The Ramzi theory is a strategy for using the location of the placenta during early pregnancy ultrasounds to predict the sex of a baby.
Some people claim on online message boards that the method is as much as 97% reliable. Proponents refer to a study that involved a large number of ultrasounds. However, that study has not undergone peer review, and Dr. Saam Ramzi Ismail, who put his name to the theory, did not publish his research in a peer reviewed journal.
No major medical organization recognizes the theory as valid, and a 2010 study in a peer reviewed journal disputes the notion that placental location correlates with sex.
Sex differentiation — the process by which embryos begin developing male or female structures — begins early in development, usually about
The theory began with an ultrasound study of 5,376 pregnant people who had ultrasounds at either 6 or 18–22 weeks of pregnancy. However, just 1,200 participants had both ultrasound scans.
Researchers were able to see the external genitalia in 99% of male fetuses and 98% of female fetuses during the second trimester ultrasound. They found that 97.2% of male fetuses had a placenta on the right side of the uterus during the early ultrasound at 6 weeks, while 97.5% of fetuses had a placenta on the left side of the uterus.
Drawing on this data, they concluded that a placenta on the right side usually indicates a male fetus, while a placenta on the left side is a sign that a fetus is female. This distinction is the basis of the Ramzi theory.
Ramzi’s data support the theory and look compelling. However, taken in context, the Ramzi method falls short.
Many message boards feature stories of people who used the Ramzi method to predict the sex of their baby correctly. Any sex prediction method has a 50% chance of being right, though, so anecdotal evidence is not reliable.
In addition, there are several problems. First, there is no reason to believe that sex alone would change the location of the placenta. Ramzi does not provide any basis for this apparent difference. There is no evidence that sex-related hormones might move the placenta or influence its development or location.
Ramzi’s credentials are also questionable. Ramzi is not a medical doctor, but a doctor of public health. He has a master’s degree in medical ultrasounds. These credentials may not be sufficient for him to perform the sort of medical research that he has popularized.
Even discounting these two issues, however, no reputable scientist has replicated Ramzi’s results. This fact calls into question whether the data are real, and whether Ramzi correctly interpreted them.
Ramzi did not publish his research in a peer reviewed scientific journal, so doctors and other scientists have not been able to dig into the data or identify problems with the methodology.
A 2010 study used methods similar to those in Ramzi’s study to track fetal sex in 277 pregnancies. The researchers did not find a relationship between placental location and fetal sex. Instead, they noted that the location of the placenta varied in babies of both sexes.
The study did, however, find a relationship between early assessment of the genitals in the first trimester and biological sex. Using ultrasound, clinicians guessed the sex of fetuses based on their early genital development. They correctly predicted the sex of 103 of 108 fetuses (95%). This result suggests that early viewing of the genitals offers more accurate results than the Ramzi method.
For people eager to learn the sex of their baby, there is a first trimester alternative. Noninvasive prenatal testing (NIPT) uses the pregnant person’s blood to make a reliable guess as to the sex of the baby. This procedure often takes place as early as 9 weeks into the pregnancy — only 3 weeks later than Ramzi’s method promises to provide results.
NIPT works by identifying DNA from the fetus in the pregnant person’s bloodstream. It is not 100% accurate, but nor is any other sex testing method.
For those who can wait a little longer to find out, a second trimester ultrasound offers more certainty. A
Pregnancy is a waiting game. Waiting to learn about the health of the baby, the baby’s sex, and much else about the pregnancy can cause immense anxiety. People have long turned to unreliable folk methods to try to determine the biological sex of fetuses. While the Ramzi method claims to rely on science, there is no evidence that it is reliable.
Individuals who wish to learn the sex of their baby early should ask their provider about NIPT. It may also be possible to schedule an early second trimester ultrasound to confirm the results.