The information provided below is for readers based in the United States of America. Readers outside of the United States of America should seek the information from local sources.

What is pneumonia?

Pneumonia is an infection in the lungs, specifically in the alveoli (air sacs) deep within the lungs, which become inflamed and can fill with mucus or pus. This interferes with the exchange of the gases oxygen (O2) and carbon dioxide (CO2) between the blood and air. Usually, the infection is concentrated in one particular section of a lung, called a lobe (lobar pneumonia), so blood is still replenished with air from healthier lobes and from the other lung, but if very severe, the condition can cause low O2 saturation of the hemoglobin in your red blood cells (low O2 sat), making you very tired and ill. It also can cause your body to retain CO2, which causes the pH of your blood to decrease (the body becomes more acidic). Pneumonia also can occur as whats called bronchial pneumonia in which the infection is spread through multiple lobes, which is generally worse than having pneumonia more concentrated but limited to a single lobe. Along with disrupting gas exchange, pneumonia also produces chills and fever, which can be very high, particularly if the pneumonia is bacterial, plus it produces symptoms specific to the lungs, such as coughing, difficulty breathing, and chest pain.

The infection that causes pneumonia can be bacterial, viral, or fungal. About 75 percent of pneumonia cases are bacterial, and most of the rest is viral, due to the influenza virus. The most common bacterial species causing bacterial pneumonia is Streptococcus pneumoniae, also called pneumococcus, and there are several strains of this organism that cause human disease. Bacterial pneumonia also is frequently caused by Haemophilus influenzae, Staphylococcus aureus, and other species, including Clamydia pneumonia, Mycoplasma pneumoniae, and a group of bacteria called Legionella.

In addition to the causative organism and whether the pneumonia is concentrated in a lobe or dispersed, pneumonia also can be classified based on where it was acquired. In the case of pregnancy, generally, we are talking about community-acquired pneumonia, which is pneumonia that develops from an infectious agent that circulates through your normal environment. This contrasts with hospital-acquired pneumonia and ventilator-acquired pneumonia.

How common is pneumonia during pregnancy?

As noted above, most pneumonia is bacterial, and most bacterial pneumonia is caused by S. pneumoniae. This organism exists as multiple strains but overall produces pneumonia in approximately 1 million people in the US annually. Since pregnancy can often weaken the immune system, its quite possible for pneumococcal pneumonia, as well as viral pneumonia (usually from the flu) and other types of pneumonia to coincide with pregnancy. Most cases of pneumonia in pregnancy are community-acquired and caused by S. pneumoniae, H. influenzae, or M. pneumonia.

How is pneumonia diagnosed?

Suspicion of pneumonia will be high if you have symptoms of general illness such as fever, chills, lack of appetite, and fatigue, plus respiratory symptoms, including difficulty breathing, or shortness of breath. Although shortness of breath is common during pregnancy without a respiratory infection, rapid breathing (especially a breathing rate over 30 breaths per minute) is an important sign that you should be investigated further for the possibility of a respiratory infection. If you have lobar pneumonia, the doctor may be able to hear what are called crackles, when auscultating with a stethoscope over the affected area of the affected lung.

When the history and physical exam suggests possible pneumonia, your doctor will order imaging of the lungs. Usually, plain radiography X-ray imaging of the lungs from a couple of different angles is adequate, but in some cases computed tomography (CT) scanning can be useful. For pregnancy, plain radiography is much preferred, because it exposes the developing baby to very minimal radiation compared with CT. For an otherwise healthy woman, the main scenario that doctors are looking for is lobar pneumonia, which plain radiography will reveal as an area that reduces transmission of X-rays (looks whiter on the image that doctors see). However, your doctor also will order blood and urine tests to obtain various basic data on your blood cells and fluid and electrolyte balances, plus you will need to provide sputum that can be tested to identify the organism(s) causing the pneumonia, as knowing this will affect the treatment.

Does pneumonia cause problems during pregnancy?

Any case of pneumonia can become life-threatening, although there is a range of severity. Some patients can be treated outside the hospital and recover at home; sometimes, this is called ambulatory, or walking pneumonia. At the other end of the spectrum are cases of pneumonia that require admission into the intensive care unit (ICU). In between are a range of people who require hospital admission, but not necessarily into the ICU; instead, they can be monitored and treated in intermediate care, or in the regular internal medicine wards. If you are far along in your pregnancy and develop pneumonia, you could be admitted into obstetric care for monitoring and care, even if you are not yet ready to give birth.

Women with pneumonia can become dehydrated, which can make you feel horrible, along with putting various organ systems at risk. Your electrolytes and body pH can be thrown off, plus the fever can produce damage. Kidney function can be affected, as can the rhythm of the beating of the hearts upper chambers, called atria. Interference with the exchange of O2 and CO2 between air and blood can lead to O2-low saturation in your blood and tissues, threatening health and life. In addition to causing pneumonia, S. pneumoniae can work itself through your body, giving you sepsis (infection throughout the body), which also threatens life.

