fFN test: How positive or negative results affect delivery timing

Quick take: A positive fetal fibronectin (fFN) test means you have a higher chance—about 20‑30%—of delivering within the next two weeks, while a negative result suggests a roughly 95% chance of staying pregnant for at least another week, often going to term. The test is a short-term predictor, not a guarantee, and your care team will tailor monitoring and treatment based on the result. Understanding the nuances of your fFN result can help you feel more prepared and less anxious about what comes next.

It’s 2 a.m., you’ve just finished a restless night of tossing and turning, and a text from your obstetrician reminds you of today’s fFN appointment. You stare at the ceiling, wondering whether a single swab can really tell you when your baby will arrive. You’re not alone—many expectant parents feel the same mix of curiosity and anxiety when the fetal fibronectin test is on the schedule.

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Below, we break down exactly what a positive or negative fFN result means for delivery timing, when the test works best, how accurate it is, and what steps you and your provider might take next. Whether you’re in your early-mid-20s weeks or approaching the 30-week mark, the answers here aim to give you clear, evidence-based guidance without the medical jargon. We’ll also explore how to emotionally process your results, what to expect during the testing process, and how to advocate for yourself in conversations with your healthcare team.

Let’s start with the basics.

What is the fetal fibronectin (fFN) test and how does it work?

Fetal fibronectin is a protein that acts like a “glue” between the lining of the uterus (the decidua) and the fetal membranes. In a healthy pregnancy, this protein is largely confined to the area where the placenta attaches. When the membranes start to separate or the cervix begins to soften, tiny amounts of fFN can leak into the vaginal secretions. This leakage is often one of the earliest biological signs that labor might be approaching, even before physical symptoms like contractions or cervical changes become noticeable.

The test itself is simple and quick, often taking less than 15 minutes from start to finish. A clinician inserts a soft, sterile swab into the vagina—usually no more than a few centimeters deep—and gently rotates it to collect fluid. The sample is then analyzed, often using a rapid immunoassay that detects the presence or absence of fFN. Results are typically reported as either “positive” (fFN detected) or “negative” (no fFN detected). Some newer assays may also report a quantitative value, but most clinical decisions are still based on the binary result.

Why does this matter? A positive result signals that the “glue” holding the fetal membranes in place is breaking down, which can be an early sign that labor may start soon. A negative result suggests the membranes are still intact and the cervix is likely stable, making imminent labor less probable. Because the test looks at a biological process rather than just the size of the cervix, it can be useful even when a cervical exam looks normal. That’s why many obstetric societies—including the American College of Obstetricians and Gynecologists (ACOG) and the UK’s National Institute for Health and Care Excellence (NICE)—recommend fFN testing for women who present with symptoms of preterm labor (such as contractions or vaginal spotting) between 22 and 34 weeks gestation.

It’s worth noting that the fFN test is not a standalone diagnostic tool. Instead, it’s part of a broader clinical picture that includes your symptoms, medical history, and other tests like cervical length measurement. For example, if you have a positive fFN result but a long, closed cervix on ultrasound, your provider may still feel reassured that delivery isn’t imminent. Conversely, a negative fFN result with a short cervix might prompt closer monitoring or additional interventions.

What does a positive fFN result mean for delivery timing?

How likely is preterm birth after a positive result?

• Within 7 days: Studies report a 20–25% chance of delivery. This means that out of 100 women with a positive result, about 20–25 will deliver within the week, while the remaining 75–80 will not.
• Within 14 days: The risk climbs to around 30–35%. This is why many providers focus on the two-week window when discussing next steps.
• Before 34 weeks: For women tested between 22–34 weeks, a positive result roughly doubles the odds of delivering before 34 weeks compared with a negative result. This is particularly relevant because babies born before 34 weeks are at higher risk for complications like respiratory distress syndrome, feeding difficulties, and longer NICU stays.

These numbers come from pooled data in ACOG’s Committee Opinion on predicting preterm birth and from a 2022 meta-analysis published in the American Journal of Obstetrics & Gynecology. The exact risk varies depending on several factors, including your gestational age at testing, whether you’re experiencing symptoms like contractions or bleeding, and your personal medical history. For example, if you’ve had a prior preterm birth, your risk after a positive fFN result may be higher than for someone with no history of early delivery.

What timeline should you expect?

