How the most common STIs can impact trying to get pregnant

Jenn Conti, MD, MS, MSc - Contributor Avatar

Written by Rachel Sanoff 

Jenn Conti, MD, MS, MSc - Contributor Avatar

Written by Rachel Sanoff 

last updated: Mar 30, 2021

9 min read

It’s too difficult to get the information we need about sexually transmitted infections (STIs). The topic often feels hush-hush, even among friends, and contracting an STI comes with unfair stigma and shame that can make talking to providers complicated.

But the truth is that STIs are incredibly common and, just like any other infection, they’re nothing to be ashamed of. In fact, 50% of sexually active people will contract an STI before the age of 25, according to the American Sexual Health Association.

“I always remind patients that (pre-COVID) they wouldn’t be ashamed of catching a cold, and in the same way, there’s no reason to be ashamed of catching a viral or bacterial infection on the opposite end,” says Dr. Jenn Conti, MD, MSc, FACOG, OB-GYN and Modern Fertility medical advisor. “Infections happen and, luckily, we have ways to treat them.”

Whether you’re trying to conceive, currently pregnant, or thinking about having kids down the road, we’re breaking down everything you need to know about STIs and pregnancy.

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The biggest takeaways

  • Yes, you can get pregnant with most STIs. If you’re actively trying to conceive, your healthcare provider may recommend preconception STI testing (through a blood test) so that any infections curable by medication (such as gonorrhea and chlamydia) are treated before you ever get pregnant.

  • If an STI is left untreated, that can lead to pelvic inflammatory disease (PID) and affect fertility.

  • While bacterial STIs — like chlamydia, gonorrhea, and syphilis — can impact pregnancy, they can be cured through a course of medication, either before conceiving or during pregnancy and childbirth.

  • Viral STIs — like HIV, HPV, herpes, and hepatitis B — are lifelong but can be managed with medication to mitigate pregnancy complications.

  • You can protect yourself against STIs during pregnancy by using barrier contraceptives, like condoms or dental dams.

First, why are we calling them STIs instead of STDs?

This is an important distinction. Even though STD (sexually transmitted disease) is a commonly used term, diseases generally refer to medical problems with obvious signs or symptoms. The “I” in STI stands for infections — which often have mild symptoms that can be overlooked, or no symptoms at all. That means it’s possible for people to have STIs they don’t even know about, underscoring the importance of getting tested. The term STI is also thought to offer more broad and inclusive descriptions.Because an STI can be asymptomatic, that means it’s possible to have an infection without knowing you’ve contracted it. The vast majority of STIs can be managed through medication, but  in order to get treatment, you'll need to know you have the infection. That's why proactive screening is recommended and why we advocate for equipping yourself with as much sexual health information as possible.

Can you get pregnant with STIs?

Yes, you can get pregnant with most STIs. But if you’re actively trying to conceive, your healthcare provider may recommend preconception STI testing so that any infections curable by medication (such as gonorrhea and chlamydia) are treated before you ever get pregnant.

“We routinely screen everyone at the start of their pregnancy so that if there is an infection present, we can treat it as quickly and safely as possible,” Dr. Conti says. If you have viral STIs that aren’t curable by medication (such as herpes or HIV), you can still safely get pregnant — but your healthcare provider may take certain steps to mitigate risks (more on these later).

Can STIs ever affect fertility?

If an STI is left untreated, people with ovaries can develop pelvic inflammatory disease (PID) — an infection of the uterus, fallopian tubes, ovaries, and cervix — which can result in infertility. According to the Centers for Disease Control and Prevention (CDC), 10%-15% of women with chlamydia will develop PID. But remember, this refers to situations where chlamydia is not treated — which again drives home the importance of regular STI testing.

Chlamydia can result in these fallopian tube infections with mild or no symptoms, so the issue may continue undetected without testing and cause permanent damage that could potentially result in infertility. Similarly, untreated gonorrhea can spread into the uterus and fallopian tubes, resulting in PID and potentially infertility — but you can undergo fertility treatments to try to conceive. “If PID was severe enough to distort the fallopian tube anatomy such that they are no longer functional, IVF is an alternative means of conception,” Dr. Conti explains. “We can bypass the tubes entirely and place an embryo directly into the uterus.”

Bacterial STIs that can affect pregnancy and birth

To start, let’s focus our attention on bacterial STIs that can be cured through a course of medication, either before conceiving or during pregnancy and childbirth.


Chlamydia is the most common bacterial STI in the United States, with four million chlamydia infections documented in 2018. You'll be screened for the infection at your first prenatal doctor's appointment.

