Even if you’ve never had diabetes before, pregnancy can bring the disease on. If you’re pregnant or trying to become pregnant, you may want to heed this warning: studies have found that gaining weight during pregnancy—particularly within the first trimester—can increase your risk of gestational diabetes by 50%.

This risk is particularly large for women who are nonwhite, age 35 or older, and already overweight. Most women who are diagnosed with gestational diabetes are at 28 weeks or further along in their pregnancies. Here are some more facts about gestational diabetes:

Gestational diabetes is simply the condition of having high blood sugar during pregnancy. It can often be prevented by monitoring your blood sugar with the help of your doctor.

Getting gestational diabetes during pregnancy does not automatically mean you were diabetic pre-pregnancy. It also does not mean that you will continue to be diabetic after giving birth.

Most women who come down with gestational diabetes do not experience symptoms—or, if they do, the symptoms are very mild and unnoticeable.

Some symptoms you could experience include weight loss (even if your appetite increases), fatigue, increased urination, vomiting, nausea, increased thirst, blurry vision, multiple infections—particularly those of the skin, vagina, and bladder. Since most of these symptoms are already often symptoms of a normal pregnancy, they can be disregarded easily; tell your doctor if you are experiencing any of these symptoms.

Other risk factors include giving birth to a large baby in a past pregnancy (nine pounds or larger), a family history of diabetes, African or Hispanic heritage, and previous miscarriages.

Gestational diabetes doesn’t only affect Mom; baby is also at risk. The condition often results in larger babies that may sustain injuries during birth or call for a cesarean section. He or she may also experience hypoglycemia after being born.

Though many women will not continue to have diabetes after delivery, some will develop it five to ten years following the baby’s birth. This is often due to obesity.

To determine if you are at risk and to discuss prevention methods, talk to your obstetrician. Also, remember that eating for two does not automatically mean eating double the calories—a normal pregnancy only requires an additional 300 calories per day. By eating a balanced diet, taking the prescribed vitamins recommended by your obstetrician, and maintaining a healthy lifestyle with approved moderate to light exercise, you can usually keep gestational diabetes at bay.