You had a scan done at the hospital and sono said you were 6 weeks pregnant but then went to your doc he 4-5 y would this be?

There are a few possible explanations for this difference in gestational age estimates:

- Variability in early pregnancy dating: Early pregnancy dating can be challenging, especially in the first few weeks, due to factors such as differences in menstrual cycle length and variation in embryonic development. Sono at week 6, and doctor's estimate of 4-5 weeks may simply reflect this natural variability in early pregnancy dating.

- Measurement differences: The gestational age estimated by the sonologist and the doctor may be based on different measurements or methods. For instance, the sonologist may have measured the crown-rump length (CRL) of the embryo, while the doctor may have used a different parameter such as the size of the gestational sac.

- Potential errors in calculation: There is always a possibility of human error or miscalculation during the estimation of gestational age, both in the sonographic measurement and the doctor's assessment. Factors like the quality of the ultrasound images and the experience of the healthcare professional can influence the accuracy of these estimates.

- Rarely, it could indicate a condition called embryonic demise or missed abortion, where the embryo stops developing but the pregnancy continues to progress. In such cases, the sonographic measurement taken earlier in week 6 may have captured a slightly more advanced stage of development that the embryo eventually did not reach.

Given these possibilities, it's important to discuss these differing gestational age estimates with your doctor. They will be able to provide you with a more personalized explanation based on your individual circumstances and may recommend additional tests or scans if necessary to clarify the gestational age and ensure your pregnancy is progressing as expected.