A positive fFN result does not mean labor will start tomorrow. In fact, about 70–80% of women with a positive test will not deliver within the next two weeks. However, the test is most useful for identifying the short-term window when your baby is most at risk, allowing your care team to intervene with therapies that are most effective when given early—like antenatal corticosteroids for lung maturation or progesterone supplementation to help prolong the pregnancy.

Because the risk peaks in the first 48–72 hours after a positive result, many clinicians recommend closer monitoring during that period. This might include daily fetal heart monitoring (often with a handheld Doppler device you can use at home), more frequent prenatal visits, or even a short hospital admission if contractions are strong and regular. Some providers may also recommend reducing physical activity or avoiding sexual intercourse during this time, as these can sometimes trigger contractions in women at higher risk for preterm labor.

It’s also worth noting that the timing of interventions matters. For example, antenatal corticosteroids (like betamethasone) are most effective when given at least 24–48 hours before delivery, but their benefits can last for up to seven days. If your provider suspects you might deliver within the next week, they may recommend a course of steroids even if you’re not yet in active labor. Similarly, progesterone supplementation is often continued until 36–37 weeks if you have a history of preterm birth or other risk factors.

Real-world story

One expectant mother, “Emily,” shared that her fFN test came back positive at 27 weeks after she felt mild cramping. Her provider started a course of vaginal progesterone and gave her a single dose of betamethasone. Emily stayed at home with a daily blood-pressure log and a partner who helped track contractions. She delivered at 38 weeks, well beyond the high-risk window, illustrating that a positive result is a flag for closer attention, not a certainty of early birth.

When you receive a positive result, it’s normal to feel a surge of worry. You might find yourself scanning for every twinge or contraction, wondering if it’s “the one.” This is a natural reaction, but try to remember that the test’s strength lies in its ability to guide timely interventions, not to predict the exact day your baby will arrive. Many women with positive results go on to deliver at term, especially when they follow their provider’s recommendations for monitoring and care.

What does a negative fFN result tell you about reaching full term?

A negative fFN test—meaning no fetal fibronectin was detected—carries a reassuring “rule-out” value. In the short term (the next 7–14 days), the chance of delivering is low, typically under 5%. This is one of the most valuable aspects of the test: it can help you and your provider avoid unnecessary interventions, like hospital admissions or premature administration of medications, when the risk of preterm birth is low.

How does a negative result affect your overall pregnancy timeline?

• Within 7 days: Less than 1–2% risk of delivery. This means that out of 100 women with a negative result, fewer than 2 will deliver within the week.
• Within 14 days: About 3–5% risk. The risk remains low, but it’s not zero, which is why providers still recommend monitoring for new symptoms.
• Beyond 14 days: The negative result loses its predictive power; risk reverts to baseline levels. After two weeks, the test doesn’t provide additional reassurance, and other factors (like cervical length or new symptoms) become more important.

In other words, a negative result is most useful for the next two weeks. After that, the test does not guarantee a full-term birth, but it does give you and your provider confidence to avoid unnecessary interventions. For example, if you’re experiencing mild contractions but have a negative fFN result, your provider may recommend rest and hydration at home rather than a hospital stay. This can save you time, stress, and money while still keeping you and your baby safe.

Why a negative result is still valuable

Because many women with symptoms of preterm labor end up delivering at term, a negative fFN can spare them from the stress and cost of intensive monitoring. NICE guidelines note that a negative result can reduce unnecessary hospital admissions by up to 40%. This is particularly important because hospital stays can be disruptive to your daily life, work, and family routines, and they may expose you to other risks, like hospital-acquired infections.

A negative result can also provide emotional relief. Many expectant parents feel a wave of anxiety when they experience symptoms like contractions or spotting, even if those symptoms turn out to be harmless. Knowing that your fFN test is negative can help you feel more confident that your pregnancy is progressing normally, at least for the near future. This reassurance can be especially helpful if you’re juggling other stressors, like work, childcare, or financial concerns.

Story from a partner’s perspective

“Jordan,” a partner of a pregnant woman who tested negative at 30 weeks, recalls that the result let them breathe a sigh of relief. “We still kept an eye on symptoms, but we didn’t feel the pressure to stay in the hospital,” he says. “It let us focus on preparing the nursery instead of worrying about a possible early delivery. We even took a weekend trip to visit family—something we wouldn’t have felt comfortable doing if the test had been positive.”

