New Blood Test Can Identify Sex of Baby at 7 Weeks


Is it a boy or a girl? A new blood test can identify the sex of a baby as early as seven weeks into a pregnancy, but for now it is available in only a few clinics.

New test beats ultrasound test by about 3 months

The typical way to identify the sex of a baby is to have an ultrasound, which pregnant women can do at weeks 18 to 20, during the second trimester. According to the American Pregnancy Association, this is also the time period when ultrasound is used to diagnose fetal malformations, confirm multiples pregnancy, and verify dates and growth.

The new test, which was developed by Dr. Esther Guetta of the Sheba Medical Centre in Israel to be used as a research tool, involves testing a pregnant woman’s blood to look for traces of the infant’s DNA. Males have a “Y” chromosome and the male cells have an “XY” structure, while females have an “XX” formation. The test does not harm the infant and is reported to be 99 percent accurate.

While the new test may evoke words of praise and joy from some people, others are voicing concern because allowing couples to know the sex of their child so early in a pregnancy could encourage some to elect abortion if they don’t get the child they wanted. This possibility is especially keen in countries where baby girls can be considered less desirable, as in India and China.


In 2006, a blood test called the “Pink or Blue” by some people, was being sold with the promise that it could reveal a baby’s sex just six weeks into pregnancy. A British company, DNA Worldwide, began selling the test over the Internet in 2007, but did not ship to China or India.

The “Pink or Blue” also worked by analyzing the blood of the mother to look for fetal DNA. At the time, Dr. Patrick O’Brien, a consultant obstetrician and spokesperson for the Royal College of Obstetricians and Gynecologists told MSNBC that “At six weeks of pregnancy, it’s questionable whether the technology is that good.”

The Pink or Blue test was based on a method developed by scientists in Italy who reported their research in the journal Human Genetics in 2005. DNA Worldwide sold the test as “informational” rather than medical, so it was not regulated by health authorities.

The new test developed by Dr. Guetta, like the Pink or Blue, raises ethical questions and concerns, and she has called for committees of experts to meet to discuss them. Should a woman have the right to know her baby’s sex as early as seven weeks? Guetta told the Daily Mail, “If a woman wants and can afford the test, you could say it would be unethical to prevent her from getting it.”

American Pregnancy Association
MSNBC report, May 15, 2007
UK Telegraph