When will my baby come?
Unless you have a history of preterm labor or complications, most OB providers will begin checking your cervix at your prenatal appointments around 36 or 37 weeks. It depends on the circumstances. And after being examined, a lot of women go home and wonder "Well, what did that exam mean, and when am I going to have my baby?", because maybe your doctor told you you were 2 centimeters or something and you wonder if you're going to deliver soon. And really, there is no good way to tell when a woman is going to deliver, because there are some women who are checked in the office in the morning, and they're 1 centimeter dilated, and then they end up delivering that night. And then there's others who are checked in the office, and they're 3, 4, even 5 centimeters, but they're not regularly contracting, the doctor tells them to go home and to watch for regular contractions, and they stay pregnant for weeks. And so there really is no good way to tell.
The best sign you have that you're in labor is that you're contracting regularly and intensely. It'a all about regular and intense contractions. And actually, in the days to weeks leading up to the delivery of a baby (this is under ideal circumstances), a woman's body will begin to release hormones called prostaglandins that act on the cervix and ripen it just like a fruit. And it softens the cervix, moves it forward in the woman's pelvis, and begins to thin it out. And the thinning out is called effacement, and so this is one of the things that a doctor will typically tell a woman about when he checks her cervix. They'll say you're 2 [centimeters] and you're 80% effaced. And the effacement is discussed in terms of percentages, and the higher the percentage, the thinner the cervix is.
So on the day that you got pregnant, your cervix is pretty thick, like almost the thickness of my finger, and then it starts to thin slightly, like around 28 weeks or so. But if it starts to thin too much too soon, then you're at risk for preterm delivery, so we don't want it to happen too early. But then, of course, towards the end and the weeks leading up to delivery, we want your cervix to thin out, because that's part of that ripening process. And it's not really thin until it's like 70%, 80%, 90% effaced. Before that, it's just still thick. And if your cervix hasn't softened, moved forward, and begun to thin out, and dilate a little bit on its own due to these hormone changes, then you could have all the contractions in the world and, likely, your cervix won't dilate. So the ripening has to happen first, and then the dilation happens as a result of these contractions. And if your cervix is dilating, or changing from hour to hour as a result of contractions, that's the true definition of labor.
So if you're having regular contractions (like every 5 minutes or so) and you're full-term, then it's time to go to the hospital and see if your cervix is changing. And upon arrival, the nurse would check your cervix, and as long as you're not like 6, 7, 8, 9, 10, or something like delivery is eminent, then they'll watch you for another hour. And during this time, they're watching the contraction pattern, the baby's heart rate pattern, your vital signs, collecting a lot of information, and then they re-check your cervix after an hour, and then call the doctor and tell them about their exam. And the doctor makes the decision about whether or not it's time to keep you, and that's based on whether or not there is cervical change and how everything else is looking.
You also need to go get checked out if you have any vaginal bleeding, any leaking of fluid from the vagina that makes you feel like your water has broken, and if you feel your baby move less than usual. And these are all reasons independent of each other. So in other words, if you feel like your water broke, but you're not contracting, you should still go in. Or if you're contracting every 10 minutes and you're full-term, it's not every 5 minutes yet, but you're having some bleeding or spotting, you should go get checked. Or if you're contracting every 8 minutes, not quite frequent enough to go in because of contractions, but you're not feeling your baby move as much as usual, then you should go in and get checked.
So back to the original question of "When are you going to deliver based on the exam your doctor gives you in the office?", there is no good way to tell, and you just need to watch for signs that you may actually be in labor. And if you're seeing those signs, then go to the hospital to get checked so you know for sure. Good luck with everything, and if you have more questions in the future for me, feel free to ask them on our Facebook page at / intermountainmoms , and recommend us to your friends and family too.