Sy datang period,
bulan oct/2019 - 29hb
bulan nov/2019 - 25hb
bulan dec/2019 - 27hb
Sy ingat cycle sy 28.
Tp bila sy perhatikan waktu subur sy mcm bertukar2. Sbg contoh bulan dec. Kalau sy kira cycle 28. Means subur sy 10jan2020. Tp kalau sy kire cycle sy 32. Means subur sy utk bulan ni 15jan2020. Adakah sy patut tukar waktu cycle dlm calendar. Supaya sy dpt date waktu subur sy?
Mohon bg pendapat.