You’re hearing a lot about what to expect throughout your pregnancy and you may have questions. What types of vaccines are necessary and normally given to pregnant women? Can the COVID-19 shot be administered safely along with other recommended shots? What routine tests do pregnant women need to stay as healthy as possible? And will my doctor talk to me about these? Dr. Hannah Ehasz, OB/GYN with Atrium Health Northeast Women's Health & Obstetrics Renaissance gives us the answers to some of our biggest pregnancy testing and vaccine questions.
Q: What types of vaccines should pregnant women get – and when should they get them?
During pregnancy, doctors recommend that pregnant women get these shots to protect against these illnesses that can cause significant harm:
- The flu shot (inactivated virus) is recommended every cold and flu season.
- The Tdap (Tetanus, diphtheria, acellular pertussis) booster is recommended during every pregnancy from 27-36 weeks—the earlier in this window the better. It helps protect the mom and baby from three illnesses that put pregnant women more at risk.
- The COVID-19 vaccine is recommended by multiple sources including the Centers for Disease Control (CDC), the American College of Obstetricians and Gynecologists (ACOG), and the Society for Maternal-Fetal Medicine (SMFM).
- For women with specific risk factors, physicians may also prescribe vaccines for:
- Pneumonia
- Meningitis
- Hepatitis A
- Hepatitis B
It’s also safe to administer flu, Tdap, and COVID-19 vaccines at the same time. However, since every woman’s health needs are different, the final say about which vaccines should be administered should come from her OB/GYN.
Q: Are Vaccines Safe for Pregnant Women?
Yes, vaccines are safe for pregnant women when they use the inactivated virus, bacteria, or toxoid. These have consistently been shown to be safe in pregnancy. Years of evidence show that the flu and Tdap vaccines do not increase the risk of miscarriage, adverse effects to the mom or fetus, or long-term developmental issues for the baby.
While data about the safety and effectiveness of the COVID-19 vaccine in pregnancy is limited, there is a growing body of evidence that the benefits of the vaccine outweigh any potential risks. Both animal and human studies have not identified any safety concerns for any of the available COVID-19 vaccines in any trimester. Studies have shown no increased risk for adverse pregnancy outcomes including miscarriage and congenital anomalies.
Q: How Do Vaccines Help?
Vaccines help by preventing disease or reducing the severity of many illnesses that could otherwise hospitalize a pregnant woman. Studies also suggest that vaccinated pregnant women pass protective antibodies through the placenta which protect the baby after delivery.
- Viral respiratory illnesses such as influenza and COVID-19 have more severe effects in pregnant women compared to non-pregnant women. Pregnant and postpartum women who contract influenza are more likely to develop pneumonia, need hospital admission and intensive care and have adverse outcomes for the pregnancy and baby. The flu shot protects pregnant women against several anticipated strains of the virus each year.
- Pregnant women with COVID-19 are at increased risk for intensive care unit (ICU) admission, need for mechanical ventilation (breathing tube or extracorporeal membrane oxygenation), and death. Some data also suggest increased risk for preterm birth and fetal death for women with COVID infection. The COVID-19 vaccine is proven to greatly reduce hospitalization rates among individuals infected with the virus.
- The Tdap offers protection against Pertussis (“Whooping cough”) is a highly contagious bacterial respiratory illness. Currently, the most important way to protect infants from whooping cough is through vaccination. While it can infect anyone, it is especially dangerous, and even deadly, for newborns less than one-year-old. Infants do not receive their first vaccine against whooping cough until two months old. However, when pregnant women receive a Tdap vaccine, they pass protective antibodies through the placenta which can protect the baby from the time of birth to full vaccination.
Q: What Vaccines Should Pregnant Women Avoid, and why?
Pregnant women should avoid any kind of vaccine with a live-attenuated virus. The Flumist vaccine, which uses a live-attenuated virus, is just one example. Others to be avoided are the MMR (Measles, Mumps, Rubella) and Varicella vaccine (chickenpox). These vaccines post a theoretical risk of infection to the pregnancy and are best avoided until after the postpartum period.
Q: What about certain tests during pregnancy? Which ones do pregnant women need?
There are several tests that your OB/GYN will recommend during your pregnancy care schedule. The pregnant woman’s age, health condition, and other factors influence whether one or all the tests are necessary. Here are the main tests that are offered and why.
Genetic Carrier Screening — Optional
This is performed for women before or during pregnancy to assess the risk of their children having genetic disorders such as:
- Spinal muscular atrophy (SMA): A disease that results in the death of nerve cells in the spinal cord leading to paralysis. Approximately 1 in 40-60 people carry this gene, and 1 in 6,000-10,000 babies are affected by this disorder.
- Cystic fibrosis (CF): A life-threatening disorder that affects the lungs and pancreas. This disease is most common in non-Hispanic white people, affecting 1 in 2,500 people in that population.
- Sickle Cell disorder: A disease that affects blood cell formation which results in anemia, pain, vascular issues, and multiple other serious health complications. Approximately 1 in 10 African Americans are carriers of sickle cell, and 1 in 300-500 African American newborns have sickle cell disease.
