Ramzi theory: does placenta position predict the sex?

Where Ramzi theory comes from

Ramzi theory, also called the Ramzi method, is named after Saad Ramzi Ismail. The rule: “If the placenta is developing on the left side, the sex is female. If it is developing on the right, the sex is male.” The claim is that this shows “as early as six weeks via ultrasound,” as the Contemporary OB/GYN website sums it up (Contemporary OB/GYN). Left and right mean the sides of the uterus, so the mother’s left and right.

A 2009 abstract, then a 2011 web article

The earliest trace we found is a short abstract, numbered 1356, in a 2009 supplement to the journal Ultrasound in Medicine & Biology. Titled “The Relationship Between Fetal Gender and Placental Location and Other Pathologies,” it lists Ismail’s affiliation as a health region in Alberta, Canada (Ismail, 2009). We could read its listing, but not its text.

The version later accounts cite is a 2011 research paper on a medical website. That site “can publish research that is not peer-reviewed by other scientists or medical experts,” Romper wrote, citing BabyCenter (Romper, 2018). A page with the paper’s title, dated June 14, 2011, now sits on the Contemporary OB/GYN website. It carries an editor’s update dated October 23, 2020, and shows none of the study’s methods or results; we couldn’t open an archived copy.

What the study claimed

• The figures. At 6 weeks, the study is said to have found 97.2% of boys with the placenta on the right side of the uterus, and 97.5% of girls on the left. That’s how a 2014 student abstract from Moldova and Medical News Today report it (Draganel and Ipati, 2014, Medical News Today, 2020).
• The size. Medical News Today puts it at 5,376 pregnancies, and says “just 1,200 participants had both ultrasound scans,” at 6 weeks and at 18 to 22.
• Peer review. The study “has not undergone peer review,” Medical News Today says. We found no full, peer-reviewed paper of it.

What later studies found

We found five studies since 2010 that compared placenta side with the baby’s sex. All are small, and two are short conference abstracts. In date order:

• Sydney, Australia, 2010: no link. At an ultrasound practice, the placenta’s position was recorded on routine belly scans of 277 women with single pregnancies, with each baby’s sex from birth records. The placenta sat in the middle for 78 (28%). Of 89 babies with a right-sided placenta, 45 (51%) were boys; of 110 with a left-sided one, 63 (57%) were girls, the same share as in the whole group (159 of 277). “There is no relationship between placental location and fetal gender,” the authors concluded. The abstract doesn’t give the weeks (The and Chan, 2010).
• Chișinău, Moldova, 2014: a link, in a student abstract. At a congress for medical students and young doctors, two authors reported on 41 women scanned internally at 6 weeks. The sex was read on belly scans at 18 to 20 weeks; the abstract says it “will be confirmed” after birth. Of the boys, 83.3% had a right-sided placenta, and of the girls, 91.3% a left-sided one. It doesn’t give the numbers of boys and girls (Draganel and Ipati, 2014).
• Rasht, Iran, 2019: a link of unknown size. A team at Guilan University of Medical Sciences recorded where the pregnancy sac sat on internal scans of 751 women at 7 to 8 weeks, and compared it with the sex after birth. Right or left was significantly linked with the sex (P < 0.0001); front or back wasn’t. The abstract doesn’t say which side went with which sex, how strong the link was, or how many were followed to birth (Mirbolouk and colleagues, 2019).
• Tonekabon, Iran, 2021: a weaker link. At a hospital’s obstetric clinics, 192 women had belly scans at 7 to 11 weeks, with the sex checked after birth. Of babies with a right-sided placenta, 72% were boys; with a left-sided one, 70% were girls. Overall, guessing by the placenta was right 71.3% of the time; the abstract doesn’t say how front or back placentas were counted (Ghasemi and Shafti, 2021).
• Mosul, Iraq, 2022: no link. Radiologists from a Mosul teaching hospital scanned 67 women over the belly in the first trimester, at a private clinic, and read the sex on a second-trimester scan. About half of the 40 boys had a right-sided placenta. Of 27 girls, 11 were right-sided and 16 left-sided (P = 0.456). The site “has an insignificant correlation” with sex, the team concluded (Qasim and Hamid, 2022).

None matched the 97% reported for the original. And a link across a group isn’t an accurate guess for one baby: even in Tonekabon, about 3 in 10 guesses were wrong.

What about a placenta at the front or back?

Researchers have also asked whether a front (anterior) or back (posterior) placenta goes with one sex. The studies we found disagree:

• Najran, Saudi Arabia, 2023: a link. At one hospital, 142 women were scanned in the second or third trimester, and a doctor checked each baby’s sex after birth. Of the 73 babies with a front placenta, 66 were girls, and of the 58 with a back one, 48 were boys. The authors note the work was “confined to a solitary hospital” (Khalid and colleagues, 2023).
• Diyarbakır, Turkey, 2022: no link. A Dicle University team reviewed 302 women’s third-trimester records and found the placenta’s position “did not affect” the baby’s sex (Gündüz and colleagues, 2022).
• Rasht, Iran, 2019: no link at 7 to 8 weeks, as above.

