Final answer:
Prostaglandin can be used effectively for inducing abortion within a certain number of days post-breeding, with the timeframe determined by species-specific gestational periods and ethical, legal, and medical standards. In humans, hormonal changes that reset the menstrual cycle naturally involve prostaglandins if pregnancy does not occur within 10 to 12 days post-ovulation.
Step-by-step explanation:
The use of prostaglandin for inducing abortion is a practice that can be effective within a specific timeframe after breeding or conception. In humans, if pregnancy does not occur within 10 to 12 days post-ovulation, the corpus luteum will degrade, leading to a decrease in hormones such as progesterone and a subsequent period, indicating the onset of a new menstrual cycle. However, when discussing the effectiveness of prostaglandin in terminating a pregnancy, one must consider the legal, ethical, and medical guidelines which vary by jurisdiction. Emergency contraception can be taken within days of unprotected intercourse and is considered distinct from the usage of prostaglandin for abortion purposes.