The heart is almost completely developed and the heart rate can be heard on a Doppler machine at the doctor's office.

Most major organs and tissues have developed and red blood cells are now produced in the liver. The face is well formed and the eyes are almost fully developed. The eyelids will close and not reopen until the 28th week. Arms, hands, fingers, legs, feet, and toes are fully formed. Nails and earlobes start to form and tooth buds develop in the gums. Fetus can make a fist with its finger. Testosterone (male sex hormone) is produced by the testes in male fetus.