No, it is not. Sounds to me like your girlfriend has misunderstood how fertility cycles work. While cycles vary between people who menstruate -- which is part of why the "calendar method" isn't a good one -- a vast majority of those people will be most fertile mid-cycle, between around day ten and...
cycle
Advice
- Susie Tang
1. The hormones in birth control pills prevent the uterus from building up its lining (endometrium) as thick as it would be under a normal fertile cycle. This effect is mainly from the progesterone in the pills. Progesterone's function in the body is to maintain the endometrium in stasis, so that it...
Article
- Heather Corinna
What's the menstrual cycle? How does it all work? What are periods and options for managing them, and when's it time to check in with a healthcare provider?
