From Positive Test to Birth

You're pregnant. Now what?

Three phone calls start everything: your OB or midwife (book the first prenatal visit as soon as the test is positive source), your insurance (what's covered, which hospitals are in network), and, later in pregnancy, a pediatrician for the baby (yes, you pick one before birth; see Building Your Village).

The visit rhythm for a typical low-risk pregnancy: about once a month until 28 weeks, every two weeks until 36, then weekly until birth, and more often if you're 35+ or high-risk. source source

First trimester (to ~14 weeks)

The first visit is the long one: a full blood panel (blood type and Rh, blood count, immunity and infection screens, urinalysis), a pelvic exam, your history, and prenatal vitamins with iron if you're not already taking them. A dating ultrasound (often transvaginal this early) sets your official due date. source

Optional genetic screening happens on a clock, so decide early: cell-free DNA (NIPT) from about week 10 source, and the nuchal translucency ultrasound + blood screen at weeks 11–14. source These are screens, not diagnoses — your provider will explain the follow-up options if anything is flagged.

Second trimester (14–28 weeks)

Usually the good part: energy returns, nausea fades, and you start to show. The medical calendar:

• ~20 weeks: the anatomy scan. The big ultrasound checks the heart, kidneys, spine, and limbs, plus the sex if you want to know. source
• 15–22 weeks: quad screen blood test, if you're doing it (most accurate 16–18 weeks). source
• 24–28 weeks: glucose screen for gestational diabetes. The famous sugary drink, then a blood draw. An abnormal result just means a longer follow-up test. source
• ~28 weeks: if your blood type is Rh-negative, a RhoGAM shot. source

This is also the sweet spot to book a childbirth class (aim to finish before the due date; your labor coach should come too source), tour the hospital, and start the registry while you still have energy.

Third trimester (28 weeks–birth)

• Tdap vaccine, 27–36 weeks (earlier in the window is better): your antibodies cross to the baby and cut whooping-cough risk in babies under 2 months by 78%, and babies get no shots of their own until 2 months. source
• RSV protection: either a maternal RSV vaccine at 32–36 weeks (September–January in most of the US) or an antibody shot for the baby after birth. Families choose one; ask your OB which fits your timing. source
• Group B strep swab, week 36–37. Painless swab; if positive (common, and no danger to you), you get IV antibiotics during labor to protect the baby. source
• Movement matters. The baby should keep moving daily right up to birth, and "babies slow down at the end" is a myth worth ignoring. If movement seems reduced: have a snack, lie down on your side, and pay attention. If it still seems quiet, call. Don't sit on it overnight. source
• Car seat, installed and checked, well before the due date. The AAP says to sort the car seat out before birth, and certified technicians will check your installation for free (details in Gear). source
• Hospital bag: there's no official week, but convention says have it ready by ~36 weeks, because babies keep their own schedules. Chargers, snacks, going-home outfits for both of you, your ID and insurance card, and the installed car seat cover most of it.

Is this labor, or a false alarm?

Braxton Hicks "practice" contractions can start any time after the first trimester: typically short, irregular, not painful, and they fade if you move, rest, or drink water. source

True labor doesn't care what you do: contractions come at regular, shrinking intervals (around every 5–10 minutes), last 30–70 seconds and get longer, radiate to your lower back and upper belly, and intensify until you can't talk or laugh through them. source

Losing the mucus plug can precede labor by days, which is interesting but not an emergency. Water breaking (a gush or a steady trickle) is a call-now event. source

For calibration: a typical first labor runs ~12–19 hours of first stage, 20 minutes to 2 hours of pushing, and 5–30 minutes for the placenta. source

When to call your OB or midwife