When your third trimester of pregnancy finally arrives, it can feel like your to-do list is already miles long: nursery prep, baby shower thank-you notes, writing a birth plan (and a postpartum plan!), not to mention all the now more-frequent appointments with your birth provider to ensure everything is moving along smoothly. In between keeping track of kick counts and pre-washing bottles, it’s so vital to squash stress and soak up this sweet time, but there are a few more to-dos to add to your list: getting your most pressing questions answered by your birth provider, including about third-trimester vaccinations, which are critical for protecting your newborn after birth.

Because babies’ immune systems are still developing, they’re not eligible for many childhood vaccinations at birth. This vulnerability makes maternal vaccination during pregnancy crucial for protecting newborns against certain preventable viral illnesses. Getting vaccinated toward the end of pregnancy serves a dual purpose: you’re providing your baby with vital protection while they’re in utero and continuing that protection after they’re born. This strategy, known as maternal immunization, creates a protective shield for your newborn during their most vulnerable period. 

The antibodies you develop in response to vaccination can cross the placenta, effectively arming your baby with a temporary but powerful immune defense. This passive immunity can last for several months after birth, bridging the gap until your baby can receive their own vaccinations. (The timing of maternal vaccines is carefully chosen to maximize this antibody transfer to the fetus.) Additionally, if you choose to breastfeed, you’ll likely transfer some antibodies through your breast milk, further bolstering your baby’s immune system. 

We spoke with Hasra K. Snaggs, MD, MPH, FACOG, Director of Vaccine Clinical Research and Development at Pfizer, who leads clinical studies on maternal immunization, to share more about which third-trimester vaccinations you should consider, along with other questions to get answered during these last few months before your baby arrives. As always, if you have questions about your unique pregnancy and health history, be sure to bring them up with your birth provider. 

8 important questions to ask at your third trimester appointments

The third trimester begins at week 28 and lasts until 40 weeks (or when you give birth!). Here are questions to write down in advance and bring with you to your third trimester prenatal appointment. 

1. Which tests are typically done in the third trimester?

Around the start of your third trimester, your provider will likely recommend you get a glucose screening test to check for gestational diabetes, says Dr. Snaggs, along with a standard blood panel to check for iron deficiency anemia (which is common in pregnancy) and your blood type. 

“Between weeks 35 and 36, routine blood work may include testing for sexually transmitted infections (HIV, syphilis, gonorrhea and chlamydia), an evaluation of your urine to check for infection, as well as a vaginal and rectal swab (culture) which is taken to screen for group b streptococcus (GBS), a bacteria that is commonly found in the vagina and GI tract but can pose a risk to infants at birth and up to 90 days after birth,” she notes. If you test positive, you may need to take antibiotics at the time of labor to protect the infant from infection. 

2. What vaccines should I get before my baby is born? 

The Centers for Disease Control and Prevention (CDC) and American College of Obstetricians and Gynecologists (ACOG) recommend certain vaccines during pregnancy to protect both you and your unborn baby against illness, as Dr. Snaggs explains. She tells Motherly, “A benefit of maternal immunization is that you help protect your baby from day one, as babies’ immune systems cannot mount an adequate immune defense against infections until they are older.”

In the US, the CDC recommends four vaccines during most pregnancies: Tdap, Flu, Covid, and RSV. Dr. Snaggs notes, “Other vaccines may also be recommended in some circumstances,” so it’s important to discuss with your doctor what’s necessary for your specific situation.

Maternal vaccines are typically administered in the third trimester because, as Dr. Snaggs explains, “Vaccines cause your body to make antibodies that can prevent certain viruses and bacteria from entering the cells in your body. And some of these antibodies can pass to your unborn child, protecting against disease after birth.”

The timing of these vaccinations is crucial for optimal protection. Here’s a general guide on when to get which vaccines:

Tdap vaccine: Between 27 and 36 weeks

  • Aims to prevent whooping cough
  • Grandparents or other close relatives who will be in contact with the infant are advised to get a Dtap booster close to the baby’s due date, too

Maternal RSV vaccine: Between 32 and 36 weeks

  • Pfizer’s Abrysvo maternal RSV vaccine is recommended seasonally between September and January
  • Protects babies against RSV from birth through 6 months of age. “This is when babies are at the highest risk of severe RSV disease and complications; a time when they’re the most vulnerable,” Dr. Snaggs shares.

