The fourth month of pregnancy marks an exciting time as your baby continues to grow and develop rapidly. This period, which typically spans weeks 13-16 of pregnancy, brings significant changes for both the developing fetus and the expectant mother. Understanding these changes can help you better prepare for this important stage of pregnancy.
Fetal Size and Weight at 4 Months
At 4 months, your developing baby has reached several important growth milestones. The fetus typically measures between 4 to 5 inches in length (about the size of a large pear) and weighs approximately 2.5 to 3.5 ounces. This represents a dramatic increase from earlier stages of pregnancy, showcasing the rapid development taking place.
Physical Development and Features
During the fourth month, your baby's physical features become increasingly defined and recognizable. The facial features are more distinct, with the formation of eyebrows and eyelashes. The ears have moved to their final position on the sides of the head, and the eyes, though still closed, have moved from the sides to the front of the face.
Key Developmental Milestones
- External genitalia becoming more defined
- Skeletal system continuing to harden
- Skin beginning to develop, though still transparent
- Hair starting to grow on the head
- Digestive system beginning to function
Fetal Movements and Activity
The fourth month marks an exciting transition as your baby becomes increasingly active. While they've been moving for weeks, you might start feeling these movements for the first time. These initial sensations often feel like subtle flutters, sometimes described as "quickening," though not all pregnant people will feel movement this early.
Gender Determination
Around the fourth month, many parents have the opportunity to learn their baby's biological sex during an ultrasound examination. While gender determination at this stage can be quite accurate (around 90-95% accurate), the clarity of the ultrasound image and the position of the baby can affect the healthcare provider's ability to make a definitive determination.
Maternal Changes and Symptoms
The fourth month often brings welcome relief from early pregnancy symptoms, but new changes emerge. Common experiences include:
- Visible belly growth
- Decreased nausea and fatigue
- Increased appetite
- Nasal congestion
- Round ligament pain
- Skin changes and potential darkening of the linea nigra
Frequently Asked Questions
How big and how much does a 4-month-old fetus typically weigh and measure?
A 4-month-old fetus typically measures 4 to 5 inches in length and weighs between 2.5 to 3.5 ounces. This is approximately the size of a large pear.
What physical features and movements can a fetus have at 4 months of pregnancy?
At 4 months, the fetus has developed distinct facial features, including eyebrows and eyelashes. They can make various movements, including sucking motions, and their skeletal system is hardening. The skin is still somewhat transparent, and hair is beginning to grow.
Can the gender of the fetus be determined at 4 months, and how accurate is it?
Yes, gender can typically be determined through ultrasound at 4 months with approximately 90-95% accuracy, depending on the baby's position and image clarity during the examination.
When can a pregnant person start to feel fetal movements around 4 months?
Some pregnant people begin feeling fetal movements, known as "quickening," around 4 months. These initial movements often feel like subtle flutters, though it's normal not to feel movement until later in pregnancy.
What are common maternal symptoms and changes in the body at 4 months pregnant?
Common symptoms at 4 months include visible belly growth, decreased morning sickness, increased appetite, nasal congestion, round ligament pain, and skin changes. Many people experience an improvement in early pregnancy symptoms during this time.
