Hormonal changes can also contribute, especially as people age. Shifts in melatonin production, menopause, thyroid imbalance, or irregular cortisol rhythms may affect sleep continuity. Certain medications, including those for blood pressure, depression, or asthma, are also known to interfere with nighttime rest.
Occasional early waking is usually harmless and may simply reflect temporary stress, fatigue, or lifestyle changes. However, if waking at 3 or 4 a.m. becomes frequent and is accompanied by exhaustion, irritability, or trouble functioning during the day, it may indicate an underlying sleep disorder such as insomnia or circadian rhythm disturbance.
