Is doxycycline (tetracycline antibiotic) safe during pregnancy?

From the Guidelines

Doxycycline should be avoided during pregnancy due to potential risks to the fetus, including cosmetic staining of primary dentition and possible effects on musculoskeletal development, as noted in the 2016 MMWR Recommendations and Reports 1.

Key Considerations

• The use of tetracycline-class drugs, including doxycycline, has been contraindicated during pregnancy because of concerns about potential risks to the fetus, such as cosmetic staining of primary dentition and effects on musculoskeletal development 1.
• Although controlled studies to assess the safety of doxycycline use in pregnant women have not been conducted, available data are primarily observational and suggest that therapeutic doses are unlikely to pose a substantial teratogenic risk 1.
• However, the data are insufficient to conclude that no risk exists, and the risk for cosmetic staining of the primary teeth by doxycycline could not be determined due to limited data 1.

Alternatives and Precautions

• If an antibiotic is needed during pregnancy, safer alternatives include penicillins (such as amoxicillin), cephalosporins, or azithromycin, which have established safety profiles in pregnancy.
• Women who discover they are pregnant while taking doxycycline should contact their healthcare provider immediately to discuss switching to a safer alternative.
• Women of childbearing age should use effective contraception while taking doxycycline and inform their doctor if pregnancy is planned or suspected.

Breastfeeding Considerations

• Doxycycline is excreted into breast milk at low levels, and short-term use is considered probably safe during lactation on the basis of available literature and expert opinion 1.

From the FDA Drug Label

Pregnancy: Teratogenic effects. Pregnancy Category D: There are no adequate and well-controlled studies on the use of doxycycline in pregnant women The vast majority of reported experience with doxycycline during human pregnancy is short-term, first trimester exposure. There are no human data available to assess the effects of long-term therapy of doxycycline in pregnant women, such as that proposed for treatment of anthrax exposure An expert review of published data on experiences with doxycycline use during pregnancy by TERIS – the Teratogen Information System – concluded that therapeutic doses during pregnancy are unlikely to pose a substantial teratogenic risk (the quantity and quality of data were assessed as limited to fair), but the data are insufficient to state that there is no risk

Doxycycline use in pregnancy is associated with a potential risk of teratogenic effects, and it is classified as a Pregnancy Category D drug.

• The available data on the use of doxycycline in pregnant women are limited, and most of the reported experience is from short-term, first-trimester exposure.
• There is no conclusive evidence to determine the safety of doxycycline use during pregnancy, and the potential risks and benefits should be carefully considered before prescribing the drug to pregnant women 2.
• The decision to use doxycycline in pregnancy should be made with caution, taking into account the potential risks to the fetus and the importance of the drug to the mother.

From the Research

Doxycycline Use in Pregnancy

• Doxycycline is classified as a class D drug, which is contraindicated in pregnancy and in children under 8 years of age 3.
• However, studies have shown that doxycycline may be safe to use in pregnancy, with no correlation between its use and teratogenic effects or dental staining in children 3, 4.
• A systematic review of the available literature on doxycycline use in pregnant women and children revealed a safety profile that differed significantly from that of tetracycline 3.
• The teratogenic potential of doxycycline in humans is considered "unlikely" based on available data 5.
• A study using the United States Food and Drug Administration Adverse Event Reporting System database found that the number of reported adverse pregnancy or neonatal outcomes following doxycycline use is small, and there does not seem to be a strong signal of harm 6.

Adverse Pregnancy Outcomes

• Adverse event reports related to doxycycline use during pregnancy included premature delivery, spontaneous abortion, intrauterine death, and congenital anomalies 6.
• However, many of these reports also involved the use of other medications that could have contributed to the outcome, making it difficult to determine the role of doxycycline 6.
• A study found that treatment with doxycycline during pregnancy presents very little if any teratogenic risk to the fetus 4.

Comparison with Other Antibiotics

• Doxycycline is considered compatible with breastfeeding, unlike some other antibiotics such as chloramphenicol 5.
• The cost of doxycycline is substantially lower than that of some other antibiotics, such as azithromycin and clarithromycin 7.