Can the Ramzi Theory Really Predict a Baby's Sex?

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If you recently learned that you are pregnant, you may be looking for ways to determine your baby's sex. While some people might want to know this information so that they can plan ahead, decide on a name, or start to bond with their little one, there may be medical reasons motivating someone's desire to learn more—especially if genetic disorders that are sex-specific run in the family.

Blood tests and ultrasounds are concrete, scientific ways to learn the sex of your baby, but there are plenty of myths and old wives' tales that supposedly offer alternative routes. One such method is known as the Ramzi theory.

But is the Ramzi theory actually a way to determine your baby's sex as early as the first trimester? Below we help you make sense of this particular theory, including how reliable it, is and what experts have to say.

What Is the Ramzi Theory?

Developed by Saad Ramzi Ismail, the Ramzi theory suggests that the location of the placenta during a six-week ultrasound could determine a baby's biological sex. That said, there is no peer-reviewed research to support this theory.

"The Ramzi theory is a method that attempts to predict the gender of a baby by looking at where the placenta is located on an ultrasound," explains Alex Robles, MD an OB/GYN and fertility expert at Columbia University Fertility Center. "According to the theory, a placenta on the right side of the uterus indicates a male baby, while a placenta on the left indicates a female. Unfortunately, no scientific rationale or evidence supports the Ramzi theory."

According to Dr. Robles, the Ramzi theory originated in the early 2000s, when Ramzi claimed to have found the correlation after analyzing thousands of prenatal ultrasounds. According to his findings, the theory "predicts fetal gender" in 97% of the cases.

"However, he never published his data," Dr. Robles says, "and no other researchers have replicated his findings."

What Experts Think

Although the Ramzi theory sounds promising—and an interesting way to determine your baby's sex—experts warn that it is not a reliable way to predict this information.

"I have not found the Ramzi theory to be accurate," Dr. Robles says. "There is no scientific evidence to support the accuracy of this method, and we do not recommend it as a reliable predictor of fetal gender."

In fact, an older study from 2010 attempted to replicate Ramzi's research and track the fetal sex in 277 pregnancies. But they did not find a relationship between the placenta's location and the baby's sex and noted that the location of the placenta varied despite the sex of the baby.

The researchers did, however, find a relationship between early assessment of the baby's genitals and their biological sex. In fact, they were 95% accurate in predicting a baby's sex using an ultrasound to observe the baby's genitals during the first trimester.

"I do not know of any doctor that uses the Ramzi theory," says Pietro Bortoletto, MD, MSc, a reproductive endocrinologist and director of reproductive surgery at Boston IVF. "The embryo is going to stick where it has the best chance of surviving and it has nothing to do with chromosomal sex of the fetus."

Methods for Reliably Knowing Your Baby's Sex

If you want to know the chromosomal sex of your baby, there are a number of options available to you. While it is always best to talk with your OB/GYN or healthcare provider to determine which option is right for you, here are several methods available that can give you some insight into the sex of your baby.

PGT-A Testing

PGT-A, or preimplantation genetic testing for aneuploidies, is a genetic test that is performed on embryos created through in vitro fertilization (IVF) and is used to screen for chromosomal abnormalities. PGT-A, sometimes also called preimplantation genetic screening (PGS), is used to screen embryos for extra or missing chromosomes. During that testing, you also can determine your baby's sex, says Dr. Bortoletto.

"With this test, two to 10 cells are taken out of of embryo to see if it is chromosomally-normal," he says. "You also can find out the sex of the embryo. This test is only done pre-pregnancy and is 99% accurate."

Noninvasive Prenatal Testing

Noninvasive prenatal testing is a blood test that helps determine the risk that a baby will be born with certain genetic abnormalities. This testing analyzes small fragments of DNA that are circulating in a pregnant person's blood.

"During pregnancy, some of the fetus's DNA circulates in the [pregnant person's] bloodstream," says Dr. Bortoletto. "Screening this DNA allows us to know the chromosomal makeup of the fetus. We also can determine the chromosomal sex of the fetus that way as well."

While this DNA circulates throughout the pregnancy, testing can be done as early as nine weeks, says Dr. Robles.

"[It is] one of the most reliable ways of predicting the sex of the baby," he adds. "It is 95% accurate."


Generally, an ultrasound is done halfway through your pregnancy and is usually used to check for fetal anomalies. During that time, you may be able to find out the sex of your baby, assuming they are in a position where their genitals are not only in view but also have been formed, says Dr. Bortoletto.

The younger the fetus is, the harder it is to tell the sex. In fact, one study found that male fetuses under 13 weeks were correctly predicted only 69% of the time while female fetuses were accurately predicted 86% of the time.

"Also, in some conditions, the genitalia are ambiguous and do not correspond with the chromosomal sex of the fetus," Dr. Bortoletto adds.

A Word From Verywell

There are a lot of advantages to knowing the sex of your baby before they are born. Aside from planning the nursery and registering for shower gifts, knowing more about your baby's chromosomal makeup also can allow you to prepare for genetic issues if there are any.

If you are interested in finding out the sex of your baby, talk to your OB/GYN or healthcare provider to determine what method is right for you. But, in the meantime, be wary of trying to determine your baby's sex using myths like the Ramzi theory. While it can be fun to speculate, it is not likely to be accurate.

8 Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Sherri Gordon
Sherri Gordon, CLC is a published author, certified professional life coach, and bullying prevention expert.