Does pneumonia during pregnancy cause problems for the baby?

Pneumonia in the mother can lead to low birth weight and elevate the risk of premature birth.

What to consider about taking medications when you are pregnant:

  • The risks to yourself and your baby if you do not treat the pneumonia
  • The risks and benefits of each medication you use when you are pregnant
  • The risks and benefits of each medication you use when you are breastfeeding

What should I know about using medication to treat pneumonia during pregnancy?

The basic strategy for managing community-acquired pneumonia is for doctors to start treatment with medications selected from two groups of antibiotics. One group of drugs, called beta-lactam antibiotics (the group that includes penicillins and cephalosporins), works well against certain common causative organisms such as S. pneumoniae, while the other group, called macrolide antibiotics, works well against Mycoplasma organisms, such as M. pneumonia, and also against another type of bacteria called Chlamydia that can also cause pneumonia. Also, there is a drug called clindamycin that is similar to macrolides. Several drugs from the beta-lactam group and some from the macrolide group and clindamycin are thought to be fairly safe during pregnancy, both for the mother and developing baby. Once the identity of the causative organism, and its susceptibility to antibiotics are known, the antibiotics can be replaced if necessary. Otherwise, however, the testing serves to
reassure you and your doctor that the treatment has been correct, so you will be further on the road to recovery.

Who should NOT stop taking medication for pneumonia during pregnancy?

Pneumonia is a life-threatening condition that can be cured with antibiotics, so you must follow the antibiotic regimen that is prescribed for you.

What should I know about choosing a medication for my pneumonia during pregnancy?

You may find Pregistrys expert reports about the individual medications to treat pneumonia here. Additional information can also be found in the sources listed at the end of this report.

What should I know about taking a medication for my pneumonia when I am breastfeeding?

There are many different antibiotic drugs. Some are a concern during breastfeeding while others are not, depending on whether they have been found to enter breastmilk, and if so whether they enter breastmilk in significant quantities to do harm. Bacterial pneumonia is a life-threatening infection. Thus, avoiding antibiotics is not an option, but particular drugs can be selected with minimal passage into breastmilk.

What alternative therapies besides medications can I use to treat my pneumonia during pregnancy?

There are no alternatives to antibiotics for bacterial pneumonia. However, vaccines are available that can reduce your risk of getting pneumonia in the first place. A pneumococcal vaccine is available, as is a vaccine against H. influenza type B (Hib). Generally, these two vaccines are not offered to adults of childbearing age who do not have particular health problems, but if your work puts you at risk for an infection with either organism, you should speak with your doctor to determine whether there is a way to get you immunized. In addition to protecting you against S. pneumoniae, the pneumococcal vaccine given to you may protect your newborn for up to 12 months after birth.

What can I do for myself and my baby when I have pneumonia during pregnancy?

Follow your doctors recommendations, including sticking precisely to your prescribed course of antibiotics.

Resources for pneumonia in pregnancy:

For more information about pneumonia during and after pregnancy, contact (800-994-9662 [TDD: 888-220-5446]) or read the following articles:


Read the whole report
General information

It is very common for women to worry about having a miscarriage or giving birth to a child with a birth defect while they are pregnant. Many decisions that women make about their health during pregnancy are made with these concerns in mind.

For many women these concerns are very real. As many as 1 in 5 pregnancies end in a miscarriage, and 1 in 33 babies are born with a birth defect. These rates are considered the background population risk, which means they do not take into consideration anything about the health of the mom, the medications she is taking, or the family history of the mom or the baby’s dad. A number of different things can increase these risks, including taking certain medications during pregnancy.

It is known that most medications, including over-the-counter medications, taken during pregnancy do get passed on to the baby. Fortunately, most medicines are not harmful to the baby and can be safely taken during pregnancy. But there are some that are known to be harmful to a baby’s normal development and growth, especially when they are taken during certain times of the pregnancy. Because of this, it is important to talk with your doctor or midwife about any medications you are taking, ideally before you even try to get pregnant.

If a doctor other than the one caring for your pregnancy recommends that you start a new medicine while you are pregnant, it is important that you let them know you are pregnant.

If you do need to take a new medication while pregnant, it is important to discuss the possible risks the medicine may pose on your pregnancy with your doctor or midwife. They can help you understand the benefits and the risks of taking the medicine.

Ultimately, the decision to start, stop, or change medications during pregnancy is up to you to make, along with input from your doctor or midwife. If you do take medications during pregnancy, be sure to keep track of all the medications you are taking.

Read articles about Pneumonia