The experience of hearing a rhythmic whooshing, thumping, or pulse-like sound in the ear, perfectly synchronized with your heartbeat, is known as pulsatile tinnitus. This sensation is a relatively common occurrence during pregnancy, affecting as many as one in three expectant mothers. It is a direct result of the normal physiological changes your body undergoes to support the developing fetus. The sound you perceive is the actual sound of blood moving through vessels close to the ear structure. This phenomenon is benign and tends to resolve spontaneously after delivery, once the body returns to its pre-pregnancy state.
Pregnancy’s Impact on Blood Flow
The primary driver of pulsatile tinnitus during pregnancy is the dramatic adaptation of the cardiovascular system. To meet the increased metabolic demands of the mother and the developing fetus, the body must pump significantly more blood. Blood volume expands dramatically, increasing by 30 to 50% by the third trimester.
This expanded volume requires the heart to work harder, causing the cardiac output—the volume of blood pumped per minute—to rise by a similar amount. The heart rate also increases by 10 to 20 beats per minute above the pre-pregnancy baseline. This combination of increased volume, faster flow, and higher pressure creates turbulent and louder sound within the blood vessels. When volume and velocity increase significantly, the flow becomes less smooth and more audible. This heightened internal noise is the source of the whooshing sound, and it is most often reported in the second and third trimesters.
How Pulsatile Sounds Reach the Inner Ear
The increased volume and turbulence of blood flow require a clear path to the auditory system to be heard. Large blood vessels in the head and neck, such as the internal carotid artery and the jugular vein, are located in close anatomical proximity to the ear structures. The turbulent noise from the blood rushing through these vessels is easily transmitted through the surrounding tissue and bone.
This conduction pathway allows the sound waves to travel directly to the cochlea, the organ responsible for hearing. The temporal bone, which houses the inner ear, acts like a conductor, transmitting the amplified sound of the blood flow directly to the hearing mechanism. Minor physical changes during pregnancy can also enhance the perception of these internal sounds. Fluid retention, which is common, can cause subtle swelling around the ear or affect pressure within the Eustachian tube. This may create a temporary feeling of fullness or mild conductive hearing loss, which inadvertently blocks out external ambient noise. When outside sounds are muffled, the body becomes more aware of its own internal noises, including the louder blood flow.
When to Consult a Healthcare Provider
While pulsatile tinnitus in pregnancy is frequently a physiological symptom, it is important to discuss its occurrence with a healthcare provider. Reporting the symptom allows your provider to rule out any non-pregnancy-related causes and ensure proper monitoring. You should seek prompt medical evaluation if the sound is accompanied by “red flag” symptoms.
These signs include the new onset of dizziness, persistent headaches, or changes in vision. Immediate investigation is warranted if the sound is strictly unilateral (heard only in one ear) and constant, or if you experience sudden hearing loss. Pulsatile tinnitus can sometimes indicate gestational hypertension or preeclampsia, conditions that require close monitoring. A thorough medical assessment ensures any underlying issues are managed promptly for the safety of both mother and baby.