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Medical Care During Pregnancy


Raul Artal-Mittelmark

, MD, Saint Louis University School of Medicine

Reviewed/Revised May 2021 | Modified Sep 2022
Topic Resources

Ideally, a couple who is thinking of having a baby should see a doctor or other health care practitioner to discuss whether pregnancy is advisable. Usually, pregnancy is very safe. However, some disorders can become severe during pregnancy. Also, for some couples, the risk of having a baby with a hereditary disorder is increased.

As soon as a couple is thinking of having a baby, the woman should start taking a multivitamin that contains folate Folate Deficiency Folate deficiency is common. Because the body stores only a small amount of folate, a diet lacking in folate leads to a deficiency within a few months. Not eating enough raw leafy vegetables... read more (folic acid) once a day. The lowest amount recommended for women of childbearing age is 400 micrograms, but some experts recommend taking slightly higher amounts, such as 600 or 800 micrograms. Such doses are often available in over-the-counter products, such as multivitamins. Folate reduces the risk of having a baby with a birth defect of the spinal cord or brain (neural tube defect Neural Tube Defects and Spina Bifida Neural tube defects are a certain type of birth defect of the brain, spine, and/or spinal cord. Neural tube defects can result in nerve damage, learning disabilities, paralysis, and death. The... read more ). Women who have had a baby with a neural tube defect should start taking a much larger amount than usually recommended: 4,000 micrograms as soon as they start thinking of having another baby. Doses of 1,000 micrograms or higher are available only with a prescription.

Did You Know...

  • Women who are thinking of becoming pregnant should start taking a multivitamin that contains folate (which helps prevent certain birth defects) rather than waiting until they are pregnant.

If the couple decides to try to have a baby, they and the doctor discuss ways to make the pregnancy as healthy as possible. The woman should ask the doctor about factors that could impair her health or the health of the developing fetus.

Factors or situations to avoid include the following:

Chickenpox and shingles are caused by herpes viruses. During delivery, these viruses can be spread to the fetus and cause severe illness. The virus can also cause pneumonia, which is occasionally severe, in the woman.

Knowing about and dealing with such factors before pregnancy may help reduce the risk of problems during pregnancy (see High-Risk Pregnancy Risk Factors for High-Risk Pregnancy Some risk factors are present before women become pregnant. These risk factors include Certain physical characteristics, such as age and weight Problems in a previous pregnancy, including the... read more Risk Factors for High-Risk Pregnancy ). In addition, the woman can discuss her diet and her social, emotional, and medical concerns with the doctor.

When a woman sees a doctor or another health care practitioner before she is pregnant, she can be given any needed vaccines, such as the rubella vaccine Measles, Mumps, and Rubella Vaccine The measles, mumps, and rubella (MMR) vaccine is a combination vaccine that helps protect against these three serious viral infections. The vaccine contains live but weakened measles, mumps... read more . If she is not already taking folate, doctors can prescribe prenatal multivitamins that contain the recommended daily amount (RDA) of folate or a larger amount of folate if the woman has had a baby with a neural tube defect. If needed, genetic screening Genetic Counseling and Genetic Testing Before Pregnancy Genetic disorders are caused by abnormalities in one or more genes or chromosomes. Some genetic disorders are hereditary and others are spontaneous. Hereditary genetic disorders are passed down... read more can be done to determine whether the woman and her partner are at increased risk of having a baby with a hereditary genetic disorder.

First examination

After pregnancy is confirmed, the woman should have a physical examination, preferably between 6 and 8 weeks of pregnancy. At this time, the length of the pregnancy can be estimated and the date of delivery can be predicted as accurately as possible.

The first physical examination during pregnancy is very thorough. It includes the following:

Other tests may be done, depending on the woman’s situation. Thyroid hormone levels may be measured in some women (such as those with who have had a thyroid disorder, diabetes, infertility, or miscarriage).

If the woman has Rh-negative blood, it is tested for antibodies to the Rh factor (see Rh Incompatibility Hemolytic Disease of the Fetus and Newborn Rh incompatibility occurs when a pregnant woman has Rh-negative blood and the fetus has Rh-positive blood. Rh incompatibility can result in destruction of the fetus’s red blood cells, sometimes... read more ). The woman's immune system produces these antibodies when her Rh-negative blood comes in contact with Rh-positive blood—for example, in a previous pregnancy with a fetus who has Rh-positive blood. The antibodies (called Rh antibodies) may destroy blood cells in a fetus with Rh-positive blood, causing severe problems (even death) for the fetus. If antibodies in a pregnant woman’s blood are detected early, the doctor can take measures to protect the fetus. All women with Rh-negative blood are given Rh(D) immune globulin, injected into a muscle, at 28 weeks of pregnancy. They are also given an injection after any possible contact between their blood and the fetus's blood—for example, after an episode of vaginal bleeding or amniocentesis and after delivery. Rh(D) immune globulin reduces the risk that the fetus's blood cells will be destroyed.

