Seventy percent of the female fetuses are sterilized they are known as 'freemartins.' The fetuses undergo different treatments depending on their castes. The entire process is designed to mimic the conditions within a human womb, including shaking every few meters to familiarize the fetuses with movement. On the last day, they are 'decanted,' or born.

After fertilization, the embryos travel on a conveyor belt in their bottles for 267 days, the gestation time period for a human fetus.

The Director and Henry Foster continue to explain the processes of the plant to the boys. Henry Foster, an employee at the plant, tells the attentive students that the record for this particular factory is over 16,000 siblings. The average production rate using Podsnap's Technique is 11,000 brothers and sisters in 150 batches of identical twins. With this method, hundreds of related individuals can be produced from the ova and sperm of the same man and woman within two years. The Director goes on to describe Podsnap's Technique, which speeds up the ripening process of eggs within a single ovary. The cloning process is one of the tools the World State uses to implement its guiding motto: 'Community, Identity, Stability.' The Director explains that the Bokanovsky Process facilitates social stability because the clones it produces are predestined to perform identical tasks at identical machines. The Alpha and Beta embryos never undergo this dividing process, which can weaken the embryos. Gamma, Delta, and Epsilon undergo the Bokanovsky Process, which involves shocking an egg so that it divides to form up to ninety-six identical embryos, which then develop into ninety-six identical human beings. The five castes are Alpha, Beta, Gamma, Delta, and Epsilon. The Hatchery destines each fetus for a particular caste in the World State. Instead, surgically removed ovaries produce ova that are fertilized in artificial receptacles and incubated in specially designed bottles. He explains to the boys that human beings no longer produce living offspring. The Director of Hatcheries and Conditioning is giving a group of students a tour of a factory that produces human beings and conditions them for their predestined roles in the World State. The novel opens in the Central London Hatchery and Conditioning Centre.

Sparknotes brave new world chapter 18