When should I do a fetal gender/sex test?

by | April 2022

There’s a lot to navigate during the first trimester of your pregnancy. In between dealing with morning sickness (that’s sometimes more like all-day sickness) and worrying about your baby’s health, you also have to make some pretty big decisions about prenatal genetic testing.

Here, we break down one of your options, early gender blood tests.

Why do we use the term gender test?

Most of us probably grew up thinking about sex and gender as the same thing — the label of male or female that you’re given at birth. Now, with the increased visibility of those on the transgender, nonbinary, and gender non-conforming spectrum, many are starting to understand that the idea of gender isn’t as simple as counting a person’s X and Y chromosomes.

When we talk about sex, we’re referring to the genetic sex that someone is assigned at birth, determined by their chromosomes and anatomy. Gender is a little more complicated. It refers to socially constructed characteristics, and it’s based on how a person perceives themselves.

Although our conversations about gender and sex are changing, many expecting parents still use the word “gender” when talking about finding out the genetic sex of their baby. That’s why JunoDx uses that term. However, we should note that a baby’s sex may differ from the gender they identify as later in life. 

What is a fetal gender test? 

A fetal gender test is a blood test that tells you the genetic sex of your baby. It can be performed as a solo test or as part of a noninvasive prenatal screening (NIPS) panel. Either way, the test works by analyzing tiny bits of fetal DNA found in an expectant mother’s bloodstream. 

Many new moms think of NIPS as the “early sex test,” but it can also tell you if there’s an increased risk for chromosomal abnormalities, such as Down syndrome, Edwards syndrome, Patau syndrome. 

Why should I do a gender blood test? 

Gender reveal parties aside, one reason expecting parents may ask for a fetal sex test is to avoid unnecessary invasive testing. Most sex-linked recessive disorders, such as hemophilia or Duchenne muscular dystrophy, are linked to the X chromosome. Since males only have one X chromosome, they’re typically the only ones affected by these diseases. 

*Females can get X-linked recessive disorders, but it’s very rare because it would require both the father and the mother to have or carry the disease.

If you know that one of your baby’s genetic parents is a carrier of an X-linked recessive disorder, your healthcare provider may recommend chorionic villus sampling or amniocentesis to determine if the baby is affected. Early gender testing can rule out the need for invasive testing if the baby is a girl.

When should I get a blood test to find out the sex of my baby? 

A gender blood test can help identify pregnancies with an increased risk of sex-linked recessive diseases. NIPS can go even further, identifying pregnancies that are for other chromosomal abnormalities. After you get your results, your doctor or genetic counselor will help you decide if you need any additional testing.

Full NIPS tests are usually done around 10 weeks gestation, but expecting parents can learn the sex of their baby as early as 7 weeks gestation with the Juno Early Gender Test. The process is affordable, accurate, and convenient. Simply use the testing kit in the comfort of your own home, send in your sample, and receive reliable results in just a few days.