Pregnant Travelers

CDC Yellow Book 2024

Family Travel

Author(s): Romeo Galang, I. Dale Carroll, Titilope Oduyebo

Pregnancy can cause physiologic changes that require special consideration during travel. With careful preparation, however, most pregnant people can travel safely.

Pretravel Consultation

The pretravel consultation and evaluation of pregnant travelers (Box 7-01) should begin with a careful medical and obstetric history, specifically assessing gestational age and the presence of factors and conditions that increase risk for adverse pregnancy outcomes. A visit with an obstetric health care provider also should be a part of the pretravel assessment to ensure routine prenatal care and identify any potential problems. Instruct pregnant travelers to carry with them a copy of their prenatal records and physician’s contact information.

Review the pregnant person’s travel itinerary, including accommodations, activities, and destinations, to guide pretravel health advice. Discourage pregnant travelers from undertaking unaccustomed vigorous activity. Swimming and snorkeling during pregnancy generally are safe, but falls during waterskiing have been reported to inject water into the birth canal. Most experts advise against scuba diving for pregnant people because of risk for fetal gas embolism during decompression (see Sec. 4, Ch. 4, Scuba Diving: Decompression Illness & Other Dive-Related Injuries). Riding animals, bicycles, or motorcycles presents risks for abdominal trauma.

Educate pregnant people on how to avoid travel-associated risks, manage minor pregnancy discomforts, and recognize more serious complications. Advise pregnant people to seek urgent medical attention if they experience contractions or premature labor; symptoms of deep vein thrombosis (e.g., unusual leg swelling and pain in the calf or thigh) or pulmonary embolism (e.g., unusual shortness of breath); dehydration, diarrhea, or vomiting; severe pelvic or abdominal pain; symptoms of preeclampsia (e.g., severe headaches, nausea and vomiting, unusual swelling, vision changes); prelabor rupture of the membranes; or vaginal bleeding.

Box 7-01 Pretravel consultation for pregnant travelers: a checklist for health care providers

☐ Review vaccination history (e.g., COVID-19, hepatitis A, hepatitis B, measles, pertussis, rubella, varicella, tetanus) and update vaccinations as needed (see text for contraindications during pregnancy)

☐ Policies and paperwork

  • Discuss supplemental travel insurance, travel health insurance, and medical evacuation insurance; research specific coverage information and limitations for pregnancy-related health issues
  • Advise travelers to check airline and cruise line policies for pregnant travelers
  • Provide letter confirming due date and fitness to travel
  • Provide copy of medical records

☐ Prepare for obstetric care at destination

  • Advise traveler to arrange for obstetric care at destination, as needed

☐ Review signs and symptoms requiring immediate care, including

  • Bleeding
  • Contractions or preterm labor
  • Deep vein thrombosis or pulmonary embolism symptoms, which include unusual swelling of leg with pain in calf or thigh, unusual shortness of breath
  • Pelvic or abdominal pain
  • Preeclampsia symptoms (e.g., unusual swelling, severe headaches, nausea and vomiting, vision changes)
  • Rupture of membranes
  • Vomiting, diarrhea, dehydration

Contraindications to Travel During Pregnancy

Absolute contraindications are conditions for which the potential harm of travel during pregnancy always outweighs the benefits of travel to the pregnant person or fetus. Relative contraindications are conditions for which travel should be avoided if the potential harm from travel outweighs its benefits (Box 7-02).

Although travel is rarely contraindicated during a normal pregnancy, pregnancies that require frequent antenatal monitoring or close medical supervision might warrant a recommendation that travel be delayed. Educate pregnant travelers that the risk of obstetric complications is greatest in the first and third trimesters of pregnancy.

