The Ramzi Theory: how accurately does it predict a baby's gender?

This could be your routine 12-week pregnancy dating scan or even a scan from as early as 6 weeks, if you need one or decide to book one privately.

But what exactly are you looking for? How can you tell where the placenta is? What are the boy or girl signs, according to Ramzi Theory? And is there any scientific evidence that Ramzi Theory can be accurate?

What is Ramzi theory? How does it work?

"The Ramzi Theory is apparently based on a relationship between your baby's sex and whether your placenta is on the left or the right of your womb," says Christoph Lees, Professor of Obstetrics at Imperial College London and a faculty speaker for the International Society of Ultrasound in Obstetrics and Gynaecology.

If your placenta is on the right, goes the theory, you're having a boy; if your placenta's the left, you're having a girl.

The theory was developed by Dr Saam Ramzi Ismail – hence its name – who published in paper in 2011 suggesting that his study of the location of the villous trophoblast cells that form the beginnings of the placenta in pregnancy ultrasounds conducted as early as 6 weeks could predict a baby's sex with an accuracy of 97.2% in the case of boys and 97.5% in the case of girls.

How do you spot the placenta on an ultrasound pic? How do you know if it's on the right or the left?

Well, this is the tricky bit.

Your placenta – or the area that is developing into the placenta (the villous trophoblast cells Dr Ramzi mentions) – will be in the white area immediately surrounding the black central area when your baby is developing. It tends to be a bit of a brighter white than the other white areas.

But, truth be told, it's really not that obvious to an untrained eyes. To be really sure, you need to ask your sonographer to show you where your placenta is while they are doing your scan.

And then there's an added complication: most ultrasound scan pics – if they are abdominal scans (where the sonographer moves a hand-held transducer over your belly) – are mirror images. In other words, what looks to be the right side on your scan pic could actually be the left side in real life.

Again, you'll need to ask your sonographer to confirm this, as sometimes the scan image you're given will not be a mirror image one – either because the actual scan was 'true to maternal side' or because the image has been flipped before it's printed out for you.

If you're having a transvaginal scan (common in scans before 12 weeks) it won't be a mirror image.

Ramzi Theory: examples for boy and for a girl

Ramzi Theory: pregnancy ultrasound scans showing boy examples and girl examples

The four scan pictures shown above (one shared by a member of our MadeForMums Community and the others shared by @the-nub-techs on Instagram*) all show the position of the placenta shaded or outlined in pink for a girl and blue for a boy.

You'll see that the 'boy' scans seem to show the placenta on the left but that's because they're mirror-image pictures, and the placenta is actually on the 'maternal right'. The same goes for the 'girl' scans: it looks like the placenta is on the right but it's actually on the 'maternal left'.

How accurate is Ramzi Theory?

It's about as accurate as flipping a coin.

And that's because, says Professor Lees, "there is no scientific evidence¹ behind this theory and, given that many placentas are neither on the left nor the right side, it is highly improbable that this has any validity at all."

Indeed, Dr Ramzi's published study – which was never peer-reviewed – has been replaced online by a page admitting that "unfortunately, Ramzi's method has not been confirmed in any other studies.... As a result, many [obstetricians] dismiss the validity to Ramzi's theory entirely."

About our expert Professor Christoph Lees

Professor Christoph Lees is Head of Fetal Medicine at Imperial College Healthcare NHS Trust. He qualified from Guy's Hospital, London, in 1990, with a sub-specialty accreditation in fetal-maternal medicine under Prof Kypros Nicolaides at the Harris Birthright Centre for Fetal Medicine, King's College Hospital, London. He established the fetal medicine unit at Addenbrooke's Hospital, Cambridge and was Head of Fetal Medicine at Queen Charlotte's and Chelsea Hospital. He is an international authority on fetal assessment and the use of Doppler ultrasound to assess the health of the baby. He leads research into high-intensity focused ultrasound and is a committee member of the International Society of Ultrasound in Obstetrics and Gynaecology.

About our ultrasound scan expert Gill Harrison

Gill Harrison is a highly experienced sonographer and radiographer, currently working as the Professional Officer (Ultrasound) at the Society and College of Radiographers. She was previously an Associate Professor at City, University of London and responsible for leading the medical ultrasound programme. She is a lead accreditor and external examiner, assessing the competency of ultrasound students and qualified sonographers in UK universities and hospitals. She is Chair of the Health Education England's Sonographer Training Group and was previously Chair of the European Federation of Radiographer Societies' Working Group for Ultrasound Surveys (2019 to 2022) and Chair of the Society and College of Radiographers' Ultrasound Advisory Group.

* The NubTechs offer an online gender prediction service, using both Ramzi theory and nub theory.

References:

^{1. 'The role of placental location assessment in the prediction of fetal gender.' The et al. Ultrasound in Obstetrics and Gynaecology. Dec 2010. doi.org/10.1002/uog.8569}
^{2. The Relationship Between Placental Location and Fetal Gender (Ramzi’s Method). Contemporary OB/GYN. Editor's note, October 2020.}

Pics: MadeForMums Community/The Nub Techs.

Helen BrownHead of Content Delivery

Helen is author of the classic advice book Parenting for Dummies and a mum of 3. Before joining MadeForMums, she was Head of Community at Mumsnet and also the Consumer Editor of Mother & Baby.