Maintaining Milk Production once Back at Work
With the help of baby, a mother should take full advantage of her maternity leave to establish a good supply of milk before going back to work. It is suggested that establishing lactation before returning to employment is a key to enabling breastfeeding to continue as long as the mother wishes.
After returning to work, to meet her breastfeeding goals, a mother needs to maintain her milk production. Maintaining milk production is not always easy for employed mothers, especially when they do not know the basic dynamics affecting how much milk they make.
The following basic dynamics determines the (magic) number of times each day an individual mother needs to remove milk from her breasts to maintain her milk production:
the degree of breast fullness and
breast storage capacity.
Degree of Breast Fullness
Mothers are sometimes told to wait until their breasts feel full before expressing or breastfeeding. This advice reflects a basic misunderstanding of how milk production works. Research has found that the fuller breasts become, the slower milk was produced. More milk out = more milk in. Breasts are factories, not containers.
Milk contains a small whey protein called Feedback Inhibitor of Lactation (FIL). The role of FIL appears to be to slow milk synthesis when the breast is full. Thus milk production slows when milk accumulates in the breast (and more FIL is present), and speeds up when the breast is emptier (and less FIL is present). In one study showed after 6 hours without milk removal, one mother’s rate of milk production per breast was 22 ml per hour, by breastfeeding from that breast every 90 minutes and removing milk from her breasts more completely, her rate of production per breast increased quickly within the same day to 56 ml per hour. Thus more milk out = more milk in.
Breast Storage Capacity
A mother’s breast storage capacity refers to the maximum volume of milk available to her baby when her breasts are at their fullest. Unrelated to breast size, breast storage capacity is determined by the amount of room in her milk-making glandular tissue. Breast size is determined primarily by the amount of fatty tissue. The maximum volume of milk in the breasts each day can vary greatly among mothers. Two studies found a breast storage capacity range among its mothers from 74 to 606 g or ml.
So, breast storage capacity affects how long it takes for a mother’s breasts to become full. For example, a woman with a small storage capacity may become so full with 75 ml of milk in her breasts that her rate of milk production slows. However, in a woman with a larger breast storage capacity, this same 75 ml would not cause milk production to slow. This larger-capacity mother could, therefore go for longer periods between feedings without her rate of milk production slowing.
Although breast storage capacity can affect feeding patterns, it does not affect a mother’s overall ability to produce ample milk for her baby. Depending on her breast storage capacity, a mother’s “Magic Number” (number of daily milk removals needed to keep milk production stable) may be as few as 3‒4 or as many as 10‒12. But, when a mother’s total number of milk removals (breastfeedings plus milk expressions) dips below her “Magic Number”, her rate of milk production slows.
To get an idea of one’s “Magic Number” (assuming a mother is exclusively breastfeeding a thriving baby), count how many times every 24 hours baby breastfeeds. If the answer is 8 (which seems to be average), one can assume that to keep the milk production steady long term one will need to continue removing milk from the breasts at least 8 times each day. If a mother is expressing milk 3 times during a workday, this means she would need to breastfeed 5 times when together with baby. A change in routine can bring down the “Magic Number”, slowing milk production.
When a mother notices a drop in supply pumped, things she can consider are:
Has she reduced the number of pumping or breastfeeding sessions recently, or cut back on feeding/pumping in other ways?
How long does she breastfeed or express each breast at each session? Has this changed recently?
What is the longest stretch between breast drainings? A consistent stretch longer than 8 hours causes some mothers’ production to slow over time.
What brand/model does she use to pump with at work? Is it effective enough for her situation? Is the pump itself still effective or in need of replacement?
How much time does she spend skin-to-skin with baby each day? Time spent touching and holding enhances milk-making ;-)
Has baby started solids recently?
Has she started hormonal birth control recently, particularly those containing oestrogen?
Is she expecting either ovulation or her period soon, or has it recently started?
Is she perhaps pregnant?
Has she started a strict diet? Is she getting enough calories? Is she drinking to thirst?
Is she getting enough rest? Has she been under an unusually large amount of stress?
Has she been sick? Some medications can also decrease milk supply.
Talk to a Lactation Consultant or La Leche League Leader for more tips to increase milk output.
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