- Fragile X disorder: the most common cause of intellectual disability. This disorder occurs in 1 in 3,600 males and 1 in 4,000-6,000 females. Fragile X syndrome is a common cause of autism.
Screening for Chromosomal Disorders — Optional
This test detects an extra or missing chromosome or piece of chromosome in the fetus, which affects 1 in 150 births. Chromosomal disorders can affect any pregnancy but become more common as women age. Disorders such as Down Syndrome can be detected through several tests in this class that include:
- Cell-free DNA testing: A blood test performed any time after 10 weeks of pregnancy. Fetal DNA is detected in the mother’s blood. This test detects 98-99% of the most common chromosomal disorders and has the lowest false positive rate. This test also detects fetal sex.
- First-trimester screening: A combination of blood testing and ultrasound looking at the thickness of the fetal neck performed from 10-14 weeks. This testing detects 82-87% of cases of Down syndrome. An ultrasound abnormality at this stage can also indicate a possible cardiac defect.
- AFP (Alpha-fetoprotein) screening: Blood testing that is ideally performed from 15-18 weeks. This test identifies pregnancies at risk for neural tube defects (issues with the brain or spine such as spina bifida).
- Second trimester/Quad screening: A blood test performed from 15-22 weeks of pregnancy. This test detects 81% of cases of Down syndrome. This testing also includes AFP testing. First trimester and second-trimester testing can be combined for increased accuracy.
While the screening tests discussed above seek to identify pregnancies that are at risk for a genetic disorder, more genetic diagnostic tests can determine with as much certainty as possible if a genetic abnormality is present. These tests may be recommended if a screening test is positive, if an ultrasound abnormality is identified, or if there is a genetic disorder that runs in the family.
- Chorionic Villus Sampling: Testing performed from 10-13 weeks. A sample of placental cells is obtained through the cervix or the abdomen, and the DNA is analyzed.
- Amniocentesis: Testing performed from 15-20 weeks. While watching with ultrasound a needle is passed across the abdomen to obtain a sample of amniotic fluid. DNA is obtained from fetal cells in the amniotic fluid and is analyzed.
Ultrasounds — Recommended
Most people will have multiple ultrasounds during pregnancy. Ultrasounds start in the first trimester to confirm that the pregnancy is correctly located in the uterus, to ensure the pregnancy is viable, to identify the number of fetuses present, and to help to establish a due date. Patients may undergo additional ultrasounds if they experience pain or bleeding in the first trimester. Sometimes an ultrasound needs to be performed transvaginally for full assessment in the first trimester.
In the second trimester, a complete assessment of fetal anatomy is performed typically from 18-22 weeks through another ultrasound. Some patients with risk factors will have this ultrasound with a high-risk specialist (Maternal-Fetal Medicine). The anatomy ultrasound includes imaging of the fetal head and brain, neck, face, chest and heart, abdomen, spine, extremities, and genitals. The placenta is assessed for issues such as placenta previa, and the cervix is assessed to ensure it is not shortening or dilating prematurely.
An ultrasound is sometimes performed in the third trimester to assess the fetal size/growth and the amniotic fluid. Patients with health or pregnancy risk factors that can affect fetal growth are scheduled for these ultrasounds. Other patients may be scheduled for a growth ultrasound if the abdomen is measuring smaller or larger than expected.
Fetal Monitoring — Recommended for At-Risk Patients
Antenatal fetal monitoring is recommended for patients with medical conditions or pregnancy complications that put the pregnancy at increased risk for stillbirth. Examples include but are not limited to high blood pressure, diabetes, obesity, fetal growth problems, fetal anomalies, and multiples. The timing and frequency of testing vary based on condition, but most often testing starts at 32 weeks and occurs twice weekly.
Gestational Diabetes Screening — Recommended
Chemicals released by the placenta sometimes cause pregnant women to develop gestational diabetes—this is one of the most common complications during pregnancy. It is important to detect gestational diabetes because it increases the risk for adverse pregnancy outcomes including preeclampsia, need for c-section, stillbirth, large birth weight, shoulder dystocia, birth injury, and low blood sugar for the baby after birth. Screening is typically performed from 24-28 weeks, though for women with risk factors screening may be recommended earlier in pregnancy. Learn more about this process and what it means here.
Group B Strep Culture — Recommended
Group B strep (GBS; Streptococcus agalactiae) is a bacteria that colonizes the vagina or GI tract of approximately 10-30% of women. GBS is a leading cause of infections for newborn babies. If untreated, about half of women who are colonized with GBS will pass the bacteria to the infant during labor after the water is broken or while the infant passes through the birth canal. To prevent newborn illness, women are tested around 36 weeks for group B strep. Women who test positive for GBS should receive antibiotics during labor to lower the baby’s risk of getting an infection.
With this wealth of information, pregnant women can make informed decisions about their health that benefit both mother and child.
For more information about pregnancy care or to find an OB/GYN in the Atrium Health system, consult Atrium Health’s list of OB/GYN physicians or visit the Women’s Resource Hub.
To get vaccinated against COVID-19, schedule your appointment online today.
To get treatment for the flu or to schedule a flu shot appointment, get care now.
