A sudden, temporary drop in milk supply is a common occurrence for breastfeeding parents once their menstrual cycle returns. This change, which typically happens just before or during the first few days of the period, is a normal physiological response to shifting hormones. Understanding that this is a temporary event, not a permanent loss of production capacity, provides reassurance. Preparing for this predictable dip with proactive strategies focused on hormonal support and increased milk removal is the most effective way to maintain a steady supply.
The Hormonal Cause of Temporary Supply Dip
The temporary decrease in milk production is directly linked to the return of reproductive hormones. Prolactin, the hormone responsible for milk production, is temporarily inhibited by the rise of estrogen and progesterone. As the body enters the luteal phase just before menstruation, these hormones climb. Elevated estrogen and progesterone suppress prolactin’s action, muting the “make milk” signal sent to the breast tissue and causing a noticeable reduction in volume.
Another factor contributing to the change is a temporary dip in serum calcium levels that often occurs around ovulation and menstruation. Adequate calcium is important for the efficiency of the milk ejection reflex, or letdown. A slight decrease in calcium can slow down the letdown reflex, which may cause the baby to become fussy at the breast due to slower milk flow.
Adjusting Nursing and Pumping Frequency
When hormonal changes signal the body to reduce milk production, the most effective countermeasure is to increase the demand for milk removal. Increasing the frequency of breast emptying sends a powerful signal to the body to upregulate prolactin receptors. Parents who primarily nurse should focus on increasing the number of times the baby feeds in a 24-hour period.
This mimics cluster feeding, where the baby feeds in short, frequent bursts to stimulate supply. Encouraging the baby to nurse on demand, even if sessions are short, helps maintain stimulation. Ensuring the breast is thoroughly drained at each feeding is also important, as this removes the milk-inhibiting protein feedback inhibitor of lactation (FIL).
For parents who pump, incorporating a power pumping session can effectively simulate the high-demand signal. A standard power pumping protocol involves pumping for one hour daily, replacing one regular session during the dip. This hour is typically structured as:
- 20 minutes of pumping
- 10 minutes of rest
- 10 minutes of pumping
- 10 minutes of rest
- 10 minutes of pumping
This intermittent schedule is designed to trigger multiple letdowns.
Dietary and Mineral Support
Specific nutritional adjustments can help support lactation during the menstrual period. Focusing on mineral supplementation is a primary strategy due to the calcium fluctuation that impacts milk flow. A temporary supplement of calcium and magnesium is often recommended to counteract the premenstrual drop in serum calcium levels.
The recommended daily dosage for temporary use ranges from 500 to 1,500 milligrams of calcium, paired with 250 to 750 milligrams of magnesium. It is important to take these minerals together, as magnesium aids in calcium absorption. This supplementation is best started a few days before the anticipated dip, typically around ovulation, and continued through the first two or three days of the period. Beyond minerals, certain foods and herbs known as galactagogues can offer supportive measures, though they do not replace frequent milk removal. Common examples include oatmeal and herbal supplements like fenugreek and blessed thistle.
Recognizing When to Consult a Specialist
While a temporary supply dip around menstruation is common, a persistent or severe decrease warrants consultation with a healthcare professional or a Certified Lactation Consultant (IBCLC). If the milk supply does not rebound within five to seven days after the period has concluded, an underlying issue may be present. A specialist can perform a clinical assessment, including a weighted feed, to accurately measure the infant’s milk intake. Other red flags include significant infant weight loss or persistent signs of inadequate milk transfer, such as a drop in wet or soiled diapers. A specialist can also help rule out secondary causes of low supply that may mimic or worsen a hormonal dip, such as anemia, thyroid dysfunction, or retained placental fragments.