Milk Intake During Pregnancy Can Influence Infant Weight at Birth

A recent Danish study looked at the influence of milk intake and milk constituents on intrauterine growth. Results revealed that higher intake of milk during pregnancy is associated with greater infant weight and length at birth.

The composition of milk differs widely between different species, but overall, milk is an excellent source saturated fat, protein, lactose (a type of sugar), calcium and vitamin C. Cow milk is by far the most commonly consumed type of milk in the western world and it contains many potentially growth-promoting factors.

The study used data on midpregnancy diet from 50,117 women. All results were adjusted for various factors such as mother's parity*, age, height, body mass index (BMI) before pregnancy, gestational weight gain, smoking status, and total energy intake, as well as the father's height and the family's socioeconomic status.

*The number of times a woman or female animal has given birth.

Mean milk intake among women was 3.1 ± 2.0 glasses/day. Higher median milk intake was associated with increased risk of LGA (large for gestational age) and decreased risk of SGA (small for gestational age). Increased milk consumption during pregnancy also demonstrated a trend towards greater birth length and weight, slightly greater abdominal and head circumference and greater placental weight. Infants, whose mothers drank at least 6 glasses of milk per day, were found to be around 60 % more likely to be large and 50 % less likely to be small at birth. Prevention of small size for gestational age may be of benefit in prevention of type II diabetes and cardiovascular diseases later in life, whereas on the other hand, rapid early growth rate may carry increased risks for obesity, cancer of the breast and reduced longevity.

Interestingly, birth weight was associated with the intake of dairy protein, but not with the intake of dairy fat or protein from cheese or nondairy protein. "More research is needed to identify the causative factors in cow milk and to examine whether the possible growth-stimulating effect of cow milk is beneficial or deleterious to the health of the fetus in the short term as well," study authors say.

Source: Milk Intake in Pregnancy Linked to Larger Infant Size at Birth (Medscape) [1]