Syphilis Is Still a Problem in Pregnancy

Note: The Pregistry website includes expert reports on more than 2000 medications, 300 diseases, and 150 common exposures during pregnancy and lactation. For the topic Syphilis, go here. These expert reports are free of charge and can be saved and shared.

COVID-19, the opioid crisis, delivery and cost of healthcare— despite these and other issues constituting challenges to medicine, an old disease still presents itself in some cases of pregnancy and that old disease is syphilis. This is a sexually transmitted disease (STD) as well as a congenitally transmitted disease, meaning passed from mother to newborn. According to the US Centers for Disease Control and Prevention (CDC), the years 2010 through 2018 saw the number of cases of syphilis in women ages 15 to 44 more than quadruple, while cases of congenital syphilis (syphilis in the newborn) more than tripled during the same period. African Americans in particular suffer from this disease, incurring syphilis rates more than five times the rates in Caucasians.

Syphilis results from infection by a bacterial species called Treponema pallidum, which belongs to a group of bacteria called Spirochaetes. These bacteria have a distinct corkscrew or spiral shape and also have a double-membrane surrounding them. Syphilis develops in a series of classic stages. The first stage, called primary syphilis, develops around three weeks after contact. This stage presents with a sore called a chancre on skin at the location where the T. pallidum penetrated into the body after sexual contact. Two to eight weeks after the chancre heals, secondary syphilis begins as the spread of the bacteria through the blood causes symptoms throughout the body, especially the nervous system. This second stage also is called neurosyphilis but also can include dysfunction of the kidneys. It can be followed by a latent period, a period during which the person does not experience symptoms, but can have occasional relapses.

There is a late phase of the latent period (sometimes called late latent syphilis) that is important in connection with pregnancy, because it is a time when syphilis can be transmitted to a fetus. The final stage of the disease, called tertiary syphilis, that can develop 1 – 20 years after the initial infection. This phase can involve more problems in the nervous system, so it is also called late neurosyphilis. The problems can include meningitis (inflammation of the protective layers covering the brain) and abnormalities in the blood vessels of those protective layers. Tertiary syphilis also may include cardiovascular syphilis. This may include problems with the aortic valve, the valve between the heart’s left ventricle and the large artery called the aorta. It may also include aneurysm (ballooning out) of the aorta and narrowing of the openings in to the coronary arteries.

Doctors will have a strong suspicion that you may have primary or secondary syphilis, based on a history that includes either a high number of sexual contacts, or sexual contact with a partner who has had syphilis, or a high number of sexual contacts. Along with the history, the presence of a chancre, usually in the genital area, will suggest primary syphilis, as will the presence of enlarged lymph nodes. With secondary syphilis, numerous other signs can provide a clue, including a rash on the torso, arms and legs, soles and palms, patches of mucous in the mouth, particular lesions around the genitals and anus, patches of baldness, and various features in the eyes. Tertiary syphilis also shows various signs in the heart an in mental function, slurred speech and several features in the eyes. Bones, skin, and the tissues in between also can be affected, leading to disfigurement, such as loss of a nose or other body parts.

Diagnosis of syphilis is made in the laboratory, with a couple of different blood tests. Pregnancy can make these tests falsely positive, meaning that they can come out positive when you actually don’t have a syphilis infection. However, diagnosis is confirmed either by observing the T. pallidum organism on what’s called darkfield microscopy, or after performing what’s called polymerase chain reaction (PCR) to amplify DNA whose sequence then can be read to identify the organism. When neurosyphilis is suspected, doctors may also draw samples of fluid from around your spinal cord in a procedure called a lumbar puncture. When cardiovascular syphilis is suspected, the chest will be imaged and doctors will perform various tests on the heart itself.

Syphilis is one of the notorious TORCH infectious diseases that cause terrible problems in the newborn. During the late latency period, T. pallidum can spread through the placenta and infect the fetus, leading to congenital syphilis. This can cause stillbirth, or leave a surviving newborn very small, with a rash, and with various defects in the bones and teeth.

The preferred treatment for syphilis is penicillin G, an old medication that still works very well, but it must be injected, not taken orally. It is not considered dangerous in pregnancy, but an alternative medication, called doxycycline, given to people who are allergic to penicillin, must be avoided in pregnant women. In the case of penicillin allergy in pregnant women with syphilis, the option is a procedure called desensitization treatment, which makes the women less sensitive to penicillin. Certain other antibiotics can be used as well.

David Warmflash
Dr. David Warmflash is a science communicator and physician with a research background in astrobiology and space medicine. He has completed research fellowships at NASA Johnson Space Center, the University of Pennsylvania, and Brandeis University. Since 2002, he has been collaborating with The Planetary Society on experiments helping us to understand the effects of deep space radiation on life forms, and since 2011 has worked nearly full time in medical writing and science journalism. His focus area includes the emergence of new biotechnologies and their impact on biomedicine, public health, and society.

Leave a Reply