What you need is the option to "know your own body."

Fertility Cup
Fertility Support Cup - Timed Intercourse Support

Kegg
A fertility device that measures cervical mucus
Records changes in your body during ovulation using an app

[For fertility and pregnancy preparation]
Femiflora Folic Acid Plus
Daily base supplement that regulates from within with folic acid

【Iron Supplementation / Anemia Prevention】
Bear The Supplement Fe (30-day supply)
Nutritional support that easily replenishes the iron women need