Box 7-02 Contraindications to travel during pregnancy

ABSOLUTE CONTRAINDICATIONS

  • Abruptio placentae
  • Active labor
  • Incompetent cervix
  • Premature labor
  • Premature rupture of membranes
  • Suspected ectopic pregnancy
  • Threatened abortion / vaginal bleeding
  • Toxemia, past or present

RELATIVE CONTRAINDICATIONS

  • Abnormal presentation
  • Fetal growth restriction
  • History of infertility
  • History of miscarriage or ectopic pregnancy
  • Maternal age <15 or >35 years
  • Multiple gestation
  • Placenta previa or other placental abnormality

Planning for Emergency Care

Obstetric emergencies are often sudden and life-threatening. Advise all pregnant travelers (but especially those in their third trimester or otherwise at high risk) to identify, in advance, international medical facilities at their destination(s) capable of managing complications of pregnancy, delivery (including by caesarean section), and neonatal problems. Counsel against travel to areas where obstetric care might be less than the standard at home.

Many health insurance policies do not cover the cost of medical treatment for pregnancy or neonatal complications that occur overseas. Pregnant people should strongly consider purchasing supplemental travel health insurance to cover pregnancy-related problems and care of the neonate, as needed. In addition, pregnant travelers should consider medical evacuation insurance coverage in case of pregnancy-related complications (see Sec. 6, Ch. 1, Travel Insurance, Travel Health Insurance & Medical Evacuation Insurance).

Medications

Over-the-counter drugs and nondrug remedies can help a pregnant person travel more comfortably. For instance, pregnant people can safely use a mild bulk laxative for constipation. In addition, several simple available remedies are effective in relieving the symptoms of morning sickness. Nonprescription remedies include ginger, available as a powder that can be mixed with food or drinks (e.g., tea), and as candy (e.g., lollipops). Similarly, pyridoxine (vitamin B6) is effective in reducing symptoms of morning sickness and is available in tablet form, as well as lozenges and lollipops. Antihistamines (e.g., dimenhydrinate, meclizine) often are used in pregnancy for morning sickness and motion sickness and appear to have a good safety record.

Carefully consider appropriate pain management and use of analgesics during pregnancy. Acetaminophen remains the nonopioid analgesic of choice during pregnancy. Although low-dose aspirin has been demonstrated to be relatively safe during pregnancy for certain clinical indications, it should be used cautiously. Aspirin can increase the incidence of abruption, and other anti-inflammatory agents can cause premature closure of the ductus arteriosus.

Various systems are used to classify drugs with respect to their safety in pregnancy. Refer to specific data about the effects of a given drug during pregnancy rather than depending on a classification. Counsel patients to help them make a balanced decision on the use of medications during pregnancy.

Vaccinations

In the best possible scenario, people should be up to date on routine vaccinations before becoming pregnant. The most effective way of protecting the infant against many diseases is to vaccinate the pregnant person. See a summary of current Advisory Committee on Immunization Practices (ACIP) guidelines for vaccinating pregnant people.

Coronavirus Disease 2019

Pregnant people are more likely to become more severely ill from coronavirus disease 2019 (COVID-19) than people who are not pregnant. Having COVID-19 during pregnancy increases a person’s risk of complications that can affect their pregnancy. For these reasons, the Centers for Disease Control and Prevention (CDC) recommends that people who are pregnant, trying to get pregnant, or who might become pregnant in the future get vaccinated against COVID-19. As of August 2022, the COVID-19 vaccines authorized or approved for use in the United States are nonreplicating vaccines that do not cause infection in the pregnant person or the fetus. Pregnant people may choose to receive any of the COVID-19 vaccines authorized or approved for use in the United States; the ACIP does not state a preference.

COVID-19 vaccination can be safely provided before pregnancy or during any trimester of pregnancy. Available vaccines are highly effective in preventing severe COVID-19, hospitalizations, and deaths; data have shown that the benefits of vaccination during pregnancy, to both the pregnant person and their fetus, outweigh any potential risks. Pregnant people might want to speak with their health care provider before making a decision about receiving COVID-19 vaccine, but a consultation is not required before vaccination. Side effects from COVID-19 vaccination in pregnant people are like those expected among nonpregnant people. Pregnant people can take acetaminophen if they experience fever or other post-vaccination symptoms.

Influenza

The ACIP recommends that all people who are or who will become pregnant during the influenza season have an annual influenza vaccine using inactivated virus. Influenza vaccines can be administered during any trimester.

