cure, or prevent any disease. Consult with your healthcare provider for medical advice.
If your child is under the age of one, their primary nutrition must come from breast milk or formula. If your supply drops significantly during pregnancy, you may need to supplement.
At this age, milk is their only source of food. If your supply is no longer meeting their needs, you will need to supplement with donor milk or formula. Watch for signs of dehydration, such as a sunken soft spot or dark urine.
They may already be eating some solid foods, but milk should still be their main calorie source. You can try increasing the frequency of solid meals, but you may still need to offer a bottle to ensure they get enough nutrients.
For toddlers, a drop in milk supply is usually not a medical concern. They can get most of their nutrition from solid foods and other liquids like water or cow's milk (if they have no allergies). For this age group, nursing is often more about comfort and immune support than calories.
It is okay to feel sad if your supply drops. For many parents, breastfeeding is a core part of their relationship with their child. If your child begins to self-wean because of the change in milk, it can feel like a rejection.
Remember that your value as a parent is not tied to your milk volume. You are still providing love, security, and care. Whether you continue to nurse through the pregnancy or decide it is time to wean, you are doing a great job. Every drop counts, but your mental and physical health matters too.
There is a lot of misinformation about nursing during pregnancy. Let’s clear up a few common myths.
For most people with a healthy, low-risk pregnancy, breastfeeding is perfectly safe. The oxytocin released during nursing can cause mild uterine contractions, but these are generally not strong enough to cause preterm labor or miscarriage. Your body is designed to handle this. However, if you have a history of preterm labor or are carrying multiples, your doctor may advise you to wean.
The milk is never "bad." While the composition changes to colostrum, it is still incredibly healthy. It contains antibodies and essential nutrients. The only issue is the decrease in volume and the change in taste, which might not appeal to every child.
This is a very common misconception. While breastfeeding can delay the return of your period (a process called lactational amenorrhea), it is not a foolproof method of birth control. Many parents conceive while nursing before their first postpartum period even arrives.
If you want to keep nursing while pregnant, consistency and comfort are key.
Key Takeaway: You can support your body with hydration and nutrition, but you cannot always change the hormonal reality of pregnancy. Focus on what you can control.
Pregnancy can definitely cause your milk supply to drop, and for many parents, this happens as early as the first or second trimester. This change is driven by hormones like progesterone and the body's natural transition to colostrum. While it can be a challenging shift, many parents successfully nurse through their pregnancy or move into tandem nursing once the new baby arrives.
"Breastfeeding is a journey with many twists and turns. Adding a new pregnancy to that journey requires patience, grace, and extra support for your body."
You are doing an amazing job balancing the needs of your current child while growing a new life. Whether you continue nursing or choose to wean, we are here to support you. Explore our lactation snacks to help you stay nourished during this special time.
In a healthy pregnancy, your body is very efficient at prioritizing the developing fetus. As long as you are eating a balanced diet and taking your prenatal vitamins, your body will provide enough nutrients for both the baby in the womb and the child at the breast. It is the nursing parent who is most likely to become depleted, which is why extra nutrition is so important.
It is very difficult to significantly increase milk supply during pregnancy because the drop is caused by hormones rather than a lack of demand. While you can support your supply through hydration and nutrition, you may not be able to return to your pre-pregnancy volume until after the new baby is born and your hormones shift again. If you're looking for practical pumping strategies, our How to Increase My Milk Supply While Pumping: Expert Tips guide can also be useful.
Yes, it is very common for toddlers to self-wean during pregnancy. This usually happens because the milk volume has decreased or the taste has changed as the milk transitions to colostrum. If your toddler loses interest, try not to take it personally; it is a natural reaction to the physical changes in the milk.
Most people can safely breastfeed throughout their entire pregnancy. However, you should consult your healthcare provider if you experience vaginal bleeding, uterine pain, or have a history of preterm labor. Additionally, if nursing is causing you significant physical pain or mental distress, it may be the right time to consider weaning for your own well-being.