The baby's sex is genetically determined. Everything is decided at the moment of conception when the woman's egg meets the man's spermatozoon .
Sexual chromosomes X or Y determine the sex of the baby. Since all the eggs carry the X chromosome, it is the spermatozoon - the carrier of the X chromosome or the Y chromosome - that is decisive.
During conception, the chromosomes, therefore the DNAs, of the two cells (ovum and spermatozoid) unite. The chromosomes, therefore the DNAs, of the two cells unite.
This is the 23rd pair of chromosomes that determines the sex of the baby:
- XY for a boy. An X chromosome brought by the ovum of the mother, the Y chromosome brought by the spermatozoon of the man.
- XX for a girl . An X chromosome brought by the ovum of the mother, the X chromosome brought by the spermatozoon of the man.
How does baby grow up in the belly?
How many weeks of pregnancy can you see baby's fingers? How much does it weigh in the 5th month? And when is he able to discern the flavors?
Test your knowledge!
Then, during the development of the embryo, the organs will gradually be put in place. The external genitalia will differentiate progressively. It is generally towards the 15th-16th week of amenorrhea, that the sex of the fetus will be visible on the ultrasound.
The differentiation of the genitals is under the influence of fetal hormonal secretions, mainly under the influence - or not - of the male hormone secreted by the testicle in the future boy; and of course not secreted in the future girl.
At birth, in a very small percentage of babies, there are anomalies of genital development that will require the intervention of specialist pediatricians.
To see: ultrasounds during pregnancy in video
Throughout pregnancy, fetal development can be monitored by regular ultrasounds. Ultrasound is an examination that examines internal anatomy using high-frequency sound waves. Explanations in video ...You want to react, to give your testimony or to ask a question? See you in our FORUMS Getting pregnant, Pregnancy or A doctor answers you !
Read also :
> All about fertilization
> In Vitro Fertilization (IVF)
> The best chances to get pregnant