Research: Baby-gender blood test 95% accurate

CHICAGO - Boy or girl? A simple blood test for mothers-to-be can answer that question with surprising accuracy at about seven weeks, a research analysis published in today's Journal of the American Medical Association has found.

Though not widely offered by U.S. doctors, gender-detecting blood tests have been sold online to consumers for the past few years. Their promises of early and accurate results prompted genetics researchers to take a closer look.

They analyzed 57 published studies of gender-testing done in rigorous research or academic settings. The authors said the results suggest that blood tests like those studied could be a breakthrough for women who are at risk of having babies with certain diseases and who could avoid invasive procedures if they learned their fetus was a gender not affected by those illnesses. But the study raises concerns about couples using such tests for gender selection and abortion.

Couples who buy tests from marketers should be questioned about how they plan to use the results, the study authors said.

The analyzed test can detect fetal DNA in mothers' blood. It's about 95 percent accurate at identifying gender when women are at least seven weeks pregnant - more than one month before conventional methods. Accuracy of the testing increases as pregnancy advances, the researchers concluded.

Conventional procedures, typically done for medical reasons, can detect gender starting at about 10 weeks.