What’s considered CD1?

Alisha • 35 years old 🐕 Wife + Dog Mama | UI | IVF ❄️ 7 frozen embabes | 6 MC’s

Should I count spotting or first sight of blood CD1? I’m supposed to start Clomid on CD5 and had very faint spotting yesterday and a bit heavier today but barely enough to fill a tampon. What are your thoughts?

Thank you!