Blood test early in pregnancy to detect baby’s gender

While carrying the child, a mother's blood has cell-free fetal DNA floating around in it, and it's possible to use this to test for the baby's sex. In a meta-analysis that covered more, the test was found to be 95% efficient in guessing the sex of the fetus — and it works from as early as seven weeks. As the fetus and the placenta develop, the amount of DNA present in the mother increases, boosting the accuracy of the test, which hits its peak at 20 weeks.

This method is apparently already widespread in Europe, but America hasn't adopted the practice yet — despite the fact that it could mean a faster, easier way to find out the sex of the baby Stephanie Devaney of the National Institutes of Health in Bethesda, Md. and colleagues reported in the August 10 issue of the Journal of the American Medical Association.

In order to look at overall performance of the blood tests, the researchers conducted a review and meta-analysis of 57 studies conducted between Jan. 1, 1997 and April 17, 2011, totaling 80 data sets on 3,524 male-bearing and 3,017 female-bearing pregnancies. Generally, they found high sensitivity and specificity for Y-chromosome detection in maternal blood (95 percent and 99 percent, respectively).

Devaney and colleagues noted that a disadvantage of fetal DNA blood testing is the need to validate female sex, because the test looks for male, or Y-chromosome, DNA. Also, the test is not currently available at the doctor's office, has not yet been approved by the Clinical Laboratory Improvement Amendments (CLIA), and is not currently reimbursed by insurers. They also noted that many of the included studies were small, so it would be “beneficial to help validate test performance under highly controlled testing conditions.”

This could also help test manufacturers to “ensure that their claims are accurate,” as some companies that directly market the tests to consumers claim their products have an accuracy of 95 percent to 99 percent as early as five to seven weeks' gestation.

The real question is whether there's enough of the fetal DNA in the mother's system to test for chromosomal abnormalities, which would allow for other kinds of genetic testing that are arguably more important to the future baby's health.

Dr. Ananya Mandal

Written by

Dr. Ananya Mandal

Dr. Ananya Mandal is a doctor by profession, lecturer by vocation and a medical writer by passion. She specialized in Clinical Pharmacology after her bachelor's (MBBS). For her, health communication is not just writing complicated reviews for professionals but making medical knowledge understandable and available to the general public as well.


Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Mandal, Ananya. (2020, April 03). Blood test early in pregnancy to detect baby’s gender. News-Medical. Retrieved on July 12, 2024 from

  • MLA

    Mandal, Ananya. "Blood test early in pregnancy to detect baby’s gender". News-Medical. 12 July 2024. <>.

  • Chicago

    Mandal, Ananya. "Blood test early in pregnancy to detect baby’s gender". News-Medical. (accessed July 12, 2024).

  • Harvard

    Mandal, Ananya. 2020. Blood test early in pregnancy to detect baby’s gender. News-Medical, viewed 12 July 2024,


The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of News Medical.
Post a new comment

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.

You might also like...
Cuteness factor: Can baby schema explain our evolutionary caregiving instincts?