Chlamydia can be asymptomatic, but the most common symptoms include discharge, pelvic pain, vaginal bleeding after penetrative sex, and painful urination. That said, chlamydia is curable with antibiotics.Pregnancy and birth risks: According to the CDC, untreated chlamydia during pregnancy can cause preterm labor or preterm rupture of membranes (or sacs surrounding the fetus), and low birth weight. If the baby is exposed to chlamydia during delivery, they may develop eye or lung infections.How can you treat chlamydia while pregnant?: The infection can be treated with antibiotics, and the infant will receive medication in their eyes at birth to prevent eye infections.


Gonorrhea and chlamydia are often contracted together. Symptoms for people with ovaries include painful urination, increased vaginal discharge, vaginal bleeding between periods, and pain in the abdomen or pelvis. It can be treated with antibiotics and is tested for during preconception STI screenings.

Pregnancy and birth risks: According to the CDC, gonorrhea is linked to miscarriage, preterm delivery, premature rupture of membranes, low birthweight, infections of the water and sac surrounding the fetus, and eye infections.

How can you treat gonorrhea while pregnant?: You’ll receive antibiotics to cure the infection, and just like with chlamydia, newborn infants are treated with eye medications at birth to ensure they don’t develop eye infections.


Syphilis is a bacterial STI on the rise in the US. There were over 115,000 documented infections in the US in 2020, and the Journal of the American Sexually Transmitted Diseases Association says that, worldwide, 2 million pregnant women have syphilis.

Symptoms for syphilis include sores, a full-body rash, and a sore throat, and it can lead to brain, nerve, and organ damage if left untreated. Once diagnosed, though, the infection can be cured with antibiotics, and you’ll be screened for syphilis at your preconception appointment.

Pregnancy and birth risks: Untreated syphilis during pregnancy and birth can have severe effects, including preterm birth, stillbirth, developmental delays, as well as vision and hearing difficulties — more reasons why regular STI testing and preconception appointments are so important.

How do you treat syphilis while pregnant?: Penicillin is currently the only antibiotic treatment for the infection, and the CDC recommends that pregnant people with penicillin allergies receive the antibiotic under medical supervision.

Viral STIs that can affect pregnancy and birth

While bacterial STIs can be cleared before or during pregnancy, viral STIs are lifelong but can be managed with medication. Next we’ll cover pregnancy when you have herpes, HIV, HPV, and hepatitis B — which can be safe with the right medical care.


Herpes simplex virus (HSV) is an incredibly common viral infection. According to the CDC, 1 out of every 6 people ages 14-49 have it. What’s more, according to the journal Infectious Diseases in Obstetrics and Gynecology, 22% of pregnant women in the US have genital herpes. For these reasons, doctors are very used to guiding patients with herpes through healthy pregnancies. Symptomatic herpes infections cause itching and burning in the genitals, which can evolve into sores.

There are two types of herpes: HSV-1 (which is typically associated with cold sores and known as oral herpes) and HSV-2 (which is typically associated with sores or blisters in the genital region and known as genital herpes). However, both HSV-1 and HSV-2 can affect your mouth and genitals, which is why getting a blood test for herpes is not that helpful — it doesn’t distinguish between run-of-the-mill cold sore virus or virus that could give you genital sores.

Pregnancy and birth risks: Herpes infection in newborns — known as neonatal herpes — can have more severe symptoms, including skin infections, severe brain infections, and other organ infections.

How can herpes impact your prenatal care?: Your OB-GYN will recommend a treatment plan based on how recently you contracted herpes and the timing of your outbreaks. If you already had herpes before conceiving and currently manage the infection with antiviral medication, the risk of transmitting it to your infant is very low. Dr. Conti says that if you have a history of genital herpes, your provider may start you on prophylactic antibiotics beginning at 36-weeks gestation in order to prevent any lesions from forming as your due date approaches.

If a pregnant person has been exposed to herpes for the first time, extra precautions will be taken to prevent transmission to the infant due to the pregnant person’s lack of antibodies.

If a pregnant person has an active outbreak when going into labor, an OB-GYN will recommend a Cesarean section (aka C-section) to lower the risk of transmission due to these serious side effects. Even if you’ve never had an outbreak but you’re herpes positive, your healthcare provider will still put you on antiviral suppression medications during the last few weeks of pregnancy to decrease the likelihood of an outbreak during labor.

Human papillomavirus (HPV)

Human papillomavirus (HPV) is the most common STI with 43 million infections documented in the US in 2018. There are multiple strains of HPV which can cause warts and/or precancerous changes to cervical cells, but that will likely have no negative impact on pregnancy. (Note that the CDC recommends that all patients be up to date with their cervical cancer screening even if they’re pregnant.)