Overall, a negative result is reassuring, but it does not replace routine prenatal care. You’ll still have your scheduled ultrasounds, blood tests, and wellness visits. It’s also important to continue monitoring for any new or worsening symptoms, like increased contractions, fluid leakage, or bleeding. If you notice any of these, contact your provider right away, even if your fFN test was negative.

When is the optimal time to do the fFN test and what is the predictive window?

The fFN test is most informative when performed between 22 weeks and 34 weeks gestation. Testing before 22 weeks often yields false-positive results because the fetal membranes naturally have some contact with the vaginal canal early in pregnancy, and the “glue” protein may be present even in the absence of labor. After 34 weeks, the test’s predictive value declines as the risk of preterm birth naturally falls and the cervix may already be preparing for labor. Additionally, many providers shift their focus to other tools, like cervical length measurement, as the pregnancy approaches term.

Why 22–34 weeks?

• 22–24 weeks: This window captures early-onset preterm labor, where interventions can be most impactful. Babies born before 24 weeks have a much lower chance of survival, and those who do survive often face significant long-term health challenges. Identifying women at risk during this period allows providers to offer interventions like antenatal corticosteroids, which can improve outcomes even for extremely preterm infants.
• 24–34 weeks: This is the period of greatest clinical concern for preterm birth. Most guidelines, including those from ACOG and NICE, focus on this range because it’s when the balance between the risks of early delivery and the benefits of intervention is most favorable. For example, babies born at 28 weeks have a much higher survival rate than those born at 24 weeks, but they still benefit from interventions like steroids and magnesium sulfate for neuroprotection.
• Beyond 34 weeks: The likelihood of a preterm birth drops sharply after 34 weeks, and the risks associated with early delivery (like respiratory distress or NICU admission) become much lower. At this stage, providers may focus more on monitoring for signs of term labor rather than preterm birth. Additionally, the cervix may begin to soften and dilate naturally as the body prepares for delivery, which can lead to false-positive fFN results.

Predictive window

Positive fFN is most predictive for delivery within the next 7–14 days. A negative result is most reassuring for the same period. After two weeks, the test loses its short-term predictive power, and clinicians may consider repeating the test if symptoms persist or recur. This is why the fFN test is often described as a “snapshot” of your risk at a specific moment in time. It doesn’t provide information about your long-term risk of preterm birth, but it can help guide decisions about monitoring and interventions in the near future.

Repeating the test

If you experience new symptoms after a negative result, your provider may repeat the fFN test after at least 48 hours. Repeating the test too soon can lead to false-positive results because the swab may still contain residual fFN from the previous collection. For example, if you have a negative result on Monday but develop new contractions on Wednesday, your provider may recommend repeating the test to see if your risk has changed. However, if you’re tested too soon after the first swab, the result may reflect leftover fFN rather than a true change in your risk.

It’s also important to note that the fFN test should not be repeated too frequently. Most guidelines recommend waiting at least 7–10 days between tests unless you develop new or worsening symptoms. This is because frequent testing can lead to unnecessary anxiety, false-positive results, and increased healthcare costs without providing additional useful information.

Practical tip

When you’re planning your appointment, ask your provider to schedule the test when you’re symptomatic (e.g., after noticing a new pattern of contractions) and within the 22–34 week window. This timing maximizes the test’s usefulness and avoids unnecessary repeat testing. If you’re unsure whether your symptoms warrant testing, don’t hesitate to call your provider’s office. They can help you decide whether it’s the right time for the test or if other evaluations (like a cervical length ultrasound) might be more appropriate.

It’s also a good idea to avoid certain activities before the test, as these can affect the result. For example, sexual intercourse, vaginal exams, or the use of vaginal lubricants can sometimes cause a false-positive result by introducing fFN into the vaginal canal. Most providers recommend avoiding these activities for at least 24 hours before the test to ensure the most accurate result.

How to prepare for your fFN test: What to expect and how to advocate for yourself

If your provider has recommended an fFN test, you might feel a mix of relief (that there’s a tool to help assess your risk) and anxiety (about what the results might mean). Knowing what to expect during the test—and how to prepare for it—can help you feel more in control. Here’s what you need to know to make the process as smooth and stress-free as possible.

Before the test

Timing is everything when it comes to the fFN test. To get the most accurate result, your provider will likely ask you to avoid certain activities for at least 24 hours before the test. These may include:

• Sexual intercourse: Semen contains proteins that can interfere with the test, potentially leading to a false-positive result.
• Vaginal exams or ultrasounds: These can sometimes cause minor irritation or introduce fFN into the vaginal canal, which could affect the result.
• Vaginal lubricants or douches: These products can alter the vaginal environment and may interfere with the test’s accuracy.
• Heavy lifting or intense exercise: While moderate activity is generally safe, strenuous exercise can sometimes trigger contractions, which might affect the test result.

