A: Your practitioner is checking the growth of your baby by measuring from the top of your pubic bone to the top of your uterus. As your pregnancy progresses, this distance should continue to increase. We use the metric system in obstetrics, so the measurement in centimeters usually correlates with the number of weeks you're pregnant after the 20th week of pregnancy. In other words, a 25-centimeter measurement is expected of a woman who's 25 weeks pregnant. Your doctor uses this measurement to monitor the growth of the baby. If this number slows down, he or she may suggest further testing.