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12 Reasons You’re Not Losing Weight After Pregnancy

Pregnancy is a beautiful yet physically demanding journey. You gain weight for nine months, then expect your body to quickly return to normal after delivery. While some women lose their post-pregnancy weight naturally, others struggle to do so. Since everyone’s bodies and habits differ, it may take several months or even years to shed the extra weight. This can be frustrating for many women. So, why are some people not losing weight after pregnancy while others drop it with no issue? Let’s explore some potential reasons you’re not losing weight after pregnancy and a few roadblocks every new mom experiences.


Common Causes of Postpartum Weight Gain

Postpartum weight gain is often attributed to various factors, from hormonal changes and new parent fatigue to sedentary habits and unhealthy eating. Although it can feel frustrating and lonely, it’s extremely common for women to gain weight after pregnancy. In fact, most women do—at least to some degree. Here are some of the most common causes of postpartum weight gain among new mothers.


1. Hormonal Changes

One of the most significant factors in postpartum weight gain is hormonal changes. During pregnancy, your body produces high levels of hormones like estrogen and progesterone, which help support the growth and development of your baby. After childbirth, these hormone levels drop rapidly, which can lead to changes in metabolism and weight gain. The hormone prolactin, which stimulates milk production, can also contribute to weight gain, increasing appetite and promoting fat storage.



Polycystic ovary syndrome (PCOS) is a hormonal condition affecting the ovaries' function. Women with PCOS tend to have significant hormonal imbalances, which can affect how the body stores and uses fat. This can lead to weight gain, particularly in the abdominal area.

Elevated levels of insulin and androgens are usually the main culprits in PCOS. These imbalances may cause metabolic changes, making it even more difficult for your body to burn fat and regulate blood sugar levels. Some women with PCOS may also experience increased appetite, which can make it more challenging to maintain a healthy diet and control weight. Additionally, PCOS may cause breastfeeding difficulty, which can contribute to postpartum weight gain.


3. Diabetes

In the U.S., about 1% to 2% of pregnant women have type 1 or type 2 diabetes, and about 6% to 9% develop gestational diabetes. Regardless of the type, diabetes can contribute to postpartum weight gain in several ways. Women with diabetes may experience insulin resistance, causing the body to produce more insulin, which can then lead to weight gain. Additionally, some medications used to treat diabetes can cause weight gain as a side effect. Moreover, women with diabetes may be advised to consume more calories during pregnancy to ensure adequate fetal growth, which can also contribute to weight gain.

After giving birth, women with diabetes may find it challenging to lose weight due to several factors. They may need to continue taking medications to manage their blood sugar levels, which can affect weight loss efforts. Some women with diabetes may also experience decreased insulin sensitivity after giving birth, making it more challenging to regulate blood sugar levels and manage weight.

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4. Postpartum Depression

Postpartum depression (PPD) is a type of mood disorder that can affect women after childbirth. It’s marked by extreme sadness, mood swings, anxiety, and more. PPD can lead to postpartum weight gain, as it may affect your motivation to engage in physical activity and adhere to a healthy diet. Women with depression may also engage in emotional eating, where they consume high-calorie foods to cope with negative emotions.

Lack of sleep, which is common in postpartum depression, can also contribute to weight gain by altering hormones that regulate appetite and metabolism. Some antidepressant medications used to treat postpartum depression can cause weight gain as a side effect.


5. Postpartum Thyroiditis

Postpartum thyroiditis is a condition in which the thyroid gland becomes inflamed after childbirth, causing it to malfunction. This can lead to a variety of symptoms, including weight gain. The thyroid gland produces hormones that regulate metabolism, so when it’s not functioning correctly, metabolism can slow down, leading to weight gain.

Women with postpartum thyroiditis may also experience fatigue, which can make it more challenging to engage in physical activity and maintain a healthy diet. As the thyroid gland heals and begins to function correctly, weight loss may occur.


6. Postpartum Healing

After childbirth, your body needs time to heal. This postpartum recovery period can lead to weight gain in a few ways. Firstly, the body goes through significant changes during pregnancy and childbirth, and it takes time to recover fully. The healing process can be slow, and the body may need time to rest before engaging in physical activity or attempting weight loss efforts. This could mean that the scale goes up a few pounds. However, it's critical to avoid putting too much strain on your body until your doctor has cleared you.


7. Breastfeeding

Breastfeeding is a natural way to provide nutrients to the baby and also helps in weight loss. While breastfeeding burns quite a few calories, some women may experience increased hunger and appetite, leading to overeating and weight gain. Some women may also be advised to consume more calories while breastfeeding to ensure adequate milk production, making losing weight more challenging. Additionally, your body may store extra fat for milk production. Even if you gain a few extra pounds breastfeeding, it’s still the best way to provide your baby with the nutrients they need for healthy development.


8. Sedentary Habits

Physical activity is essential for weight loss, regardless of if you’ve just had a baby. However, after childbirth, almost all new moms are busy focusing on being a parent, leaving little time for exercise. After your doctor has cleared you, consider adding some light physical activity such as walking, yoga, or postpartum exercises you can do at home to your schedule. Any type of regular exercise helps boost metabolism, burn calories, and improve overall health.


9. Poor or Unhealthy Diet

Eating a healthy and balanced diet is one of the best ways to help with post-pregnancy weight loss. Unfortunately, that’s easier said than done, especially if you’re breastfeeding and trying to support your milk production. Over time, consuming too many calories can lead to weight gain, but the nutritional value of each calorie also plays a huge role. A healthy diet that includes lean protein, fruits, vegetables, whole grains, and healthy fats is necessary for weight loss. Even if you need to eat more, try sticking to whole, nutritious foods and limiting processed or sugar-filled foods to help avoid weight gain.


10. Dehydration

Dehydration affects the body's metabolism and ability to burn calories, making it a common roadblock to postpartum weight loss. When you’re dehydrated, the body slows down its metabolic rate to conserve energy. A lower metabolic rate equals fewer calories burned at rest. Dehydration can also cause the body to retain water, leading to bloating. Finally, dehydration can affect physical activity levels by reducing endurance and causing fatigue, making it harder to engage in exercise and burn calories.


11. Lack of Sleep

Newborns require constant attention and care, which can lead to sleep deprivation for new mothers. Although you’re not likely to return to your usual pre-baby schedule right away, sleep deprivation can lead to weight gain as it affects hormones that regulate appetite and metabolism. Try to get as close to seven to eight hours per day, even if that means napping whenever possible.


12. Stress

Although it’s easier said than done, trying to de-stress and remain calm can help with your postpartum weight loss efforts. The hormones released during stress tend to increase appetite, leading to overeating. Stress can also affect sleep and motivation to exercise, making it difficult to lose weight. Try to find a stress management technique that works for you, such as yoga, meditation, or counseling.


Weight loss after pregnancy is a gradual process that requires patience and dedication. To help support a healthy breastfeeding journey, Byram Healthcare has plenty of resources, experts, and products available. We also have a large selection of insurance-covered breast pumps available to new and expecting mothers to help supplement their nursing sessions. This is a great way to share feedings with your partner or other caregivers, giving you time to rest and de-stress. To learn more, visit our breast pump product guide and start your order today.