I thought you would know it but you can find NEOG in 'Manusmriti'.
NEOG is an ancient Hindu religious custom initiated by the only Hindu philosopher and Guru of ancient India, MANU (2000 BC). He wrote the Sanskrit text 'Manusmriti'.
A husband of weak constitution would send his wife to live with a strong man for 40 days hoping to procure a healthy child.
SATEE and NEOG are still being practiced in some parts of India, especially in Rajasthan, Assam, Haryana and Kerala.