Can you see the placenta, or the sex, at 6 weeks?

At about 6 weeks, counted from the first day of your last period, the pregnancy is still tiny: How early can an ultrasound see a pregnancy? shows what appears when.

The placenta isn’t yet a separate thing on the screen. A 2019 paper from a university fertility division in Memphis says that, by conventional wisdom, its location “cannot be identified before 8 weeks’ gestation,” when it first looks bright on ultrasound. The team judged the future site earlier, on internal scans at 5 to 6 weeks, from where the embryo and yolk sac sat in the sac. For 141 placentas in 111 patients, that site was consistent with the mid-pregnancy one in every case: 79.5% on the same surface, 20.5% spread onto the next. The abstract doesn’t mention the baby’s sex (Detti and colleagues, 2019).

The sex can’t show yet, either. What a scan shows is the baby’s sex, read from the genitals, and Mayo Clinic says the outer genitals start developing by the end of week 11 (Mayo Clinic). At 6 weeks, there’s nothing there yet to see.

Why left and right can flip on scan pictures

Trying Ramzi on a printout, or a phone photo of the screen? The sides are the first problem. A scan picture is a slice through the body. Which way it faces depends on the kind of scan, the view, how the probe is held and the machine’s settings.

“There is no international consensus on the orientation of transvaginal ultrasound images,” a Copenhagen team wrote in 2018, before testing two ways of showing them: top-down and bottom-up (Taksøe-Vester and colleagues, 2018).

The picture can also flip. “The mark on the probe always relates to one side on the monitor,” ISUOG notes, so a probe held the other way round reverses the picture. Its course shows a probe turned 180 degrees by mistake: a baby whose back is to the mother’s right “seems to be lying with its back to the left side of the woman.” Machines have display settings, too: training from the maker Siemens Healthineers describes a “U/D Flip” (up-down) feature for internal scans on one of its systems (Siemens Healthineers).

On a medical scan, labels settle which side is which: in the U.S., the AIUM says stored images should include the “anatomic location and laterality, when appropriate,” and “Image orientation when appropriate” (AIUM). A phone photo of a screen, or a cropped print, may show none of that, so it can’t reliably tell you which is her left and which her right.

Where the placenta’s position does matter

Doctors and midwives do check where the placenta is, for medical reasons such as how close it lies to the cervix. In England, the NHS says, “The position of your placenta will be recorded at your 18- to 21-week ultrasound scan.” If it’s “significantly low,” you’re offered an extra scan, “usually at about 32 weeks,” and “For 9 in every 10 women, the placenta will have moved into the upper part of the womb by this point” (NHS).

In the U.S., the guideline for standard medical pregnancy scans says the placenta’s location and its “relationship to the internal cervical os,” the inner opening of the cervix, “should be documented” in the second and third trimesters (ACR–ACOG–AIUM–SMFM–SRU). Your doctor or midwife checks this at your medical scans. A keepsake scan doesn’t check the placenta.

The verdict, and what does work

Ramzi theory is fun to try, but it can’t reliably tell you the sex. Its figures reach us secondhand, from a study Medical News Today says wasn’t peer-reviewed. No study we found matched them, and a picture alone can’t reliably show the mother’s left or right.

What works is something that reads the sex directly. Cell-free DNA screening (NIPT) is a blood test your doctor or midwife orders to screen for chromosomal conditions; the sex is a side result some labs report. Cleveland Clinic says it “can be done as early as 10 weeks of pregnancy,” and calls the sex result “highly accurate, but not 100% accurate” (Cleveland Clinic). On a scan, the sex is read from the genitals, and calls get surer as the weeks pass (gender scan accuracy by week).

Nub theory explains how early scans read the genitals, and When can you find out your baby’s gender? sets out every option.

Skull theory and the Chinese gender chart have their own guides. For fun, our boy or girl quiz runs through seven other old wives’ tales, from cravings to carrying high or low.

Done guessing? Pop your due date into the planner: it shows which of our sessions are ready for you now and which open after that. Whatever you type stays on your device.

A clear view instead of a guess, in Glendale

In Glendale, Los Angeles County, our Gender Confirmation is a 2D scan: “the classic black-and-white picture.” We book from 13 weeks, and we’re surest from 15. If you can wait until 15, do: we’re more confident, and a second look is less likely.

Once we have a clear view it can be over in 2 minutes. If your baby is being shy, we take longer. When we can’t be sure, we say so, and you come back for a free re-check (our promise). No ultrasound can promise 100%. If what we see is different from what you’ve been told, we tell you what we see, and how sure we are. If a blood test and a scan disagree, tell your doctor or midwife: there are several possible explanations, a few of them medical, and only they can look into it.

It’s a keepsake, not a medical exam: it doesn’t check the placenta or your baby’s anatomy, and it doesn’t replace the anatomy scan or any appointment with your doctor or midwife. The FDA and the AIUM discourage scans done only for keepsakes (FDA, AIUM); Safety, in plain words has their statements, and Is an early ultrasound safe for the baby? sums up the evidence. Find out from 13 weeks, confirm what you’ve been told, or see prices.

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