40 Weeks Pregnant: Baby Development, Symptoms & Signs | Week by Week

July 9, 2025 / Flourish Community Care

As the final week of pregnancy arrives, anticipation and excitement fill the air. Expectant parents are on the brink of welcoming their little one into the world. This week marks a significant milestone, as the baby is fully developed and ready for birth. In this article, we will explore your baby’s development, the changes happening in your body, common symptoms, and helpful tips to navigate this crucial week.

Your Baby’s Development at Week 40

Overview of Your Baby’s Growth

At 40 weeks, your baby has reached full term, typically weighing between 5.5 to 8.8 pounds and measuring around 18 to 22 inches long. The development that has taken place over the past nine months is nothing short of miraculous. Renowned pediatrician Dr. Benjamin Spock emphasized the importance of this period, stating that a baby at this stage is equipped with all the necessary skills to thrive outside the womb.

During this final week, the baby’s lungs are fully matured, and they have developed a layer of fat that helps regulate body temperature. The brain is also continuing to grow, forming connections that will support cognitive functions in the future.

40 Weeks: Month Conversion Explained

Pregnancy is often measured in weeks, but many expectant parents find it helpful to convert those weeks into months. At 40 weeks, you are at the end of the ninth month of pregnancy. This conversion can help provide a clearer picture of the timeline, as some may find it easier to think in terms of months rather than weeks.

To break it down: 40 weeks is approximately 9 months and 1 week. This understanding can help parents grasp how far along they are in the pregnancy journey.

Baby’s Size and Measurements

Measuring your baby’s growth can be an exciting aspect of pregnancy. At 40 weeks, the average baby is about the size of a small pumpkin. This size can vary significantly, with some babies being smaller or larger than average. The American College of Obstetricians and Gynecologists notes that the size of the baby can influence labor and delivery, making it essential to stay in touch with healthcare providers for personalized insights.

Transitioning at the End of Pregnancy

As the pregnancy draws to a close, both the baby and the mother undergo significant transitions. For the baby, the transition involves preparing for life outside the womb, including the ability to breathe air and regulate body temperature. For the mother, this transition often comes with a mix of emotions, from excitement to anxiety.

Experts like Dr. Harvey Karp, a pediatrician and child development expert, emphasize the importance of preparing both physically and emotionally for this transition. Engaging in relaxation techniques and discussing feelings with a partner or support group can be beneficial.

Preparing to Meet Your Baby

As the due date approaches, preparing for the arrival of your baby becomes a priority. This includes packing a hospital bag, setting up the nursery, and ensuring that you have everything needed for the first few days at home. Dr. Karp suggests creating a checklist to ensure nothing is overlooked, as it can help ease the stress of last-minute preparations.

Additionally, attending prenatal classes can provide valuable information and boost confidence for the upcoming labor and delivery experience.

Benefits of Swaddling for Newborns

Swaddling is an age-old practice that can have numerous benefits for newborns. It mimics the snug environment of the womb, providing comfort and security. Experts like Dr. William Sears advocate for swaddling, noting that it can help soothe fussy babies and promote better sleep patterns.

However, it’s essential to swaddle safely, ensuring that the baby’s hips can move freely to prevent hip dysplasia. Parents are encouraged to learn proper swaddling techniques to maximize the benefits.

Changes in Your Body at Week 40

Due Dates and Timing

Due dates can be a source of confusion and anxiety for many expectant parents. The estimated due date is typically calculated based on the first day of the last menstrual period, but it’s important to remember that only about 5% of babies are born on their due date. Renowned obstetrician Dr. Ina May Gaskin emphasizes that every pregnancy is unique, and it’s essential to be flexible and patient as the body prepares for labor.

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Understanding that labor can start anytime within a week or two before or after the due date can help ease some of the pressure surrounding this timeline.

Signs Your Water May Break

As labor approaches, many expectant mothers may wonder about the signs that indicate the water has broken. This can include a sudden gush of fluid or a slow leak. Dr. Gaskin advises that if there is any uncertainty, it’s best to contact a healthcare provider for guidance. Knowing when to head to the hospital is crucial for a smooth delivery.

Additionally, recognizing other signs of labor, such as regular contractions or back pain, can help in understanding when it’s time to seek medical attention.

Addressing Common Labor Anxieties

It’s natural to feel anxious as the due date approaches. Many expectant parents worry about the labor experience, potential complications, and the well-being of their baby. Experts in maternal mental health suggest that discussing these anxieties with a partner or healthcare provider can be incredibly beneficial.

Practicing relaxation techniques, such as deep breathing or visualization, can also help manage stress levels. Engaging in open conversations about fears and expectations can foster a supportive environment as the big day approaches.

Common Pregnancy Symptoms at Week 40

Physical Discomforts to Expect

As the body prepares for labor, many women experience various physical discomforts. Common symptoms include back pain, swelling in the feet and ankles, and increased fatigue. Dr. Spock notes that these discomforts can be attributed to the body’s adjustments as it gears up for delivery.

Staying active, within reason, and practicing gentle stretching can help alleviate some of these discomforts. Additionally, using pillows for support while sleeping can improve comfort levels during this final week.

Emotional Changes and Support

The emotional rollercoaster of pregnancy can intensify in the final week. Feelings of excitement, anxiety, and even sadness can arise as the reality of becoming a parent sets in. Experts like Dr. Laura Markham emphasize the importance of seeking support during this time, whether through friends, family, or professional counseling.

Engaging in mindfulness practices, such as meditation or journaling, can also help manage emotional fluctuations. It’s crucial to acknowledge these feelings and seek support when needed.

Helpful Tips for This Week

Preparing for Labor and Delivery

Preparation is key as the final week of pregnancy unfolds. Creating a birth plan can help clarify preferences regarding labor and delivery. Discussing this plan with healthcare providers ensures that everyone is on the same page, which can help reduce anxiety during labor.

Additionally, attending a hospital tour or childbirth class can familiarize parents with the environment and processes, making the experience less daunting.

Self-Care Strategies for New Parents

Self-care is essential for new parents, especially during the final days of pregnancy. Simple practices like taking warm baths, enjoying calming herbal teas, and indulging in light reading can provide moments of relaxation amidst the chaos of preparation.

Moreover, prioritizing sleep and nutrition can help maintain energy levels as the body prepares for the demands of labor and caring for a newborn. Remember, taking care of oneself is a crucial step in ensuring the well-being of both the parent and the baby.