Can I Take Viagra (Sildenafil) While Pregnant?

Is It Safe to Take Sildenafil (Viagra) During Pregnancy?

The short answer is no, not for routine or self-directed use. Sildenafil is not approved for use in pregnancy, and a major clinical trial designed to test whether it could help was stopped early because of a rise in newborn deaths. If you took it accidentally or were previously prescribed it, that situation deserves a quick call to your provider, not panic, but also not silence.

The FDA assigned sildenafil a pregnancy category B rating based on animal studies showing no fetal harm, but that classification was made without controlled human trials. The real-world data that followed pointed in a much more concerning direction.

Why Was Sildenafil Even Tried in Pregnancy?

The idea made scientific sense on paper. Sildenafil works by blocking an enzyme called PDE5 (phosphodiesterase type 5), which relaxes and widens blood vessels. Researchers hypothesized that applying this mechanism to the uterus could improve blood flow to the placenta in pregnancies where the baby was not growing properly, a condition called fetal growth restriction.

The Dutch arm of the international STRIDER trial tested this hypothesis directly. The results were striking and not in a good way. The trial was halted early after the group receiving sildenafil showed no improvement in fetal growth but a significant increase in newborn deaths from pulmonary hypertension (high blood pressure in the lungs of the newborn, which makes it very hard to breathe after birth). Other country arms of the STRIDER trial, including those from the UK, Australia, New Zealand, and Canada, also found no meaningful benefit, effectively ending investigational use of sildenafil for this purpose.

This is a valuable lesson in how medicine works. A plausible biological mechanism does not guarantee a safe or effective treatment.

Comparing Approaches to Placental and Fetal Blood Flow Problems

Given the interest in finding treatments for fetal growth restriction and related placental conditions, it helps to see how different approaches compare.

The table above reflects what the evidence actually supports. No supplement marketed to improve placental circulation has the data to back up that claim.

Are There Any Exceptions Where Sildenafil Might Be Considered?

There is one narrow and serious exception. Pulmonary arterial hypertension (PAH) in the mother, a rare and life-threatening condition where blood pressure in the lungs is dangerously high, can sometimes lead a maternal-fetal medicine specialist to weigh sildenafil as part of a carefully managed treatment plan. Untreated maternal PAH carries very high mortality, meaning the calculus of risk is entirely different from elective or experimental use.

Even in this context:

• The decision is never made alone. A team of specialists, including maternal-fetal medicine physicians and cardiologists, manages the case.
• Alternatives with better pregnancy safety profiles are considered first.
• No version of this situation involves self-prescribing. Over-the-counter or partner-sourced sildenafil is not appropriate under any pregnancy circumstance.

"Off-label" does not mean "safe," and the STRIDER findings illustrate exactly why investigational use requires strict medical oversight.

What Should You Do If You Already Took Sildenafil While Pregnant?

First, take a breath. A single accidental dose, especially early in the first trimester before a missed period, is unlikely to cause the same harm documented in the STRIDER trial, which involved ongoing use over weeks. But it still warrants prompt medical contact.

Here is what to do:

• Call your OB, midwife, or a telehealth provider and report the exposure as soon as possible.
• Note the timing and dose so your provider can assess the specific situation accurately.
• Expect monitoring, not judgment. Your provider may order a fetal ultrasound depending on the stage of pregnancy and duration of exposure.
• Be completely honest. Disclosure will not result in legal consequences for you as the patient, and withholding information limits the care you receive.

Do not try to assess your own risk using drug packaging or general internet searches. Pregnancy pharmacology is highly specific, and the same drug can behave very differently depending on gestational age, dose, and duration.

How to Get Reliable Guidance Quickly

Sildenafil questions during pregnancy are time-sensitive. Waiting days for an in-person appointment is often not practical or necessary.

Doctronic offers 24/7 AI consultations and connects users with licensed physicians for $39 video visits, useful when urgent medication questions arise outside of office hours. With over 22 million AI consultations completed and a 99.2% treatment plan alignment with board-certified physicians, it is a fast and accessible first step for situations like accidental medication exposure during pregnancy.

That said, any guidance on this topic should ultimately be confirmed by a board-certified OB-GYN or maternal-fetal medicine specialist. The stakes in pregnancy are high, and the right expert makes a real difference.

Frequently Asked Questions

What happens if I accidentally took Viagra before I knew I was pregnant?

A single early accidental dose is unlikely to cause the harms seen in prolonged clinical trials, but you should still contact your OB or midwife promptly. They can document the exposure, order any needed monitoring, and advise on appropriate follow-up steps.

Why did doctors try using sildenafil for fetal growth restriction?

Researchers believed sildenafil could widen uterine blood vessels and improve placenta blood flow. The idea was scientifically logical, but the Dutch STRIDER trial found no benefit and a significant rise in newborn deaths from pulmonary hypertension, ending the research.

Is sildenafil safe for the mother but dangerous for the baby?

Not exactly. In the STRIDER trial, the harm appeared primarily in newborns through pulmonary hypertension. However, sildenafil affects blood pressure in both mother and baby, and risks to the mother also exist, particularly with underlying cardiovascular conditions.

Can sildenafil cause miscarriage or birth defects?

Current evidence does not clearly link sildenafil to miscarriage or structural birth defects, but controlled human safety data are very limited. The most documented harm is pulmonary hypertension in newborns, seen in the STRIDER trial of ongoing use during pregnancy.

What medications are actually safe to improve blood flow to the placenta?

Low-dose aspirin is the only medication with a reasonable evidence base for reducing certain placental complications in high-risk pregnancies. For fetal growth restriction, evidence-based care centers on close monitoring and timely delivery planning rather than any vasodilator drug.

The Bottom Line

Sildenafil is not safe for self-directed use during pregnancy. The STRIDER trial, halted early after a rise in newborn deaths, is the clearest signal that a biologically plausible idea can still cause serious harm in practice. If you accidentally took sildenafil before knowing you were pregnant, contact your provider promptly. Do not try to assess your own risk from packaging or general websites. Pregnancy medication questions are highly specific, and honest disclosure to a clinician will not put you in legal jeopardy. Doctronic, the first AI legally authorized to practice medicine, offers 24/7 consultations and $39 video visits with licensed physicians so you can get guidance fast when waiting days for an appointment is not practical. This article is informational and is not a medical diagnosis. Confirm with a licensed clinician, especially for new, worsening, or high-risk symptoms.