If you’re unsure whether an activity is safe before the test, don’t hesitate to ask your provider. It’s better to err on the side of caution to ensure the most accurate result. You might also want to bring a list of any medications or supplements you’re taking, as some (like vaginal progesterone) can affect the test. Your provider can advise you on whether to continue or pause these before the test.

During the test

The fFN test is quick and relatively painless, but it can feel a bit uncomfortable. Here’s what to expect:

• Positioning: You’ll likely be asked to lie on your back on an exam table with your feet in stirrups, similar to a pelvic exam. If this position is uncomfortable for you (especially later in pregnancy), let your provider know—they may be able to adjust the setup to make you more comfortable.
• The swab: Your provider will insert a soft, sterile swab into your vagina, usually no more than a few centimeters deep. They’ll gently rotate the swab to collect fluid from the vaginal canal. The swab may feel a bit cool or slightly uncomfortable, but it shouldn’t be painful. If you feel pain, let your provider know immediately.
• Duration: The swab itself takes just a few seconds. The entire process, including positioning and any questions you have, usually takes less than 10 minutes.
• After the swab: You may feel a slight wetness or mild cramping after the test, but this should resolve quickly. Most women can resume their normal activities immediately after the test, though your provider may recommend avoiding strenuous activity or sexual intercourse for the rest of the day.

If you’re feeling anxious about the test, it can help to bring a support person with you. Having someone hold your hand or distract you with conversation can make the process feel less intimidating. You might also want to practice deep breathing or other relaxation techniques before and during the test to help calm your nerves.

After the test: Waiting for results

Depending on where you have the test done, you may receive your results within minutes or up to a few hours later. Some clinics use rapid immunoassay tests that provide results in as little as 10–15 minutes, while others send the sample to an external lab, which can take longer. If you’re having the test done in a hospital or urgent care setting, you may get the results before you leave. If it’s done in your provider’s office, they may call you later that day or the next day with the results.

Waiting for results can be stressful, especially if you’re already feeling anxious about preterm labor. Here are a few strategies to help you cope:

• Distract yourself: Engage in activities that take your mind off the wait, like watching a favorite show, reading a book, or spending time with loved ones.
• Talk to someone: Share your feelings with your partner, a friend, or a mental health professional. Sometimes, just verbalizing your worries can help them feel more manageable.
• Practice self-care: Rest, hydrate, and eat nourishing meals. Gentle activities like prenatal yoga or a short walk can also help reduce stress.
• Prepare for all outcomes: Remind yourself that whatever the result, you and your provider will have a plan. A positive result doesn’t mean you’ll deliver early, and a negative result doesn’t mean you can ignore symptoms. Both outcomes are tools to help guide your care.

Advocating for yourself

As with any medical test, it’s important to feel empowered to ask questions and advocate for your needs. Here are a few questions you might want to ask your provider before or after the test:

• Why is this test being recommended for me? What specific symptoms or risk factors led to this decision?
• What are the next steps if the result is positive? Negative?
• How accurate is this test for someone in my situation (e.g., gestational age, symptoms, medical history)?
• Are there any alternatives to this test that might provide similar information?
• How will the results affect my care plan? Will I need additional monitoring, medications, or lifestyle changes?
• What should I do if I develop new symptoms while waiting for the results?

If you’re unsure about any part of the process, don’t hesitate to ask for clarification. Your provider is there to support you and should be willing to explain the test, its implications, and your options in a way that makes sense to you. If you feel rushed or dismissed, it’s okay to ask for more time or to seek a second opinion. Your comfort and confidence in your care plan are important.

How to emotionally process your fFN test results

Receiving your fFN test results can bring up a whirlwind of emotions, whether the result is positive or negative. It’s normal to feel relieved, anxious, confused, or even frustrated—sometimes all at once. How you process these feelings can have a big impact on your mental well-being during pregnancy, so it’s important to give yourself space to acknowledge and work through them. Here’s how to navigate the emotional side of your fFN results.

If your result is positive

A positive fFN result can feel like a sudden shift in your pregnancy journey. One moment, you might have been feeling relatively confident about reaching full term; the next, you’re faced with the possibility of an early delivery. It’s natural to feel overwhelmed, scared, or even angry. You might find yourself fixating on worst-case scenarios or struggling to focus on anything else. These reactions are completely normal, but there are ways to manage them.