Hepatitis

The safety of hepatitis A vaccination during pregnancy has not been determined; because hepatitis A vaccine is produced from inactivated virus, though, the risk to the developing fetus is expected to be low. Weigh the risk associated with vaccination against the risk for infection in pregnant people who could be at increased risk for exposure to hepatitis A virus. According to the ACIP, pregnant people traveling internationally are at risk of hepatitis A virus infection; ACIP recommends vaccination during pregnancy for nonimmune international travelers.

Limited data suggest that developing fetuses are not at risk for adverse events resulting from vaccination of pregnant people with hepatitis B vaccine (for details, see Sec. 5, Part 2, Ch. 8, Hepatitis B). ACIP recommends vaccinating pregnant people identified as being at risk for hepatitis B virus infection during pregnancy; risk factors include >1 sex partner during the previous 6 months, being evaluated or treated for a sexually transmitted infection, recent or current injection drug use, or having a HBsAg-positive sex partner. In November 2021, ACIP recommended vaccination of all adults 19–59 years old.

Japanese Encephalitis

Data are insufficient to make specific recommendations for use of Japanese encephalitis vaccine in pregnant people (see Sec. 5, Part 2, Ch. 13, Japanese Encephalitis).

Live-Virus Vaccines

Most live-virus vaccines, including live attenuated influenza, measles-mumps-rubella, live typhoid (Ty21a), and varicella, are contraindicated during pregnancy. Postexposure prophylaxis of a nonimmune pregnant person exposed to measles can be provided by administering measles immune globulin (IG) within 6 days of exposure; for varicella exposures, varicella-zoster IG can be given within 10 days. Advise people planning to become pregnant to wait ≥4 weeks after receiving a live-virus vaccine before conceiving.

Yellow Fever

Yellow fever vaccine is the exception to the rule about live-virus vaccines being contraindicated during pregnancy. ACIP considers pregnancy a precaution (i.e., a relative contraindication) for yellow fever vaccine. If travel is unavoidable, and the risk for yellow fever virus exposure outweighs the vaccination risk, it is appropriate to recommend vaccination. If the risks for vaccination outweigh the risks for yellow fever virus exposure, consider providing a medical waiver to the pregnant traveler to fulfill health regulations. Because pregnancy might affect immune responses to vaccination, consider performing serologic testing to document an immune response to yellow fever vaccine. Furthermore, if a person was pregnant (regardless of trimester) when they received their initial dose of yellow fever vaccine, they should receive 1 additional dose before they are next at risk for yellow fever virus exposure (see Sec. 5, Part 2, Ch. 26, Yellow Fever).

Meningococcal

According to the ACIP, pregnant (and lactating) people should receive quadrivalent meningococcal vaccine, if indicated. Meningococcal vaccine might be indicated for international travelers, depending on risk for infection at the destination (see Sec. 5, Part 1, Ch. 13, Meningococcal Disease).

Polio

No adverse events linked to inactivated polio vaccine (IPV) have been documented among pregnant people or their fetuses. Vaccination of pregnant people should be avoided, however, because of theoretical concerns. IPV can be administered in accordance with the recommended immunization schedule for adults if a pregnant person is at increased risk for infection and requires immediate protection against polio (see Sec. 5, Part 2, Ch. 17, Poliomyelitis).

Rabies

Administer rabies postexposure prophylaxis with rabies immune globulin and vaccine after any moderate- or high-risk exposure to rabies; consider preexposure vaccine for travelers who have a substantial risk for exposure (see Sec. 5, Part 2, Ch. 18, Rabies).

Tetanus-Diphtheria-Pertussis

Tetanus, diphtheria, and acellular pertussis vaccine (Tdap) should be given during each pregnancy irrespective of a person’s history of receiving the vaccine previously. To maximize maternal antibody response and passive antibody transfer to the infant, optimal timing for Tdap administration is between 27 and 36 weeks’ gestation (earlier during this time frame is preferred), but it may be given at any time during pregnancy.

