What your baby is more or less swimming in for nine months. When your water breaks, it's the amniotic fluid that gushes -- or more likely trickles -- out.
Halfway through pregnancy (somewhere around 20 weeks), you'll get this, also known as a level 2 ultrasound. It's your chance to find out if you're having a boy or girl! The sonographer also measures the baby's length and head size, and checks for the development of organs, such as the heart and lungs.
A document you write and then share with your doctor, explaining your preferences for the birth. Just don't think you'll always get what you want. My first birth plan called for a natural water birth with special music in the background. Ha! My second just kept reiterating what drugs I'm allergic to.
Thin milk, rich in proteins and antibodies, produced during pregnancy. Why would you ever see it? If your pregnant breasts... leak. Eeek!
Baby's umbilical cord has blood stem cells that could help someone else overcome a disease. You can pay (hundreds of dollars) to have it collected and stored for family members, or you can donate it to a public bank. Either has to be arranged in advance.
A Doppler fetal monitor picks up baby's heartbeat. Your doctor moves a handheld device across your belly until she finds a whooshing sound (your blood) and a horsey clip-clopping sound (baby's heart!).
The date that baby might arrive. Big emphasis on "might." It's not like baby has a calendar in there.
Imagine taking a cup of orange soda, boiling out most of the water, and then stirring in a tablespoon of sugar. This is what you drink to find out if you might have gestational diabetes. If there's an elevated amount of sugar in your blood an hour after you drink the stuff, you take a glucose tolerance test, which involves fasting and even yuckier syrup.
The top of your uterus is the fundus. When the doctor presses on your belly like she's making dough, she's looking for it. Then, in this high-tech world of 4-D sonograms, she'll pull out a regular old measuring tape and size you up as if to make some clothing alterations. What she's really checking is that you and the baby are growing at a good rate.
Peeing in your pants. Blame baby, who rests on your bladder.
"The dark line that's running from your belly button on down" must be too much of a mouthful, so it's named the linea nigra, Latin for "black line." It's actually always there, but (like your nipples) darkens considerably during pregnancy.
A thick blob of mucus plugs up the opening to your uterus. As your labor draws near, the plug might fall out. Most women never even see it (fortunately or unfortunately, depending on your level of squeamishness and interest).
During pregnancy, you grow not only a new human being but an entirely new and temporary organ, the placenta. This round, flat, blood-rich organ is how oxygen and nutrients flow from you to the baby, and waste and carbon dioxide flow from baby to you. One side of the placenta attaches to the wall of your uterus, and the umbilical cord attaches to the other. The placenta comes out shortly after baby does, and when you see it, you might be astonished at how huge it is.
In about 1 of every 200 women, the placenta either fully or partially covers the opening of the uterus, blocking baby's exit. There's a good chance that it will correct itself if you still have months to go. But if the placenta continues to cover the opening at the end of pregnancy, you'll have a cesarean birth.
Pregnancy-induced high blood pressure that's dangerous for you. It's why your doctor checks your blood pressure at every prenatal visit.
Doesn't this sound like cleaning a fish? Actually, it's a way to encourage labor. If you're overdue, your doctor can take her finger and run it around the inside of your cervix to detach the amniotic sac. Some women go into labor a few hours later; others (like me) can be stripped and, 10 days later, are still pregnant.
By the time you're reading this, you've probably already had it. It's a blood test done early in the second trimester that checks for chromosomal abnormalities and neural tube defects. But know this: A positive reading doesn't mean anything's wrong. It just means there's an elevated risk, and your doctor will want to discuss further testing.
These might be thrown at you during birth (because that's exactly when you want to be learning new vocabulary).
The baby's head is right there!
How wide your cervix has opened. Eventually you'll be 10 centimeters dilated, big enough for baby's head.
How to say this without scaring you? Sometimes even 10 centimeters is not enough, and the doctor, um, makes a little cut to help the baby through. You'll be too out of it to care.
This measures how baby drops down. She starts at -3 station, moves to zero when engaged in your pelvis, and is at +3 station when crowning.
Just do exactly what you do when you have to poop. Seriously. The same muscles shove baby out.
Number from zero to 10 indicating your newborn's brilliance. Kidding. It's just a quick judgment of his initial health, such as breathing and alertness; 7 to 10 is normal.
The thinning of your cervix in the lead-up to birth. You can be anywhere from zero to 100 percent effaced. But like so many early labor signs, it's pretty unreliable. Some women walk around 90 percent effaced for weeks before they give birth; others are not effaced one morning and yet give birth that evening.
If you go past your due date, your doctor might induce, or jump-start, your labor. It might involve breaking your bag of waters (forcing the amniotic fluid out), using a gel to ripen your cervix (making it efface), and/or giving you a drug called Pitocin, which starts contractions.
The baby is coming out feet first. These days, it usually means you're headed for a c-section.
Baby is supposed to be born facing your spine, but sometimes comes out "sunny-side up," which sounds cute, right? But it means the back of her head is hitting your spine, which means you may be asking for drugs.
When someone hands over your newborn and says, "Go to Mom," you can't believe the power of that little word.
Kerry Egan is a mother of two in Dartmouth, Massachusetts.
Originally published in the February 2009 issue of American Baby magazine.