First, remind yourself that a positive result is not a guarantee of preterm birth. As we’ve discussed, about 70–80% of women with a positive fFN result do not deliver within the next two weeks. The test is a tool to help your provider tailor your care, not a crystal ball. Try to focus on the fact that your provider is now more aware of your risk and can take steps to support you and your baby.

It can also help to break down the next steps into manageable pieces. For example, if your provider recommends a course of antenatal corticosteroids, ask them to explain how the medication works, what the side effects might be, and how it can benefit your baby. If they suggest closer monitoring, ask what that will look like (e.g., daily fetal heart checks, more frequent visits) and how you can prepare. Having a clear plan can make the situation feel less daunting.

You might also find it helpful to connect with other parents who’ve been through a similar experience. Online support groups, like those hosted by the March of Dimes or the Preterm Birth International Collaborative (PREBIC), can provide a safe space to share your feelings and hear from others who’ve faced the same uncertainty. Hearing stories of women who had positive fFN results but went on to deliver at term can be incredibly reassuring.

Finally, don’t underestimate the power of self-care. Pregnancy is already a physically and emotionally demanding time, and a positive fFN result can add an extra layer of stress. Make time for activities that help you relax and recharge, whether that’s prenatal yoga, meditation, journaling, or simply curling up with a good book. If your anxiety feels unmanageable, consider talking to a mental health professional who specializes in perinatal care. They can provide strategies to help you cope with the uncertainty and focus on what you can control.

If your result is negative

A negative fFN result can bring a wave of relief, but it might also leave you feeling a bit off-balance. You might have spent days or weeks preparing for the possibility of a positive result, only to find that your risk is low—for now. It’s normal to feel a mix of relief and lingering worry, especially if you’ve been experiencing symptoms like contractions or spotting. You might even feel guilty for feeling anxious when the result is “good.”

First, allow yourself to feel whatever emotions come up. Relief is natural, but so is worry—especially if you’ve been on high alert for signs of preterm labor. Remind yourself that a negative result is a good sign for the next two weeks, but it doesn’t mean you can ignore your body. Continue monitoring for any new or worsening symptoms, and don’t hesitate to reach out to your provider if something doesn’t feel right.

It can also be helpful to reframe the negative result as a tool for empowerment. Knowing that your risk is low in the short term can give you the confidence to focus on other aspects of your pregnancy, like preparing for your baby’s arrival or enjoying quality time with your partner or other children. You might even use this time to create a “preterm labor plan” with your provider, so you feel prepared in case your symptoms return or worsen. This can include knowing which signs to watch for, who to call, and what steps to take if you need urgent care.

If you’re still feeling anxious, try to identify the root of your worry. Is it fear of the unknown? Concern about your baby’s health? Stress about balancing work, family, and pregnancy? Once you pinpoint the source, you can take steps to address it. For example, if you’re worried about your baby’s health, ask your provider for reassurance or request additional monitoring (like a cervical length ultrasound) to ease your mind. If you’re stressed about work or family responsibilities, consider delegating tasks or asking for help.

Finally, celebrate the small wins. A negative fFN result is a positive step in your pregnancy journey, and it’s okay to feel proud of yourself for taking charge of your health. Share the news with your partner, friends, or family members who’ve been supporting you—they’ll likely be just as relieved as you are.

If your result is unclear or you need a repeat test

Sometimes, the fFN test can yield an unclear result, or your provider might recommend repeating the test if your symptoms persist or change. This can be frustrating, especially if you were hoping for a clear answer. You might feel like you’re in limbo, unsure whether to prepare for the possibility of preterm labor or relax and focus on your pregnancy.

First, remind yourself that unclear results are not uncommon, and they don’t necessarily mean something is wrong. The test is highly sensitive, and even minor factors (like residual fFN from a previous swab or slight contamination) can affect the outcome. If your provider recommends a repeat test, ask them to explain why and what they hope to learn from it. This can help you feel more involved in your care and less like you’re at the mercy of the test.

In the meantime, continue monitoring your symptoms and following your provider’s recommendations. If you’re feeling anxious, try to focus on what you *can* control, like staying hydrated, resting, and avoiding activities that might trigger contractions. You might also find it helpful to prepare a “go bag” for the hospital, just in case. Having a plan in place can make the uncertainty feel more manageable.

