Second Trimester: 12 to 24 Weeks
Visits every three to four weeks, much like the routine visits of the first trimester, except with the addition of listening for fetal heart tones:
- You'll be offered the alpha-fetoprotein (AFP) screen (or triple screen) between weeks 15 and 20. During this time, your doctor will also determine fetal growth by serial fundal height determinations. If you've not enrolled in prenatal classes at your hospital or through private instruction, check with your doctor for good recommendations.
- You'll have a cervical cerclage if it's needed (the optimal time is 14 weeks if there's a threat of incompetent cervix).
- The second trimester is the best trimester in which to have any necessary surgery, such as gall bladder surgery.
Third Trimester: 24 Weeks to Delivery
- Between weeks 24 and 30 weeks, you'll visit your doctor every two to three weeks.
- At around 26 weeks expect a glucola screen for gestational diabetes.
- At around 28 weeks you'll have a group B strep vaginal culture, and your doctor will discuss signs of preterm labor and begin monitoring if indicated.
- At 32 weeks your doctor will try to determine fetal position (this is the time a baby usually locks into position). A suspected breech baby in the third trimester can be a cause for concern and will usually necessitate an ultrasound.
- At 36 weeks you'll begin weekly visits or even more frequent visits if you're experiencing a high-risk pregnancy. Your doctor may offer version of an abnormal position, or breech, to help move the baby into a vertex (head-first) position.
- At 37 to 38 weeks you may begin weekly cervical checks.
- At 39 weeks your doctor can now offer induction if your cervix is ripe.
- Once you're at 40 weeks you're full term! If you've not yet had your baby, expect to begin post-dates surveillance and more frequent office visits; your doctor may offer induction if your cervix is ripe.
- At 41 to 42 weeks you'll continue to receive post-dates surveillance.
- Once you reach 42 weeks, expect to be induced. Although most doctors differ somewhat as to which point indicates mandatory delivery, 42 weeks seems to be a dividing line where further waiting begins unacceptable risks.
Throughout your entire third trimester your doctor will keep a heightened vigilance for diseases and complications unique to pregnancy and watch you very carefully.