Pregnancy often brings unexpected physical changes, including the onset or worsening of snoring, known as gestational snoring. This phenomenon affects a significant portion of expectant individuals, with prevalence rates ranging widely from 14% to over 50%. While it can occur at any point, the frequency and intensity increase dramatically as pregnancy progresses, becoming most noticeable during the third trimester. Understanding the underlying physiological shifts explains these nightly sounds.
Hormonal and Fluid Changes
The primary physiological driver behind new-onset snoring is the alteration in hormonal landscape. Pregnancy causes a surge in hormones like estrogen and progesterone, which directly impact the tissues lining the respiratory tract. These hormones promote vasodilation (the widening of blood vessels) and increase blood flow to the mucous membranes in the nose and throat.
The increased blood supply contributes to swelling (edema) in these upper airway tissues, often called rhinitis of pregnancy. When the nasal and pharyngeal passages swell, the available space for air shrinks considerably. This narrowing forces inhaled air through a smaller opening, causing soft tissues to vibrate and produce the characteristic sound of snoring.
Congestion is compounded by the substantial increase in total body fluid and blood volume, which can rise by up to 50% during pregnancy. Generalized fluid retention affects all tissues, further contributing to the thickening of the upper respiratory tract lining. This combination of hormonal swelling and increased fluid retention is a major reason why the airway is less stable during sleep, leading to greater resistance and vibration.
Mechanical Effects on Airflow
Beyond internal biochemical changes, external physical factors related to the growing fetus and maternal body mass also mechanically affect airflow. Normal weight gain during pregnancy can result in increased soft tissue deposits around the neck and throat. This extra tissue mass physically compresses the airway, making it more prone to collapse during the deep relaxation of sleep.
As the uterus expands, particularly in later stages, it pushes the diaphragm upward toward the lungs. This shift changes breathing mechanics by reducing functional lung capacity and altering the resting position of the chest wall. Such changes influence the breathing pattern during sleep, which may exacerbate any existing tendency toward snoring.
The position chosen for sleep also plays a significant role in airway mechanics. Lying flat on the back (the supine position) allows gravity to pull the tongue and soft palate backward against the throat. This is unfavorable in late pregnancy, as the enlarged abdomen can compromise airway stability, often making snoring louder and more frequent.
When Snoring Signals a Greater Risk
While mild, occasional snoring is a common pregnancy symptom, severe or new-onset habitual snoring can signal a more serious underlying issue. Snoring accompanied by gasping, choking sounds, or noticeable pauses in breathing may indicate Obstructive Sleep Apnea (OSA). OSA is a condition where the airway repeatedly collapses completely during sleep, causing fragmented rest and drops in blood oxygen levels.
Research has established a statistically significant link between new-onset habitual snoring and an elevated risk for hypertensive disorders. Individuals who begin snoring frequently have double the risk of developing gestational hypertension and a higher risk for preeclampsia compared to non-snorers. This association is thought to be driven by the inflammatory response and intermittent hypoxia (low oxygen) caused by breathing disturbances.
The repeated oxygen deprivation and stress on the mother’s cardiovascular system can also have implications for the developing fetus. Severe sleep-disordered breathing, including OSA, is associated with a greater likelihood of adverse fetal outcomes, such as lower birth weight, fetal growth restriction, and preterm birth. If a person experiences severe daytime fatigue, morning headaches, or a sudden increase in snoring, consultation with a healthcare provider for screening is warranted.
Management and Relief Strategies
Several non-medical approaches can help mitigate the effects of gestational snoring and improve sleep quality. A fundamental strategy involves changing the sleeping posture to favor side sleeping, particularly on the left side. This position helps keep the airway open by preventing the tongue and soft tissues from collapsing backward, and it promotes optimal blood flow.
Addressing nasal congestion caused by hormonal swelling can provide relief. Using over-the-counter saline sprays or rinses helps moisturize and clear the nasal passages without medication. External nasal dilator strips, which physically lift and open the nostrils, can be placed across the bridge of the nose to improve airflow.
Elevating the head of the bed by a few inches, rather than just propping the head with pillows, can use gravity to further prevent airway obstruction. Maintaining a healthy and recommended rate of weight gain, as advised by a doctor, also helps minimize the amount of extra tissue around the throat. Using a humidifier in the bedroom can reduce dryness and irritation of the nasal membranes, making breathing easier.