How soul is transferred into female body?
Although one may be promoted to a higher planetary system such as Candraloka, one must again come down (ksine punye martya-lokam visanti). After one’s enjoyment due to pious activities is finished, one must return to this planet in rainfall and first take birth as a plant or creeper, which is eaten by various animals, including human beings, and turned to semen. This semen is injected into the female body, and thus the living entity takes birth.
Source: A.C. Bhaktivedanta Swami Prabhupada (2014 edition), “Srimad Bhagavatam”, Seventh Canto, Chapter 15 – Text 50 & 51
