Week 1 Size: Not yet conceived
The journey is just beginning.
Relative Visual Scale
Solid circle represents your baby's size. Dotted circle shows the full-term week 40 size threshold.
Baby's Development
This week is actually your menstrual period. Although you are not technically pregnant yet, your body is preparing for ovulation. The cycle of egg development begins now.
Weekly Milestones
- ✦ Cycle Start
Your Body & Symptoms
You are experiencing your period. Your uterus is shedding its lining from the previous cycle in preparation for a new potential pregnancy.
Common Symptoms this Week
Doctor & Care Recommendations
- ✓ Start taking a prenatal vitamin with at least 400 mcg of folic acid daily.
- ✓ Track your cycle length to estimate your ovulation window.
- ✓ Avoid smoking, alcohol, and unnecessary medications.
Weekly Health Guides & Resources
First Trimester Guide
Read comprehensive clinical milestones, screening checklists, and developmental guidelines for this phase.
Track & Relieve Symptoms
Learn why symptoms occur, home remedies, and clinical indicators for this week:
Food Safety Checklists
Verify safety statuses, listeria and mercury risks, and safe alternatives for:
Frequently Asked Questions: Week 1
Get weekly pregnancy updates
Sign up to receive developmental milestones, medical symptoms, and expert tips tailored to your specific week of pregnancy.