Women in early pregnancy are concerned with altering their lifestyles. Patients often ask about caffeine intake, exercise, and use of artificial sweeteners. Consumption of less than 200 mg of caffeine (two cups) daily is a reasonable recommendation because evidence is scarce for increased miscarriage at that dose.
Caffeine consumption has also been implicated in adverse pregnancy outcomes, specifically preterm birth and intrauterine growth restriction (IUGR).
Recent large, prospective studies have refuted this idea and found no relationship between caffeine consumption and preterm birth.
Based on these data, moderate caffeine consumption appears to be safe in pregnancy. As a result, the American College of Obstetricians and Gynecologists recommends limited caffeine intake during pregnancy to less than 200 mg daily. No evidence was found of adverse effects of caffeine.
The Centers for Disease Control and Prevention recommends 30 minutes of daily moderate exercise for general health and well-being in non pregnant individuals. This recommendation has been extrapolated to pregnant women because regular exercise has been shown to reduce the incidence of gestational diabetes, particularly in obese women. Certain types of physical activity – contact sports and sport associated with a higher incidence of falls, pose risks to pregnant women.
Moderate physical activity also appears to have no deleterious effects on birth weight and length of gestation after the first trimester.
Artificial sweeteners (saccharin, aspartame, sucralose, and stevia) have become ubiquitous in the American diet. Aspartame entered the food market in the late 1970s, and multiple safety studies showed no adverse effects or increase in fetal anomalies in normal individuals.
a newer artificial sweetener, sucralose, a substituted disaccharide, also appears to be safe to consume during pregnancy based on a number of animal studies. Less known about the safety of steviol glycosides, products generated from the South American plant Stevia rebaudiana.