Cross-Nursing and Milk Sharing

La Leche League (LLL) fully supports the use of human milk for babies. The first priority of LLL is to help parents meet their infant feeding goals. A second priority is helping lactating parents express and safely store their own milk for their babies. When their own parents' milk is unavailable, babies may need human milk donated by other lactating parents. It is essential that this donated milk be safe.

If you have ever cared for someone else’s hungry breastfed baby the thought that things would be easier if only you could nurse the baby has probably crossed your mind. If you are lactating at the time you may have seriously debated the ethics of latching the baby on to your breast. Complete/full time nursing of another's infant, often for pay, is called wet-nursing. Cross-nursing is the occasional nursing of an infant whose own parent continues to breastfeed them on a regular basis.

Most situations in which cross-nursing is practiced are private arrangements made between the parents involved. Day care and babysitting seem to be the most common situations in which it is used. Cross-nursing or wet-nursing has also been used when hospitalization of a lactating parent is necessary. This is especially true in an emergency when the parent is unable to nurse or the potential effects on the infant of the parent's prescribed medication dictate temporary weaning. As it is rarely talked about, there is no clear data about how many breastfeeding parents cross-nurse occasionally or regularly.

The parent who is cross-nursing may experience a reduced supply of milk for their own baby. Various factors including the ages of the two babies and the regularity of the cross nursing schedule would affect whether or not the cross-nursing parent's milk supply would build up to meet the needs of both babies.

Cross-nursing can also affect the baby psychologically. A difference in the let-down, either in the timing or in the forcefulness, may confuse or frustrate an infant. Parents have reported that babies four months or older often refuse to nurse from another lactating parent and will choose to wait until their own mother or parent returns. Babies of this age also often refuse to take a bottle as a substitute for breastfeeding.

As an international organization, LLLI is aware that many mothers and parents in many cultures have informally shared their breastmilk and wet-nursed among family members and trusted friends. LLLI also recognizes that in times of severe maternal illness or death and natural disasters, sharing milk has been lifesaving for infants. When a parent contacts a Leader seeking information about using donated human milk a Leader will suggest they dialogue with an appropriate, licensed health care provider and contact a licensed human milk bank or other regulated and medically supervised human milk collection centre. There are currently four human milk banks in Canada operating in Calgary, Montreal, Toronto, and Vancouver. These milk banks abide by strict operating procedures, which include donor screening, medical supervision, bacteriological testing, pasteurisation, storage, and distribution. Due to limited supply the donated human milk available from the milk banks in Canada is only available by prescription to babies who meet strict criteria.

Lactating parents who donate to milk banks are screened carefully using the following criteria:
• they should be healthy, well-nourished and taking no medication.
• they should be screened for tuberculosis, syphilis, hepatitis-associated antigen, cytomegalovirus, herpes virus, HIV and other infectious agents.
• they should not smoke, drink alcohol, or consume large amounts of caffeinated or artificially-sweetened beverages.
• their own infants should be healthy, gaining well and free of all infections.

La Leche League does not suggest or recommend informal milk-donation/sharing arrangements, including wet-nursing or cross-nursing. La Leche League’s role is to provide information about the risks and benefits if questions arise about informal milk sharing so that an informed decision can be made.

The benefits of donor human milk include, but are not limited to: optimal nutrition, easy digestibility, and immunologic protection.

Risks of unregulated donor human milk can include transmission of bacteria or viruses. These have been found in milk expressed by women who are showing no signs of illness. Prescription and non-prescription drugs and environmental contaminants can be present in breastmilk. There is potential for unhygienic handling and improper storage of unprocessed donated milk. In a study of donor breastmilk purchased from ads found on the internet, some samples were found to have been extended with cow’s milk to increase the volume.

Babies of different ages require a specific composition of milk. Milk from the baby's own parent will provide the exact make-up the infant needs; another mother/parent whose baby is not the same age may not provide the same components in the same ratios.

La Leche League Canada Leaders are happy to help parents in any situation work out their best options for providing human milk for their babies.

Leaders can share with mothers information about safe milk expression and storage. They can provide mothers and parents with questions they may wish to ask of someone with whom they are considering entering into a milk sharing relationship. Helpful information on safe milksharing can be found in the LLLC article Cross Nursing and Milk Sharing and at the following websites:
Human Milk Banking Association of North America
Northern Star Mothers Milk Bank - Calgary
BC Women's Provincial Milk Bank - Vancouver 
Rogers Hixon Ontario Human Milk Bank - Toronto
Héma-Québec Public Mothers’ Milk Bank - Montreal
Eats on Feets - chapters worldwide