Malaria Prophylaxis

Malaria, caused by Plasmodium spp. parasites transmitted by mosquitoes, can be much more serious in pregnant than in nonpregnant people and is associated with high risks of illness and death for both mother and fetus. Malaria in pregnancy can be characterized by heavy parasitemia, severe anemia, and profound hypoglycemia, and can be complicated by cerebral malaria and acute respiratory distress syndrome. Placental sequestration of parasites might result in fetal loss due to abruption, premature labor, or miscarriage. An infant born to an infected mother is apt to be of low birth weight, and, although rare, congenital malaria is possible.

Because no prophylactic regimen provides complete protection, pregnant people should avoid or delay travel to malaria-endemic areas. If travel is unavoidable, the pregnant person should take precautions to avoid mosquito bites and use an effective prophylactic regimen.

Chloroquine is the drug of choice for pregnant travelers going to destinations with chloroquine-sensitive Plasmodium spp., and mefloquine is the drug of choice for pregnant travelers going to destinations with chloroquine-resistant Plasmodium spp. Doxycycline is contraindicated because of teratogenic effects on the fetus after the fourth month of pregnancy. Primaquine is contraindicated in pregnancy because the infant cannot be tested for glucose-6-phosphate dehydrogenase deficiency, putting the infant at risk for hemolytic anemia. Atovaquone-proguanil is not recommended because of lack of available safety data. A list of the available antimalarial drugs and their uses and contraindications during pregnancy can be found in Sec. 5, Part 3, Ch. 16, Malaria.

Travel Health Kits

In addition to the recommended travel health kit items for all travelers (see Sec. 2, Ch. 10, Travel Health Kits), pregnant travelers should pack antacids, antiemetic drugs, graduated compression stockings, hemorrhoid cream, medication for vaginitis or yeast infection, prenatal vitamins, and prescription medications. Encourage pregnant travelers to consider packing a blood pressure monitor if travel will limit access to a health center where blood pressure monitoring is available.

Infectious Disease Concerns

Respiratory and urinary infections and vaginitis are more likely to occur and to be more severe during pregnancy. Pregnant people who develop travelers’ diarrhea or other gastrointestinal infections might be more vulnerable to dehydration than nonpregnant travelers. Stress the need for strict hand hygiene and food and water precautions (see Sec. 2, Ch. 8, Food & Water Precautions). Drinking bottled or boiled water is preferable to chemically treated or filtered water. Pregnant people should not consume water purified by iodine-containing compounds because of potential effects on the fetal thyroid (see Sec. 2, Ch. 9, Water Disinfection).

Coronavirus Disease 2019

As mentioned previously, pregnant people are at increased risk for severe COVID-19–associated illness (e.g., requiring invasive ventilation or extracorporeal membrane oxygenation) and death compared with people who are not pregnant. Underlying medical conditions (e.g., chronic kidney disease, diabetes, obesity) and other factors (e.g., age, occupation) can further increase a pregnant person’s risk for developing severe illness. Additionally, pregnant people with COVID-19 are at greater risk for preterm birth and other adverse outcomes.

Pregnant people, recently pregnant people, and those who live with or visit them should take steps to protect themselves from getting COVID-19. CDC recommends that people (including those who are pregnant) not travel internationally until they are up to date with their COVID-19 vaccines. Additional information for international travelers is available at CDC's International Travel website.

Hepatitis

Hepatitis A and hepatitis E are both spread by the fecal–oral route (see Sec. 5, Part 2, Ch. 7, Hepatitis A, and Sec. 5, Part 2, Ch. 10, Hepatitis E). Hepatitis A has been reported to increase the risk for placental abruption and premature delivery. Hepatitis E is more likely to cause severe disease during pregnancy and could result in a case-fatality rate of 15%–30%; when acquired during the third trimester, hepatitis E is also associated with fetal complications and fetal death.

Listeriosis & Toxoplasmosis

Listeriosis and toxoplasmosis (see Sec. 5, Part 3, Ch. 23, Toxoplasmosis) are foodborne illnesses of particular concern during pregnancy because the infection can cross the placenta and cause spontaneous abortion, stillbirth, or congenital or neonatal infection. Warn pregnant travelers to avoid unpasteurized cheeses and uncooked or undercooked meat products. Risk for fetal infection increases with gestational age, but severity of infection is decreased.