Covid vaccine: Anytime during pregnancy

  • The CDC notes that pregnant women are more likely to get very sick from Covid compared to those who are not pregnant with an increased chance of complications affecting both the pregnancy and the newborn, says Dr. Snaggs. Vaccination is one of the best ways to protect yourself and your baby against severe disease.
  • Recommended for everyone aged 6 months and older, including pregnant people
  • Can be administered at any stage of pregnancy

Flu vaccine: Anytime during pregnancy when it’s flu season

  • Recommended during flu season (October to May)
  • Important note: Pregnant women should discuss the advantages and risks of vaccination with their healthcare providers early in pregnancy to address any questions or concerns

3. What should I know about creating a birth plan? 

Going into your labor and delivery with a general knowledge of your birth preferences can be helpful so you’re not caught off-guard if any unexpected issues arise. Creating a birth plan can help some expectant parents feel like they have some control over the process—with a document to point to—but it’s important to not get super attached. The best birth plans have some flexibility built in. “Starting a conversation early around your birth plan is important so that expectations can be clear, with the understanding that changes may occur to protect mother and baby,” Dr. Snaggs says. The key? “Having meaningful discussions with your healthcare provider” to ensure you feel comfortable and supported throughout. Reviewing a birth plan in your third trimester appointments with your provider in advance can help everyone get on the same page. 

4. How often should kick counts be done?

Love feeling those tiny (but forceful!) baby kicks? Kick counts can be used as a tool for pregnant parents to evaluate fetal movement. ACOG says kick counts can be used to evaluate the general well-being of their developing fetus. Dr. Snaggs points out that there are several protocols available, including one that looks for 10 distinct movements over a 2-hour period, but that you should seek guidance from your birth provider on what they specifically recommend you look out for. 

5. What are the signs of early labor?

“Women are considered to be full-term starting at 37 weeks of pregnancy,” Dr. Snaggs explains. “During your prenatal visits, your provider may guide you on the signs and symptoms of labor, which includes regular painful contractions and/or the rupture of your amniotic sac [known as your ‘water breaking’] with increasing dilation and effacement of your cervix.” If these set in before 37 weeks, it’s considered early labor, and you should seek medical attention. 

“Sometimes, women can have false labor pains or Braxton Hicks contractions, so it is important to check with your provider if you believe that you may be in labor,” she suggests, as they can help you determine the difference between Braxton Hicks and true labor contractions.  

6. What are the third-trimester signs that might mean something is wrong with my pregnancy?

“Preparing for the arrival of your baby is an exciting time,” Dr. Snaggs says, “But your provider may discuss times that you may need to obtain immediate care, for example if you experience heavy vaginal bleeding, significant abdominal pain, a change in your baby’s movements or elevations in your blood pressure.” Essentially, trust your gut. If something doesn’t feel right or seems different than what you’re used to, reach out to your provider right away.   

7. What should I know about postpartum?

“Postpartum care is just as important as the care that you receive during pregnancy and during labor and delivery,” reminds Dr. Snaggs. She recommends having a discussion with your doctor or midwife about what you can expect during your time in the hospital or birth center immediately following birth. You’ll need at least 6 weeks of physical recovery time after birth (or longer, depending on your delivery—and some docs now recommend 12 weeks), during which your physical activity will need to be limited. Will you need extra hands during this time? Ask for their recommendations for how to include and involve family members, which can be especially helpful.

Similar to how you created a birth plan, it’s important to sit down with your partner and map out a postpartum plan, too. What will night shifts look like? Will you start pumping right away? Where will the baby sleep for the first few months? Who will be responsible for taking care of other responsibilities, like older kids and pets? Planning this out in advance can help open the door for clear communication about your needs down the road.  

8. Will a lactation consultant be available in the hospital or birth center?

Similarly, don’t forget to ask about what resources will be available to you right after birth. As you embark on your feeding journey with your infant, will a lactation consultant be available to you, or does your birth provider have references they can share? Do they recommend you meet with a lactation consultant before birth to talk through important information and gain a basis of understanding around breastfeeding? Do they suggest you keep a can of formula on hand just in case? Now’s a good time to ask any questions you may have around feeding, especially if it’s your first baby. Remember, your healthcare provider is there to be a resource for you—so ask all the questions.