Pregnant individuals often notice changes in their baby’s movements based on their body position. Many report increased fetal activity specifically when lying on their right side. This article will explore the physiological reasons behind this phenomenon and provide helpful information regarding fetal movement and comfortable sleeping positions during pregnancy.
Why Movement Might Increase on Your Right Side
One reason involves maternal anatomy and circulation. The inferior vena cava (IVC), a large vein carrying deoxygenated blood back to the heart, runs along the right side of the spine. When a pregnant individual lies on their back, or sometimes even slightly on their right side, the growing uterus can compress this vein. This compression can reduce blood flow returning to the heart, which might lead to a subtle change in blood flow to the placenta or the baby, prompting the baby to shift or move more noticeably in response.
The baby’s position and the available space within the uterus play a role. As the mother shifts, the baby’s orientation inside the womb can change. Lying on the right side might create a slightly different uterine shape or provide an increase in space for the baby to extend its limbs, making movements more apparent to the mother. The baby might also be more active during certain times of the day, with activity often peaking between 9 AM and 2 PM, and 7 PM to 4 AM, so changes in maternal position can coincide with these natural activity cycles.
Another possibility relates to slight nerve compression or changes in maternal comfort. Any shift in the mother’s body that alters nerve pathways or comfort levels could elicit a response from the baby. Fetal movements are a normal part of development, and their patterns can vary based on many factors, including the baby’s sleep-wake cycles.
Is This Normal?
Experiencing more fetal movement when lying on one side, including the right, is a normal variation and not a cause for concern. Fetal activity naturally changes throughout pregnancy, with movements becoming stronger and more vigorous as the baby grows, especially in the third trimester. Many pregnant individuals report feeling their baby move more frequently after 37 weeks.
The primary concern regarding fetal movement is a noticeable decrease in overall activity or a significant change from the baby’s usual pattern, regardless of the mother’s position. If you notice a reduction in movement, contact a healthcare provider immediately. Increased movement is not a sign of distress and has been associated with positive outcomes, such as higher birth weight.
Safe and Comfortable Sleeping Positions
Sleeping on the left side is generally recommended during pregnancy. This position optimizes blood flow to the uterus and the baby by reducing pressure on the inferior vena cava. Lying on the left side helps prevent the uterus from compressing this major blood vessel, ensuring efficient circulation.
To enhance comfort and maintain a side-sleeping position, using pregnancy pillows or regular pillows is beneficial. Placing a pillow under your belly, behind your back, or between your knees provides support and alleviate discomfort. While left-side sleeping is encouraged, it is normal to shift positions during sleep and wake up on your back or right side. The goal is to start on your side and use props to support yourself, rather than worrying about every minor shift during the night.