You and your partner have reached an exciting milestone. You'll have your first ultrasound around now and see your baby; this may help you feel closer to her. For many men, seeing the baby on the scan may be the first time the pregnancy becomes a reality.
At this scan, your baby's length will be measured (see You are 11 Weeks and 2 Days) and this will be used to figure out her age. Up until about 12 weeks of pregnancy, all babies grow at around the same rate so irrespective of whether you and your partner are tall or short, at this time your baby will be the same size as others at this stage of development.
Figuring out your due date (see When will your baby be born?) using the first day of your period, isn't always accurate, especially if your menstrual cycle is long or irregular. The dating scan can give a more accurate expected date of delivery, but it by no means tells you for certain-very few babies arrive on their actual due date.