CRL(Crown Rump Length) varies from week by week and also day by day. A good increasing CRL means your baby is growing as expected without any issues. The normal CRL at 7 week ranges anywhere from 8mm to 15mm!
As per the Intergrowth table, the Normal CRL (Crown Rump Length) at 7 weeks 5 days or 6 days should be above 15 mm and it also differs according to percentile.At the beginning of 7th weeks, the foetus should be above at least 8mm and by the end of 7th week, the foetus can range anywhere from 15-17mm
| Gestational Age | CRL (in mm) |
|---|---|
| 7 Weeks 0 days | 8.0 – 9.0 mm |
| 7 Weeks 1 days | 9.5 -10.0 mm |
| 7 Weeks 2 days | 10.5 – 11.0 mm |
| 7 Weeks 3 days | 11.5 – 12.5 mm |
| 7 Weeks 4 days | 13.0 – 13.5 mm |
| 7 Weeks 5 days | 14.0 – 15.0 mm |
| 7 Weeks 6 days | 15.5 – 16.0 mm |
If the baby is measuring higher than these CRL mentioned in the above table, you need not worry as there is a chance that CRL measurement might be wrong (or) your ovulation date and LMP might have been miscalculated!
References:
https://linkinghub.elsevier.com/retrieve/pii/S0301211509002383
https://intergrowth21.tghn.org/
https://www.hindawi.com/journals/isrn/2012/938583/tab4/