if your baby is measuring big will it come early?

What Does It Mean if Baby Is Measuring Big?
Here's what to know if your practitioner tells you that you're "measuring big."

"I just came from my 32-week appointment, and my doctor says I measured 35 weeks. I'm afraid my baby will be too big to deliver vaginally."

Modern medicine can tell us a lot about how babies are doing before they're born and even what they look like. But guessing how big they are is just that — a big guess.
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In early pregnancy, you might be showing earlier for a few possible reasons, such as:

Muscle tone. A pregnant woman with looser abdominal muscles is more likely to produce a pronounced tummy than a mom-to-be with a very toned torso. That's also why expectant mothers who have previously given birth and whose abdominal muscles have already been stretched and loosened will tend to show earlier. Your body type might also be at play; some women carry their babies lower, which makes them appear to stick out more.
Miscalculated due date. Another common explanation for a seemingly supersized stomach is a miscalculation of the conception date. A 15- or 16-week tummy will certainly be larger than a 13-week one, so double-check your due date.
Bloating. Your big belly could also be caused by a bout of excess gas.
Twins. If you were earlier on in your pregnancy, there could be a chance you were carrying twins without yet knowing it: Many women who sport an impressive tummy in their first trimester later discover that they're having two babies. Before you start doubling up the layette, however, keep in mind that just as many women who popped early and became convinced they were carting around two babies turned out to be bearing just one. An ultrasound settles that question.

Later on in pregnancy, your baby is maxing out on the space available in your uterus, which makes his weight notoriously difficult to predict. A late-stage ultrasound estimate can be off by a pound or more — which makes a huge difference in a 5-pound baby!