The most common method of determining the gender of a baby is using medical ultrasound. Also known as diagnostic sonography or ultrasonography, medical ultrasound is a diagnostic imaging technique or therapeutic application of ultrasound https://en.wikipedia.org/wiki/Medical_ultrasound. Ultrasound scans use sound waves to build a picture of the baby in the womb. The scans are painless, have no known side effects on mothers or babies, and can be carried out at any stage of pregnancyhttps://www.nhs.uk/pregnancy/your-pregnancy-care/ultrasound-scans/. A scan usually takes around 20 to 30 minutes. However, the sonographer may not be able to get good views if your baby is lying in an awkward position or moving around a lot. If it’s difficult to get a good image, the scan may take longer or have to be repeated at another time.
According to a studyhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC5024945/, which had the objective to determine the accuracy of sonographer predictions of fetal gender during routine ultrasounds, Sonographic gender determination provides high success rates in the first trimester.
This means that sex may be determined by ultrasound as early as 14 weeks. Results of this study confirmed 100% accuracy in predictions made after 14 weeks gestation. The overall success rate in the first trimester group (11–14 weeks) was 75%. When excluding those scans where a prediction could not be made, success rates increased to 91%. Results were less accurate for fetuses younger than 12 weeks, with an overall success rate of 54%. Male fetuses under 13 weeks were more likely to have gender incorrectly or unable to be assigned. After 13 weeks, success rates for correctly predicting males exceeded that of female fetuses. Statistical differences were noted in the success rates of individual sonographers. Sixty seven percent of women were in favour of knowing fetal gender from ultrasound. Publicly insured women were more likely to request gender disclosure than privately insured women.