Navigating Pregnancy: Prenatal Screenings and Vaccines

Pregnancy
Written By Jessica Burrus

Last updated April 2025.

First Trimester: Early Pregnancy Tests & Decisions >

NIPT (Non-Invasive Prenatal Testing) >

Second Trimester: Early Pregnancy Tests & Decisions >

Vaccinations During Pregnancy >

Third Trimester: Early Pregnancy Tests & Decisions >

Resources >

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Congratulations! This is a very exciting and overwhelming time for you and your surrounding loved ones. Whether this is your first or sixth child, you have the ability to make different choices for each pregnancy. I made some changes during my third pregnancy that were right for me and my family, and I’m very fortunate to have had the resources that I had to help me make those decisions. My hope is always to gather resources in a summary for anyone else who is interested. This blog will touch on the general/common prescreens and tests used during a healthy pregnancy.

Please know that I am not a medical professional. The resources I am bringing you are researched and scientifically backed, but can never replace the advice of your doctor or medical team.

First Trimester: Early Pregnancy Tests & Decisions

In my experience, the earliest an office will schedule an appointment is six (6) weeks from your last period. Most commonly, I have seen the standard to be eight (8) weeks. At that first appointment you’ll likely do a urine culture. You’ll likely do a urine culture almost every appointment. A urine culture is a test that identifies bacteria that you may not know are there. A urinalysis regularly helps to monitor signs of UTIs, diabetes, and preeclampsia [2].  Typically, they are looking for things that are signs of infection or complications [4]. I’m not aware of any types of risks or complications associated with providing urine samples for those types of tests. 

In your first trimester you will do a blood draw for an initial screening. A complete blood count (CBC) measures different cells that make up your blood. The screening can show indicators of anemia, your body fighting a disease, or clotting. It’s also important to find out your blood type as an RH negative status leads to treatment to prevent Rh antibodies [2]. Typically, first trimester blood screening also looks for a host of infectious information like if you have any infections that may harm your growing baby, or if you have immunity to some infections [7]. There are no known risks to getting your blood drawn for the first trimester screening tests other than discomfort for some people [5].

Carrier testing is often offered during your first pregnancy, and then as long as you know or keep your results you can make decisions whether to get it again with subsequent pregnancies. The blood test looks at your blood to see if you are a carrier of hereditary/genetic diseases [4]. I’ve been advised to take the test, and then only get my partner involved if I was found to be a carrier for any disease. I’ve had three babies with the same partner, so I did not opt to do the carrier testing for my second and third babies. 

The last screening in the first trimester is an ultrasound. I personally find ultrasounds very exciting any time I get a chance to have one. During first trimester ultrasounds they are looking for confirmation of a due date, the number of babies in there, a healthy and normal attachment and your anatomy for any abnormalities [1].

NIPT (Non-Invasive Prenatal Testing)

The NIPT (Non-invasive Prenatal Testing) test also known as cell-free fetal DNA testing is an optional screening you can have done through a blood draw any time after nine (9) weeks [4]. The screening looks for genetic conditions such as down syndrome and is the infamous blood test that provides details of the baby’s gender. Since the NIPT test is questionable as necessary with some insurance companies the price and availability of the tests can be confusing. There is a resource below about this test specifically.

Second Trimester: Early Pregnancy Tests & Decisions

Back to blood tests, the maternal blood screening (quad screening) is an option offered in your second trimester. It is able to check the baby’s blood for signs of some birth defects [4]. 

Your big anatomy ultrasound scan is done in the second trimester. Referred to as the 20 - week anatomy scan, that ultrasound is around an hour and will look in depth at the baby, all their parts and organs, blood flow and placenta health, and growth [1]. This scan will often result in photos. Sometimes you have to ask for them. I’ve also had to ask if 3D was available and if we can have certain photos printed. Don’t be afraid to ask, the worst anyone can do is say no. 

Another well known screening that takes place in the second trimester is the glucose test. The first screening and hopefully only one you will need is a one hour test where you drink something and then get your blood drawn one hour later to measure your blood sugar levels done between 24 and 28 weeks [7]. This test screens for gestational diabetes [2]. The substance you have to drink has gotten a bad reputation for the contents and The Fresh Test is now much more available and given as an option. It’s most known for being vegan, having no additives, and being a healthier alternative overall to the Glucola drink. With my third pregnancy in 2024 I had the option through my practice. My good friend did not, and ordered it on her own and did her blood draw directly through LabCorp.

I want to preface this section by saying I’m not going to touch the vaccination debate with a 10-foot pole. My goal here is to give all the information I can find so that YOU can make the best decisions for YOU. I’m sticking it in between the second and third trimester sections, because that is typically when you will be asked about receiving them.

Why even get a vaccination while pregnant? What are the pros? The antibodies that the mother develops with a normal response to a vaccine crosses the placenta to also help protect your baby from the illnesses that the vaccination addresses early on before they can get their own protection through vaccinations [6]. The current recommendation from the CDC is the flu vaccine and the Tdap vaccine. The CDC clearly states the following vaccines SHOULD NOT be given while pregnant [6]:

  • HPV

  • MMR

  • Nasal flu

  • Chicken Pox

  • Yellow Fever

  • Typhoid Fever

  • Japanese Encephalitis

  • Live vaccines

Third Trimester: Early Pregnancy Tests & Decisions

With the last trimester comes the minorly controversial Group B Strep (GBS) test. This is a swab of BOTH holes, yes, don’t be surprised. They swab your vaginal canal as well as the outside of your butt hole for any indication of the Group B Strep infection [4]. It is NOT an STI, and usually you wouldn’t know that you have it [3]. Although rare, if positive at the time of birth a newborn COULD be transmitted GBS during labor [2]. It’s a swab late in pregnancy, I didn’t mind it, but some are uncomfortable with the quick procedure. The biggest controversy that surrounds GBS is the treatment and when it is tested. The CDC recommends you get tested after the 36th week of pregnancy as close to potential delivery as possible. The reason for that being you can test positive for GBS, and then two weeks later be negative. It does come and go naturally in your body as an adult [8]. 

The result of a positive GBS test is antibiotics during labor to the mother to help prevent the possibility of the newborn baby getting sick from anything that may pass on to them through a vaginal delivery. With my second I had a GBS test completed at a 37 week appointment and then went into labor four (4) days later at which time we didn’t have the results of the test yet. They were able to do a swab at the hospital and get rapid results to make sure I wasn’t positive at that moment. While antibiotics can be lifesavers, in my non-medical experience they are prescribed far too often. Not only do they wipe out infections and save lives, but they also disrupt the gut microbiome and functions within your body.

An ultrasound will also be done in the third trimester closer to delivery time. This ultrasound is done to look at fetal growth, check the amount of fluid, and see what position the baby is in [1].

Resources

  1. A free visual aid to keep it all straight.

  2. The Fresh Test. I seriously love this alternative.

  3. Join the email list for updates and new information as it’s released!

  4. Check our social media pages linked below for more info!

As always, I’m here to share my experiences, facts, and resources in a non-judgmental way so you can make the most informed decisions for yourself and your family. Your choices are personal, and my goal is to simply provide support on your journey.

The information provided in this article is for informational purposes only and should not be considered as medical advice. I am not a licensed healthcare provider. Always consult with a qualified doctor or healthcare professional before making any changes to your health, diet, or wellness routine.

Jessica Burrus

MEd, mom of three

Next

The Ultimate Guide to Prenatal Vitamins: Essential Nutrients Every Expecting Mama Needs!