The gender of a baby can typically be found out during pregnancy through several methods:

• The most common time to find out the baby's gender via ultrasound is around 18 to 22 weeks of pregnancy during the anatomy scan, where the technician looks for sex organs.

• Some ultrasounds can give clues as early as 11 to 13 weeks using the "nub theory," but accuracy increases with gestational age.

• Noninvasive prenatal testing (NIPT), a blood test from the mother, can detect the baby's gender with high accuracy from about 10 weeks into pregnancy.

• The earliest blood tests for gender determination can be done around 6 weeks but are more accurate after 10 weeks.

• Diagnostic tests like amniocentesis or chorionic villus sampling (CVS) can determine gender earlier but are generally done for genetic testing and carry some risks.

So, one can find out the baby's gender reliably starting as early as 10 weeks with blood tests like the NIPT or by waiting until the routine ultrasound around 18 to 22 weeks.