Kirsten Fisch, MSN, RNC-MNN, IBCLC, LCCE Kirsten is a women's health nurse who specializes in high-risk pregnancy and postpartum care. She is certified in Maternal Newborn Nursing, a board-certified lactation consultant (IBCLC), and a Lamaze Certified Childbirth Educator. She works with women from conception through the postpartum period. Passionate about empowering women throughout their reproductive journeys, Kirsten combines evidence-based care with compassionate support to promote the health and well-being of mothers and babies.
The first days after birth are a whirlwind of love, exhaustion, and adjustment for both you and your baby. If you’re planning to breastfeed, you’re likely hoping for things to go smoothly from the start. However, sometimes a baby may require additional nourishment through formula supplementation. This doesn’t mean breastfeeding has failed—it means you’re making the best choice for your baby in the moment. Let’s talk about when formula supplementation may be indicated in the immediate postpartum period and how it can be used supportively alongside your feeding goals.

1. Signs of Low Blood Sugar (Hypoglycemia)
Some babies are at risk for low blood sugar right after birth, especially those born to mothers with gestational diabetes, large-for-gestational-age babies, or babies who are small or late preterm. If blood sugar levels drop below a safe threshold, quick feeding is necessary. If breastmilk isn’t available or sufficient at the time, formula can be used to stabilize blood sugar levels.
Signs include:
- Jitteriness or tremors
- Poor feeding
- Low temperature
- Lethargy
2. Excessive Weight Loss
It’s normal for newborns to lose up to 7-10% of their birth weight in the first few days. However, if weight loss exceeds this amount or is happening rapidly, a pediatrician may recommend supplementation.
Why it matters:
Excessive weight loss can indicate that a baby isn’t getting enough calories. Supplementation can provide the necessary calories to regain weight, while lactation support helps improve milk supply and feeding techniques.
3. Signs of Dehydration
Dehydration in a newborn is a red flag. It can happen if a baby isn’t feeding well and isn’t getting enough fluid from breast milk alone.
Watch for:
- Less than 3–4 wet diapers per day by day 3
- Dark or red-tinged urine
- Dry mouth or lips
- Lethargy
In these cases, formula can be used temporarily while assessing breastfeeding effectiveness and supporting maternal milk supply.
4. Insufficient Milk Supply or Delayed Lactogenesis II
Some mothers experience a delay in their milk “coming in” (usually expected between 2–5 days postpartum). This might be due to complications during labor, retained placenta, or maternal health conditions.
How formula helps:
Using small amounts of formula to ensure the baby is nourished while the milk supply is being established can prevent complications and reduce parental stress.
5. Poor Latch or Ineffective Suck
A baby with tongue tie, jaw misalignment, or prematurity might not have an effective suck, leading to inadequate milk intake. If hand expression or pumping is not producing enough colostrum to meet the baby’s needs, supplementation may be introduced until effective breastfeeding can be established.
6. Medical Conditions in Baby or Mother
Certain medical conditions may require supplementation:
- Infants with jaundice need hydration to flush out bilirubin
- NICU admissions or separation of mom and baby
- Mothers with delayed recovery or on medications not compatible with breastfeeding
Important Notes About Supplementation
- It doesn’t have to derail breastfeeding. Supplementation can be used strategically with the support of a lactation consultant.
- Small volumes are often sufficient. A newborn’s stomach holds just 5–15 mL per feeding in the first days.
- Paced bottle feeding can mimic the breastfeeding rhythm and reduce nipple confusion.
- Supplemental nursing systems (SNS) can deliver formula at the breast to maintain stimulation.
Choosing to supplement doesn’t mean giving up on breastfeeding—it means you’re paying attention to your baby’s cues and making thoughtful, responsive decisions. With the right support, many families go on to successfully breastfeed exclusively or in combination with formula. There is no one-size-fits-all plan, and your feeding journey is valid, no matter the path it takes.
Need Help?
If you’re unsure whether your baby needs supplementation, ask to speak with a lactation consultant or your baby’s pediatrician. Early support can make all the difference.

Kirsten Fisch, MSN, RNC-MNN, IBCLC, LCCE Kirsten is a women's health nurse who specializes in high-risk pregnancy and postpartum care. She is certified in Maternal Newborn Nursing, a board-certified lactation consultant (IBCLC), and a Lamaze Certified Childbirth Educator. She works with women from conception through the postpartum period. Passionate about empowering women throughout their reproductive journeys, Kirsten combines evidence-based care with compassionate support to promote the health and well-being of mothers and babies.