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The sex of the baby depends on the mother's blood pressure readings on the eve of conception
Last reviewed: 02.07.2025
Many future mothers and fathers try to guess the sex of the future baby in advance, paying attention to all sorts of signs and beliefs.
We remember from school that the sex of a future person is determined by a pair of chromosomes that a woman receives with a sperm: X and Y. If the female chromosomes XX are connected to Y, then a boy is born, and if with X, then a girl is born. But: the probability that a child of a male or female gender will be born is determined as 50 to 50. How can you predict the sex of a child?
Recently, Canadian experts voiced the opinion that the mother's blood pressure readings before conception determine the sex of the baby.
Until now, science could not clearly substantiate the birth of boys or girls in a family. Theories were voiced about the peculiarities of parents' nutrition, lifestyle, etc. For example, it was assumed that women who prefer meat and fish in their diet more often give birth to boys, as well as those who actively engage in sports.
However, there were no clear theories confirmed in practice: the probability was about 50%. Now scientists hope that they have found the answer: they published the results of their work in the new edition of the American Journal of Hypertension.
The founder of the new theory was Professor Ravi Retnakaran, an endocrinologist representing the Canadian Hospital Sinai Health System (Toronto). The co-authors of the project were employees of the Lunenfeld-Tanenbaum Research Institute.
Scientists began recruiting volunteer participants in 2009. More than 1,400 young Chinese women from the town of Liuyang (People's Republic of China) took part in the experiment.
All participants were at the stage of pregnancy planning. At this time, they underwent all necessary laboratory and instrumental studies to find a "hook". The women had their cholesterol, glucose, and triglyceride levels examined, and their blood pressure was monitored. As a rule, about 26-27 weeks passed from the beginning of the experiment to the beginning of pregnancy.
As a result, the participants gave birth to 739 boys and 672 girls.
The experts summed up the results and found that one clear factor that was observed in women and determined the sex of the baby was blood pressure: those participants whose blood pressure readings were high were more likely to become mothers of boys.
The experts also assessed the influence of other factors: the participants' age, level of education, presence of bad habits, waist size, body mass index, content of low- and high-density lipoproteins, level of total cholesterol and glucose, etc. were taken into account. However, only blood pressure indicators were a common feature.
"This factor was not given much attention before: the assertion that arterial pressure can play such a role as determining the sex of the future baby was considered doubtful. We cannot find an explanation for how exactly this factor influences. Most likely, we will need additional experiments to verify our assumption," - such comments were received from Professor Retnakaran.