Parents-to-be everywhere may have another reason to jump for joy. A new, highly accurate blood test may be able to tell you the sex of your baby earlier in your pregnancy.

Most couples have to wait until the second trimester of pregnancy (4-6 months), but the simple test could cut that time in half—as early as seven weeks. The test is highly accurate, too. Of the 201 women who were tested between 2003 and 2009, researchers were able to obtain sufficient samples from 189 and produce 100 percent accurate results.

When a woman is pregnant, her body will circulate her blood with blood from the fetus. For this test, a sample of the mother’s blood is screened for genes unique to the Y-chromosome of males. If these genes were present, researchers predicted a boy.

Early testing can also help doctors detect conditions such as Down’s syndrome and Rhesus-D disease (RhD). This method of testing has several advantages over invasive methods, such as fetal blood sampling (FBS), that can cause amniotic fluid leaking or miscarriage.

RhD sometimes results from a blood incompatibility between, for example, an Rh-positive mother and an Rh-negative child. If the mother’s body detects this difference, it may send antibodies against the baby. If it goes untreated, it can lead to jaundice, anemia, brain damage or stillbirth.

 “Noninvasive prenatal diagnosis of fetal Rhesus D genotype is sensitive and accurate and has been widely validated in Europe,” authors noted. “The United States should begin to undertake clinical trials to bring this technology to patient care as soon as possible.”

This test is currently not available to the general public, but continued success could mean it’s on the horizon. Its adoption into general health practices could help cut the risk of fetal complications of RhD.

The study was published in Obstetrics&Gynecology.