When a woman receives a positive pregnancy test, especially for their first child, the feeling of happiness and excitement is immeasurable. You look forward to the future of your healthy pregnancy -- and you absolutely should. But you should also know that once in a while a problem can develop that you should be aware of.

Molar pregnancy, or hydatidiform mole, is a benign tumor in the uterus.

It occurs when an egg is fertilized and instead of an infant developing, the placental tissue beings to grow out of control at a rapid rate, filling the cavity with cyst-like structures that look like grapes.

Symptoms of molar pregnancy include bleeding, vomiting, pelvic pressure, an enlarged uterus. Other side effects can involve side high blood pressure, anemia, or elevated thyroid function.

One major risk factor for women is a past history of molar pregnancy. The cause is genetics; due to an abnormal multiplication of the father's chromosomes at the time of fertilization.

The diagnosis is made by ultrasound, when no fetus is visible, but instead a very cystic placenta filling the uterus is identified.

A common blood test that is a red flag for this condition is one that measures levels of the hormone HCG. In cases of molar pregnancy, HCG levels are typically extremely elevated. The treatment is usually through a dilation and curettage, or D&C. In severe cases, the condition may require a hysterectomy.

After initial treatment, the next course of action is to monitor blood tests until HCG levels are negative. It is advised for patients not to get pregnant until blood levels are normal and the patient gets the go-ahead from their doctor.

However, in some cases, after the D&C pregnancy hormone levels persist, leading to a condition called persistent gestational trophoblastic disease, or GTD. If this occurs, your doctor may have to treat you with chemotherapy.

The key here it s to define what molar pregnancy is for all my readers to make sure you are an informed patient and have a medical team that is involved in monitoring your pregnancy. I realize this is a hard topic to learn about, but the silver lining is that successful treatment is available and can cure you.

Dr. Manny Alvarez serves as Fox News Channel's senior managing health editor. He also serves as chairman of the department of obstetrics/gynecology and reproductive science at Hackensack University Medical Center in New Jersey. Click here for more information on Dr. Manny's work with Hackensack University Medical Center. Visit AskDrManny.com for more.