Pregnancy and birth risks: HPV is not considered to have any impact on a fetus or baby. “The HPV virus largely confines itself to the vaginal and cervical tissue,” Dr. Conti explains. “It’s not the presence of the virus that concerns us mostly, but rather the effect it has on those tissues [for the birthing parent]. With HPV just confined to those tissues and in the absence of cancer, there is no known concern to the baby.”

Very rarely, if the pregnant person has genital warts caused by HPV during birth, the newborn can develop something called a laryngeal papillomatosis that must be treated by surgery — but a C-section almost eliminates that risk.

How can HPV impact your prenatal care?: Pregnancy hormones can increase wart breakouts in patients with HPV, and in these instances, warts can potentially obstruct the birth canal, leading some OB-GYNs to recommend a C-section.

Human immunodeficiency virus (HIV)

Human immunodeficiency virus (HIV) — the virus that causes AIDS — can be transmitted sexually or through blood and body fluid interactions like needle sharing.

Pregnancy and birth risks: Newborn babies can contract an HIV infection from a parent during pregnancy, birth, or while breastfeeding/chestfeeding, which would require the child to take antiviral medications for the rest of their life in order to keep the HIV manageable and undetectable. However, if a pregnant person receives an HIV diagnosis before or during pregnancy, they will be prescribed medication that can lower the risk of transmission to around 2%. For this reason, people trying to conceive are screened for HIV at their first prenatal visit and receive another screening again at 28 weeks.

How can HIV impact your prenatal care?: The most important thing is finding the right medical team that can help you have a healthy pregnancy and birth. “I always recommend working with a high-risk OB-GYN or maternal fetal medicine specialist because these are pregnancies that often need to be watched more closely," says Dr. Conti. You may want to find an OB-GYN who partners with other doctors who specialize in HIV care, and you might need to prepare for more check-up appointments than a pregnant person without HIV would.

You’ll continue to take antiviral medication throughout your pregnancy to keep viral load low, and if viral load is high, your OB-GYN may recommend a C-section at delivery to further reduce the risk of potential exposure at birth, according to the American College of Obstetricians and Gynecologists.

Hepatitis B

Hepatitis B is a viral infection of the liver that’s transmitted sexually or through blood exposure, then circulates through the bloodstream.

Pregnancy and birth risks: Infants can be infected with hepatitis B from a positive birthing parent during pregnancy and delivery. Of infants who contract the virus, 40% will develop chronic active hepatitis (chronic liver disease), and one-fourth of those infants will die from the liver disease.

How can hepatitis B impact prenatal care?: Treatment during pregnancy can considerably lower the risk of transmission to the fetus. Developing a treatment plan with your healthcare provider at a preconception appointment will help you start to protect your pregnancy immediately. Once patients trying to conceive are screened for hepatitis B, OB-GYNs coordinate care with high-risk doctors and pediatricians for people who carry the virus. As she recommends for pregnant patients with HIV, Dr. Conti also suggests people with active hepatitis receive treatment from a high-risk OB-GYN or a maternal fetal medicine specialist.If you’ve contracted hepatitis B, treatment includes antiviral medications that lower the amount of virus in your bloodstream, which then decreases chances of transmission. Once the infant is born, transmission rates can decrease further by giving the infant a hepatitis B vaccine and additional immunoglobulin that are specific to hepatitis B (aka virus-fighting particles made by the body in response to an infection).

How can you protect yourself against STIs while pregnant?

Sex during pregnancy is safe for most people — and even though conception won't be possible while pregnant, STI transmission will be. If you're pregnant and have new sex partners, it's important to use a barrier contraceptive, like condoms or dental dams, while engaging in sexual activity during pregnancy to protect yourself against STIs.

The bottom line

Your care provider will likely test for the whole gamut of STIs during your first prenatal appointment and some of these STIs can be completely cleared with antibiotics. As for the ones that can’t, it’s all about minimizing risk, and a trusted professional can help you do that — from getting antivirals ready to reduce the risk of a herpes outbreak to collaborating with a high-risk doctor to navigate delivery with hepatitis B.Beyond all of the precautions and planning, it’s also incredibly important to have support. Project Accept is an online community for folks with HSV and HPV. Also, hearing stories from others who are going through similar situations can make all the difference — we love this essay in Marie Claire about a woman conceiving with herpes. With nearly 20 million new STIs occurring every year, you’re absolutely not alone if you’re conceiving with an STI, and it's very possible to have a healthy pregnancy and safe live birth.


If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

How we reviewed this article

Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

March 30, 2021

Written by

Rachel Sanoff

Fact checked by

Jenn Conti, MD, MS, MSc

About the medical reviewer

Dr. Jenn Conti is an OB-GYN and serves as an adjunct clinical assistant professor at Stanford University School of Medicine.