Blood test developed to determine fetal gender accurately as early as five weeks

Kathleen Blanchard's picture

Dutch researchers have developed a way for expectant parents to determine the gender of their baby as early as five weeks. A simple blood test can now predict fetal genderwith one hundred percent accuracy, and may lead to the development of home diagnostic tests.

The study that took place in the Netherlands included 201 expectant mothers, between 2003 and 2009. According to Dr. Peter Scheffer of Sanquin Research Amsterdam a scientist at the University of Amsterdam where the study was conducted, the value of the blood test lies in reducing anxiety for parents about hereditary diseases that could be treated in-utero.

"It eliminates the dangers associated with invasive testing," says Scheffer. "With regard to fetal sex determination, it would allow for definitive sex determination earlier in pregnancy, sparing most female fetuses from unnecessary invasive testing" when there is fear of X-linked disorders, "or guiding clinical management. It can also help reduce parental anxiety."

For instance, the non-invasive blood test would allow expectant parents to intervene early in cases where male birth is expected – conditions that can be passed genetically to males include hemophilia and Duchenne muscular dystrophy. For females, Congenital adrenal hyperplasia that could be passed onto children, in-utero treatment would be an option by knowing the gender of the fetus early.

The study authors write, “Noninvasive fetal sex determination is a clinical reality. There is no longer a need for invasive procedures to determine fetal sex. Fetal sex determination in maternal plasma allows for early knowledge of the fetal sex, adding to timely clinical management. It can reduce the need for invasive procedures in pregnant women carrying an X-linked chromosomal abnormality up to 50%, decreasing the risks for iatrogenic damage.”


According to an MSNBC report however, testing the gender of a fetus early could lead to abortions for reasons other than those conducted out of medical necessity. The non-invasive blood test could pose ethical problems. University of Pennsylvania bioethicist and contributor Arthur Caplan, Ph.D. says, "elective abortion is just about the only option in response to fetal testing."

The researchers for the current study were able to predict the fetal gender with accuracy by extracting DNA from maternal plasma, presumably by using because of the volume of DNA used for the testing. The authors write, “Other groups that used much smaller volumes of plasma and extracted DNA reported a higher frequency of repeat testing, reported more false-negative results, or were not able to issue results before the 10th week of gestation.”

The researchers say in cases where fetal gender cannot be determined using the non-invasive blood test, "eg, CAH or androgen insensitivity…ultrasonographically and invasive testing is to be offered…With our approach, there is no need for ultrasonography if the presence of fetal DNA is confirmed."

The retail market for early blood testing that can determine fetal gender as soon as five weeks is expected to boom. Current tests available for parents and sold on the internet to determine fetal gender have not proven reliable.

doi: 10.1097/AOG.0b013e3181c3c938