Other Parasitic Infections & Diseases

Parasitic infections and diseases can be a concern, particularly for pregnant people visiting friends and relatives in low- and middle-income countries. In general, intestinal helminths rarely cause enough illness to warrant treatment during pregnancy. Most, in fact, can be addressed safely with symptomatic treatment until the pregnancy is over. On the other hand, protozoan intestinal infections (e.g., Cryptosporidium, Entamoeba histolytica, Giardia) often do require treatment. These parasites can cause acute gastroenteritis, severe dehydration, and chronic malabsorption resulting in fetal growth restriction. E. histolytica can cause invasive disease, including amebic liver abscess and colitis. Pregnant people also should avoid bathing, swimming, or wading in freshwater lakes, rivers, and streams that can harbor the parasitic worms (schistosomes) that cause schistosomiasis (see Sec. 5, Part 3, Ch. 20, Schistosomiasis).

Travelers’ Diarrhea

The treatment of choice for travelers’ diarrhea is prompt and vigorous oral hydration; azithromycin or a third-generation cephalosporin may, however, be given to pregnant people if clinically indicated. Avoid use of bismuth subsalicylate because of the potential impact of salicylates on the fetus. In addition, fluoroquinolones are contraindicated in pregnancy due to toxicity to developing cartilage, as noted in experimental animal studies.

Vectorborne Infections

Pregnant people should avoid mosquito bites when traveling in areas where vectorborne diseases are endemic. Preventive measures include use of Environmental Protection Agency–registered insect repellants, protective clothing, and mosquito nets (see Sec. 4, Ch. 6, Mosquitoes, Ticks & Other Arthropods). For details on yellow fever vaccine and malaria prophylaxis during pregnancy, see above.

Zika

Zika virus is spread primarily through the bite of an infected Aedes mosquito (Ae. aegypti and Ae. albopictus) but can also be sexually transmitted. The illness associated with Zika can be asymptomatic or mild; some patients report acute onset of conjunctivitis, fever, joint pain, and rash that last for several days to a week after infection.

Birth defects caused by Zika virus infection during pregnancy include brain, eye, and neurodevelopmental abnormalities. Because of the risk for birth defects, CDC recommends pregnant people avoid travel to areas with a Zika outbreak, and, for the duration of the pregnancy, to avoid sex or use condoms with anyone who has traveled to a risk area.

Advise pregnant people considering travel to areas with Zika to carefully assess the risks of Zika infection during pregnancy; provide information about prevention strategies, signs and symptoms, and the limitations of Zika testing. Pregnant people should strictly follow steps to prevent mosquito bites and sexual transmission. See additional information, including the most current list of countries and territories where Zika is active. Guidance for pregnant people can be found on the CDC Zika website.

Environmental Health Concerns

Pregnant people should be aware of specific current environmental issues in their international destinations (e.g., natural disasters, special events or gatherings, travel warnings). More information can be found at the CDC Travelers’ Health website and on the destination pages of the US Department of State website.

Air Quality

Air pollution causes more health problems during pregnancy because ciliary clearance of the bronchial tree is slowed, and mucus is more abundant. For more details on traveling to destinations where air quality is poor, see Sec. 4, Ch. 3, Air Quality & Ionizing Radiation.

Extremes of Temperature

Body temperature regulation is not as efficient during pregnancy, and temperature extremes can create more physiological stress on the pregnant person (see Sec. 4, Ch. 2, Extremes of Temperature). In addition, increases in core temperature (e.g., heat exhaustion, heat stroke), might harm the fetus. The vasodilatory effect of a hot environment and dehydration might cause fainting. For these reasons, then, encourage pregnant travelers to seek air-conditioned accommodations and restrict their level of activity in hot environments. If heat exposure is unavoidable, the duration should be as short as possible to prevent an increase in core body temperature. Pregnant travelers should take measures to avoid dehydration and hyperthermia.

