Monitorização da fertilidade: diferenças entre revisões

--><ref name="European">{{cite journal | title= European Natural Family Planning Study Groups. Prospective European multi-center study of natural family planning (1989-1992): interim results | journal=Advances in Contraception | year=December 1993 | volume=9 | issue=4 | pages=269-283 | id=PMID 8147240 }}</ref><!--

-->.<ref>{{cite journal | author=Frank-Herrmann P, Freundl G, Gnoth C, et al | title= Natural family planning with and without barrier method use in the fertile phase: efficacy in relation to sexual behavior: a German prospective long-term study | journal=Advances in Contraception | year=June-September 1997 | volume=13 | issue=2-3 | pages=179-189 | id=PMID 9288336 }}</ref>

 

== Conseguindo a gravidez ==