Give scientific reasons: Pregnancy can be stopped or prevented without artificial methods of family planning.

(N/A) Pregnancy can be prevented naturally by avoiding coitus during the fertile period of the menstrual cycle. The days between $10$ and $17$ of the menstrual cycle are considered the fertile period because ovulation typically occurs around the $14$th day. Avoiding sexual intercourse during this window prevents fertilization.
Additionally,Lactational Amenorrhea is a natural method based on the fact that ovulation and the menstrual cycle do not occur during the period of intense lactation following parturition. As long as the mother breastfeeds the infant fully,the chances of conception are negligible.