Sleep during pregnancy is notoriously unpredictable — and for women who become pregnant after 35, a combination of age-related changes and pregnancy-specific factors can make rest feel particularly elusive. Understanding why sleep shifts during pregnancy, and what approaches some women find helpful, can offer useful context for navigating this experience.
This article focuses on sleep changes across the trimesters of pregnancy, drawing on research from reproductive health and sleep medicine. The aim is to provide accurate, balanced information — not to prescribe solutions, since individual sleep experiences during pregnancy vary enormously.
Why Pregnancy Changes Sleep Architecture
Pregnancy involves dramatic hormonal, physical, and metabolic changes that collectively affect virtually every body system — including sleep. According to research published through the National Institutes of Health, sleep disturbances affect an estimated 78% of pregnant women, making them one of the most common pregnancy experiences.
The primary drivers of sleep changes during pregnancy include hormonal fluctuations — particularly rising progesterone in the first trimester — physical discomfort, frequent urination, and emotional factors including anticipatory anxiety. For women over 35, there is sometimes an additional layer of anxiety in early pregnancy that may compound sleep disruption.
First Trimester: Drowsiness and Disruption
Many women find the first trimester paradoxically tiring — feeling sleepy throughout the day while also experiencing disrupted night-time sleep. Surging progesterone levels are thought to contribute to daytime sleepiness, while frequent urination, nausea, and heightened anxiety may interfere with sustained nighttime rest.
For more context on how progesterone specifically affects sleep, the article on progesterone and sleep after 35 may offer helpful background. Sleep position becomes a topic of discussion during pregnancy, though first-trimester position concerns are less pressing given the smaller uterine size.
Second Trimester: Some Improvement, New Challenges
The second trimester is often described as the most comfortable phase in terms of sleep, as nausea typically diminishes and energy levels often improve. However, sleep disruptions do not disappear entirely. As the abdomen grows, finding a comfortable sleeping position becomes progressively more challenging. Many providers suggest side-lying positions, and the use of supportive pregnancy pillows is something many women find helpful.
Restless Legs Syndrome During Pregnancy
Restless legs syndrome (RLS) — an uncomfortable urge to move the legs, particularly at night — is reported more frequently during pregnancy than in the general population. Research suggests it may be related to iron deficiency, folate levels, and hormonal changes. If you are experiencing RLS-like symptoms during pregnancy, discussing them with your OB/GYN is worthwhile.
Third Trimester: Sleep Becomes More Challenging
The third trimester typically brings the most significant sleep challenges. Physical factors — including fetal movement, shortness of breath, heartburn, hip and back discomfort, and increasing urinary frequency — can make both falling asleep and staying asleep difficult.
Sleep-disordered breathing, including snoring and in some cases obstructive sleep apnea, can also emerge or worsen during pregnancy. Research suggests that pregnancy-related sleep apnea may be more common than generally recognized. If you or your partner notice significant snoring, gasping, or pauses in breathing during sleep, mentioning this to your provider is important.
For broader context on navigating pregnancy after 35, exploring resources on what to expect during pregnancy after 35 may be helpful.
Approaches Some Women Find Helpful
A range of behavioral and positioning approaches may support sleep quality during pregnancy. These include establishing a consistent sleep and wake schedule where possible, using supportive pillows, keeping the bedroom cool and dark, limiting fluid intake close to bedtime while staying well-hydrated overall during the day, and addressing anxiety through relaxation techniques or speaking with a therapist. Any supplements or medications should be discussed with your OB/GYN or midwife before use during pregnancy.
Frequently Asked Questions
Is it safe to take sleep aids during pregnancy?
This is an important question to discuss directly with your OB/GYN or midwife. Even supplements often considered low-risk outside of pregnancy — such as melatonin — have not been extensively studied in pregnant populations. Your provider is best positioned to advise you on what may be appropriate for your specific situation.
Why am I so tired in the first trimester but can’t sleep well at night?
This paradox is common in early pregnancy and is thought to relate to the effects of rising progesterone combined with physical factors — including nausea, frequent urination, and emotional adjustment — that can interfere with sustained nighttime sleep. Most women find this pattern improves in the second trimester as hormone levels stabilize somewhat.
Is it harmful to sleep on my back during pregnancy?
Current evidence suggests that sleeping on the back in late pregnancy may affect blood flow through the inferior vena cava due to the weight of the uterus. Most providers suggest sleeping on your side — particularly the left side — as a general recommendation in the third trimester. Discuss your specific concerns with your provider.
Will my sleep improve after the first trimester?
For many women, the second trimester brings some improvement in sleep quality as early-pregnancy symptoms ease. Individual experiences vary, and third-trimester sleep is commonly described as the most disrupted, primarily due to physical factors.
Key Takeaways
- Sleep disturbances affect the majority of pregnant women and are driven by hormonal, physical, and emotional factors that evolve across the trimesters.
- The first trimester often brings paradoxical drowsiness alongside disrupted nighttime sleep; the second may offer some relief; the third typically presents the most physical challenges.
- Pregnancy-related sleep-disordered breathing can emerge or worsen during pregnancy and should be discussed with a provider if suspected.
- Behavioral and positioning approaches may help support sleep quality; any supplements or medications should be discussed with your provider before use during pregnancy.
- Individual experiences of sleep during pregnancy vary considerably — there is no single “normal.”
Medical Disclaimer
This content is for informational purposes only and does not constitute medical advice. Individual health situations vary significantly. Always consult a qualified healthcare provider before making decisions related to your health, fertility, or pregnancy.
About the Author
Emily Carter is a women’s health writer focused on fertility, pregnancy after 35, and sleep changes in midlife. She writes research-informed, non-alarmist content to help women navigate reproductive and hormonal transitions with clarity and confidence.