Editing Calendar-based contraceptive methods (section)

===Destruction of fertilized eggs===
Philosopher Luc Bovens has suggested that the use of the rhythm method probably results in a large number of abortions, because unprotected intercourse in the infertile periods of the menstrual cycle may still result in conceptions but create zygotes incapable of implanting.<ref>{{cite journal |author=Luc Bovens |title=The rhythm method and embryonic death |journal=Journal of Medical Ethics |year=2006 |volume=32 |pages=355–356 |url= |doi=10.1136/jme.2005.013920 |pmid=16731736 |pmc=2563373 |issue=6}}</ref>  Bovens's argument requires the assumption that any and all destruction of fertilized eggs is abortion.