The medical world has a language all its own, and pregnancy dating might be one of its most confusing dialects.
Here's what's so confusing about it: When a doctor says, "4 weeks pregnant," your baby has actually only existed for about 1 to 2 weeks. Not 4. Strange as that may be, this gap is not a mistake or an oversight. It is simply how pregnancy has been dated since the 1800's, and it has everything to do with something called your last menstrual period, or LMP.
Nearly every doctor, midwife, and due date calculator uses a method called Naegele's rule, developed in the 1800s. It works like this:
•Take the first day of the last menstrual period
• Add 7 days
• Subtract 3 months
• Add 1 year
That formula lands you at your estimated due date.
This method assumes a textbook 28-day cycle with ovulation on day 14, something many bodies do not actually follow. It also does not account for irregular cycles, late or early ovulation, or uncertainty about cycle dates. Still, it remains the standard way pregnancy is dated, which means counting begins before conception even happens.
So by the time a missed period sends you reaching for a pregnancy test, you are already considered 4 weeks along, medically speaking. This is also why most chemical pregnancies are identified between 4 and 5 weeks, and why that number might show up on lab work or loss documentation.
Understanding this changes something. It means that even in the earliest losses, there is a medically recognized starting point.
That is exactly why our Gone So Soon Pendant Necklace begins at 4 weeks. Our keepsakes follow medical gestational dating by LMP so that what you hold in your hand lines up with your records, your timeline, and the little life you cherished.
And for the parents who have seen life begin and end through IVF, we can always create a custom design of your child's embryo here.
Because even the earliest loss deserves recognition of life ♡