High Elevation Travel

Pregnant people should avoid activities at high elevation unless they have trained for and are accustomed to such activities; those not acclimated to high elevation might experience breathlessness and palpitations. The common symptoms of acute mountain sickness (insomnia, headache, and nausea) frequently are associated with pregnancy, and it might be difficult to distinguish the cause of the symptoms. Most experts recommend a slower ascent with adequate time for acclimatization. No studies or case reports show harm to a fetus if the mother travels briefly to high elevations during pregnancy; recommend that pregnant people not sleep at elevations >12,000 ft (≈3,600 m) above sea level, if possible. Probably the greatest concern is that high-elevation destinations often are inaccessible and far from medical care (see Sec. 4, Ch. 5, High Elevation Travel & Altitude Illness).

Transportation Considerations

Advise pregnant people to follow safety instructions for all forms of transport and to wear seat belts, when available, on all forms of transportation, including airplanes, buses, and cars (see Sec. 8, Ch. 5, Road & Traffic Safety). A diagonal shoulder strap with a lap belt provides the best protection. The shoulder belt should be worn between the breasts with the lap belt low across the upper thighs. When only a lap belt is available, pregnant people should wear it low, between the abdomen and across the upper thighs, not above or across the abdomen.

Air Travel

Most commercial airlines allow pregnant travelers to fly until 36 weeks’ gestation. Some limit international travel earlier in pregnancy, and some require documentation of gestational age. Pregnant travelers should check with the airline for specific requirements or guidance, and should consider the gestational age of the fetus on the dates both of departure and of return.

Most commercial jetliner cabins are pressurized to an equivalent outside air pressure of 6,000–8,000 ft (≈1,800–2,500 m) above sea level; travelers might also experience air pressures in this range during travel by hot air balloon or on noncommercial aircraft. The lower oxygen tension under these conditions likely will not cause fetal problems in a normal pregnancy. People with pregnancies complicated by conditions exacerbated by hypoxia (e.g., preexisting cardiovascular problems, sickle cell disease, severe anemia [hemoglobin <8.0 g/dL], intrauterine fetal growth restriction) could, however, experience adverse effects associated with low arterial oxygen saturation.

Risks of air travel include potential exposure to communicable diseases, immobility, and the common discomforts of flying. Abdominal distention and pedal edema frequently occur. The pregnant traveler might benefit from an upgrade in airline seating and should seek convenient and practical accommodations (e.g., proximity to the lavatory). Pregnant travelers should select aisle seating when possible, and wear loose fitting clothing and comfortable shoes that enable them to move about more easily and frequently during flights.

Some experts report that the risk for deep vein thrombosis (DVT) is 5–10 times greater among pregnant than nonpregnant people, although the absolute risk is low. To help prevent DVT, pregnant travelers should stay hydrated, stretch frequently, walk and perform isometric leg exercises, and wear graduated compression stockings (see Sec. 8, Ch. 3, Deep Vein Thrombosis & Pulmonary Embolism).

Cosmic radiation during air travel poses little threat to the fetus but might be a consideration for pregnant travelers who fly frequently (see Sec. 9, Ch. 3, . . . perspectives: People Who Fly for a Living—Health Myths & Realities). Older airport security machines are magnetometers and are not harmful to the fetus. Newer security machines use backscatter x-ray scanners, which emit low levels of radiation. Most experts agree that the risk for complications from radiation exposure from these scanners is extremely low.

Cruise Ship Travel

Most cruise lines restrict travel beyond 24 weeks’ gestation (see Sec. 8, Ch. 6, Cruise Ship Travel). Cruise lines might require pregnant travelers to carry a physician’s note stating that they are fit to travel, including the estimated date of delivery. Pregnant people should check with the cruise line for specific requirements or guidance. For pregnant travelers planning a cruise, provide advice about gastrointestinal and respiratory infections, motion sickness (see Sec. 8, Ch. 7, Motion Sickness), and the risk for falls on a moving vessel, as well as the possibility of delayed care while at sea.

The following authors contributed to the previous version of this chapter: Diane F. Morof, I. Dale Carroll

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