A recent study found that a high intake of sweetened beverages - whether sugar-sweetened or artificially-sweetened - is associated with an increased risk of preterm delivery.
Premature newborns face an increased risk of complications such as immature lungs, pneumonia or intraventricular hemorrhage.
Aside from the risks surrounding preterm delivery, sweetened beverages also increase a baby's (and its mother's!) odds of developing more fat cells or becoming obese or diabetic later in life. They can also increase the risk of developing gestational diabetes or preeclampsia.
So what to drink? Filtered water is always a great option, as are herbal teas. If you must have something sweet, try no more than 4 oz. of a freshly-squeezed fruit juice, and consider diluting it with a bit of water to minimize blood sugar spikes.