Did You Know...

  • Things to avoid during pregnancy include tobacco, second-hand smoke, drugs, alcohol, cat litter and feces, and contact with people who may have chickenpox or shingles.

  • During the flu season, all pregnant women should get a flu shot.

Follow-up examinations

After the first examination, a pregnant woman should see her doctor as follows:

  • Every 4 weeks until 28 weeks of pregnancy

  • Then every 2 weeks until 36 weeks

  • Then once a week until delivery

At each examination, the woman’s weight and blood pressure are usually recorded, and the size of the uterus is noted to determine whether the fetus is growing normally. The woman’s ankles are examined for swelling.

Doctors check the heartbeat of the fetus. It can usually be detected at about 10 to 11 weeks with a handheld Doppler ultrasound Doppler ultrasonography Ultrasonography is a type of medical imaging that uses high-frequency sound (ultrasound) waves to produce images of internal organs and other tissues. During an ultrasound, a device called a... read more Doppler ultrasonography device. Once a heartbeat has been detected, doctors check it at each visit to determine whether it is normal.

At each visit, urine is tested for sugar. Sugar in the urine may indicate diabetes. If the urine contains sugar, a blood test to check for diabetes is done as soon as possible. Even if the urine does not contain sugar, doctors usually test all women for the type of diabetes that develops during pregnancy (gestational diabetes Gestational diabetes For women who have diabetes before they become pregnant, the risks of complications during pregnancy depend on how long diabetes has been present and whether complications of diabetes, such... read more ). This blood test is done at 24 to 28 weeks. It measures the level of sugar (glucose) in the blood 1 hour after women drink a liquid that contains a certain amount of glucose—called a glucose tolerance test. If women have risk factors for gestational diabetes, this test is done early in the pregnancy, preferably before 12 weeks.

Risk factors for gestational diabetes include the following:

If results of the initial test are normal, these at-risk women are retested at 24 to 28 weeks.

Blood tests to check for thyroid disorders is done if women

  • Have symptoms of a thyroid disorder

  • Come from an area where moderate to severe iodine insufficiency occurs

  • Have relatives who have had a thyroid disorder

  • Have had a thyroid disorder

  • Have type 1 diabetes

  • Have had infertility problems, early delivery of a baby, or a miscarriage

  • Have had head or neck radiation therapy

  • Are severely obese

  • Are over 30 years old


Most doctors believe that ultrasonography Ultrasonography Ultrasonography is a type of medical imaging that uses high-frequency sound (ultrasound) waves to produce images of internal organs and other tissues. During an ultrasound, a device called a... read more Ultrasonography , the safest imaging procedure, should be done at least once during a pregnancy to make sure the fetus is normally formed and to verify the expected date of delivery. It is usually done between 16 and 20 weeks of pregnancy.

For the procedure, a device that produces sound waves (transducer) is placed on the woman’s abdomen. The sound waves are processed to form an image that is displayed on a monitor. Sometimes, particularly during early pregnancy, the doctor uses an ultrasound device that can be inserted in the vagina. Ultrasonography produces high-quality images, including live-action images that show the fetus in motion. These images provide the doctor with useful information and can reassure a pregnant woman.

Ultrasound Scanning in Pregnancy: Technique

Ultrasonography can also be used to do the following:

Toward the end of pregnancy, ultrasonography may be used to identify premature rupture of the fluid-filled membranes containing the fetus. Ultrasonography can provide information that helps doctors decide whether cesarean delivery is needed.


Other imaging

X-rays are not routinely taken during pregnancy, but they can be taken safely when necessary. If an x-ray is required, the fetus is shielded by placing a lead-filled garment over the woman’s lower abdomen to cover the uterus.


Experts recommend a booster shot for tetanus, diphtheria, and pertussis (Tdap Diphtheria-Tetanus-Pertussis Vaccine The diphtheria, tetanus, and pertussis vaccine is a combination vaccine that protects against these three diseases: Diphtheria usually causes inflammation of the throat and mucous membranes... read more ) after 20 weeks of pregnancy (preferably at 27 to 36 weeks) or after delivery, even if the shots are up-to-date.

Although the COVID-19 vaccine Treatment COVID-19 is an acute respiratory illness that can be severe and is caused by the coronavirus named SARS-CoV-2. Symptoms of COVID-19 vary significantly. Two types of tests can be used to diagnose... read more has not been specifically evaluated in pregnant women, experts recommend that the COVID-19 vaccine can be given to pregnant women who are eligible for vaccination and who have no contraindications to the vaccine, such as allergy to a component of the vaccine. No vaccines have been fully approved by the U.S. Food and Drug Administration (FDA), but some have been authorized for emergency use. (See also the Centers for Disease Control and Prevention: COVID-19 Vaccination.)

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