It is not uncommon for there to be a discrepancy between the gestational age determined by ultrasound and the estimated due date (EDD) calculated based on your last menstrual period. Ultrasounds are more accurate in determining gestational age in early pregnancy, but as the pregnancy progresses, they can become less precise. The difference of two weeks between your expected gestational age and what was measured on the scan could be due to several factors.
Firstly, it's possible that you ovulated or conceived earlier or later than expected. This can happen if you have irregular periods or if there was a delay in implantation after fertilization. In such cases, the EDD calculated based on your last menstrual period may not align with the actual fetal development.
Secondly, growth spurts can occur at different rates for each individual fetus. Some babies may grow faster or slower than average during certain stages of pregnancy. This could explain why your baby appears to be measuring ahead or behind in terms of gestational age.
Lastly, errors in measurement during the ultrasound can also contribute to discrepancies in gestational age determination. Factors such as positioning of the baby, technician experience, and equipment calibration can all affect the accuracy of measurements taken during an ultrasound.
It's important to note that a small difference in gestational age does not necessarily indicate any problems with your pregnancy. However, if there is a significant difference between your expected EDD and what was measured on the scan, your healthcare provider may want to monitor your pregnancy more closely. They may recommend additional ultrasounds or other tests to ensure that your baby is growing and developing properly.
If you have any concerns or questions about the discrepancy in gestational age and EDD, it's best to discuss them with your healthcare provider. They will be able to provide personalized guidance based on your specific situation and medical history.