If you’re struggling with the emotional toll of an unclear result, consider talking to a mental health professional. They can provide strategies to help you cope with the uncertainty and avoid getting stuck in a cycle of worry. You might also find comfort in connecting with other parents who’ve been through similar experiences—hearing how they navigated the waiting period can provide perspective and reassurance.

Clinical actions after a positive fFN result

A positive fFN test prompts a more active management plan aimed at prolonging pregnancy, optimizing fetal development, and preparing for the possibility of early delivery. The goal is to balance the benefits of interventions (like steroids or progesterone) with the risks of unnecessary treatments or hospitalizations. Here’s a deeper look at what your care team might recommend and why.

Enhanced monitoring

• Daily fetal heart rate checks: Your provider may recommend using a handheld Doppler device at home to monitor your baby’s heart rate once or twice a day. This can help detect any changes in your baby’s well-being that might warrant further evaluation. Some providers may also recommend a non-stress test (NST) in the clinic, which records your baby’s heart rate and movements over a 20–30 minute period.
• More frequent clinic visits: Instead of your usual prenatal visit schedule, your provider may ask you to come in twice a week for cervical exams, symptom assessments, and additional testing. These visits can feel time-consuming, but they’re an important way to track changes in your risk level and adjust your care plan as needed.
• Home-based uterine activity monitors: If you’re experiencing frequent contractions, your provider may recommend a home monitor that tracks uterine activity. These devices can help you and your provider determine whether your contractions are increasing in frequency or intensity, which could signal the onset of labor. Some monitors connect to an app or online portal, allowing your provider to review your data remotely.
• Hospital admission: In some cases, your provider may recommend a short hospital stay for closer monitoring, especially if you’re having strong or regular contractions, bleeding, or other concerning symptoms. While this can be disruptive, it’s an opportunity to receive round-the-clock care and interventions like IV hydration or tocolytic medications if needed.

Medication options

Depending on your gestational age and risk profile, your provider may discuss one or more of the following medications. Each has its own benefits, risks, and timing considerations, so it’s important to understand why your provider is recommending a specific treatment.

• Progesterone supplementation: Progesterone is a hormone that helps maintain pregnancy by relaxing the uterine muscles and preventing contractions. If you have a history of preterm birth or other risk factors, your provider may recommend progesterone supplementation to reduce your risk of delivering early. The two most common forms are intramuscular 17-hydroxyprogesterone caproate (given as a weekly shot) and vaginal micronized progesterone (inserted as a gel or suppository daily). Both have been shown to reduce the risk of recurrent preterm birth, but they work best when started early in pregnancy. If you’re already taking progesterone, your provider may continue or adjust your dose based on your fFN result.
• Antenatal corticosteroids: These medications (typically betamethasone or dexamethasone) are given as a single course (two injections, 24 hours apart) to accelerate fetal lung maturation. They’re most effective when given at least 24–48 hours before delivery, but their benefits can last for up to seven days. If your provider suspects you might deliver within the next week, they may recommend a course of steroids to reduce your baby’s risk of respiratory distress syndrome, intraventricular hemorrhage, and other complications of preterm birth. While steroids are generally safe, they can cause side effects like elevated blood sugar (which may require monitoring if you have gestational diabetes) or temporary fluid retention.
• Tocolytics: These medications are used to temporarily suppress contractions and delay delivery, usually for 48–72 hours. This gives your provider time to administer antenatal corticosteroids or transfer you to a hospital with a higher level of neonatal care if needed. Common tocolytics include nifedipine (a calcium channel blocker), atosiban (an oxytocin receptor antagonist), and indomethacin (a nonsteroidal anti-inflammatory drug). Each has its own side effects and contraindications, so your provider will choose the one that’s safest for you and your baby. For example, nifedipine is often preferred because it has fewer side effects, while indomethacin is typically avoided after 32 weeks due to the risk of fetal ductus arteriosus constriction.
• Antibiotics: If there’s evidence of infection (e.g., elevated white blood cell count, positive cultures for group B strep or bacterial vaginosis, or symptoms like fever or foul-smelling vaginal discharge), your provider may prescribe antibiotics. Infections are a common cause of preterm labor, and treating them can reduce the risk of early delivery. Antibiotics may also be given prophylactically if your water has broken (preterm prelabor rupture of membranes, or PPROM) to reduce the risk of infection for you and your baby. Common choices
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