Transcripción (en)

During ejaculation, approximately 300 million sperm travel from the testes through the vas deferens into the prostate. The prostate then contracts, releasing alkaline fluid to safeguard sperm in the acidic vaginal environment. Seminal plasma, containing nourishing sugars, remains in the vagina. Sperm navigates cervical mucus to reach the uterus, and fertilization typically occurs in the fallopian tube. The fertilized egg transforms into a zygote, rapidly dividing before journeying to the uterus. Upon reaching the uterine wall, the blastocyst embeds itself, prompting the ovaries to halt egg release. It progresses from a blastocyst to an embryo and eventually a fetus. Around weeks 9 to 12, distinct facial features emerge, and vital organs advance in development. The circulatory system, brain, and spinal cord take shape. By week 12, the fetus measures around 5 cm, weighs approximately 14 gris, and continues maturing until birth.