The need to measure the amount of breast milk suckled by a baby is important to many lactating mothers. This information will help to evaluate the baby's nutritional status, the need for breastfeeding guidance, or the use of milk substitutes, and therefore is important to the pediatrician, as well. Although breastfeeding is very important for the baby's health, many mothers discontinue breastfeeding and start using formulas. The main reason for stopping breastfeeding is the mother's false impression and worry that insufficient milk is consumed by the baby.
A number of devices for measuring the amount of milk expressed during breastfeeding have been proposed. These devices generally tried to adopt methods of fluid flow measurement and typically include a flow or capacity measuring device. These measuring devices are mounted on the breast during breastfeeding and measure the amount of milk flowing therethrough. A few examples of such devices are shown in U.S. Pat. No. 5,827,191 to Rosenfeld and US Patent Application publication no. 2008/0039741 to Shemesh et al., US 2005/0177099 to Dahan. Other devices propose the use of flow gauges utilizing ultrasound measurements or piezoelectric devices. These proposals did not solve the problem for two reasons: first, because such flow gauges are of relatively low precision, particularly when attempting to measure relatively small and varying amounts of liquid. Second, the invasive nature of the flow measurement devices interferes with the intimate nature of the mother/baby feeding and bonding process.
Yet other proposals include weighing the mother and/or baby or measuring the fullness of the baby's stomach before and after nursing, for example, as shown in US Patent application 2008/0097169 to Long, et al., 2008/0077040 to Ales, et al. and 2008/0077042 to Feldkamp, et al. These proposals did not succeed either, because of the lack of precision (precision of milliliters is required) and because of the inconvenience involved.
Accordingly, there is a long felt need for an accurate method of measuring the quantity of breast milk suckled by a baby, and it would be very desirable if such a method were non-invasive and did not interfere with the nursing process.