One of the most exciting parts of pregnancy begins! Your baby is rapidly growing and your stomach is too! Soon you will feel their first movements. We’ve outlined how things develop, and everything else you can expect in this review.
Rapid weight gain
From the second trimester on, you will likely gain an average of 300-500 grams per week [1]. The extra weight consists of the weight of the baby, the uterus, and the amniotic fluid. In addition, the volume of circulating blood in your body increases, and by the end of pregnancy, it will be up to one and a half liters more than at the beginning.
The belly is growing
The uterus has grown to the size of a grapefruit and no longer fits in the pelvic cavity, so your lower abdomen begins to round out [2]. By the middle of the trimester, your uterus will grow to the level of your navel and your pregnancy will become noticeable to others. By the end of the trimester, the baby will occupy most of the abdominal cavity and begin to prop up the chest [3]. Then your belly will start growing forward.
The baby starts to move
Your baby has actually been waving their arms and legs since the eighth week [4]. But it’s not until weeks 18 to 20 that they are big enough for you to feel their movements [5]. At first, the movements will feel light and occasional, more like a bubbling in the stomach. But by the end of the trimester, you will become an expert on your baby’s movements! You will learn to distinguish kicks from somersaults and may find yourself interacting with them more and more.
Biological sex can be seen on ultrasound
By the beginning of the second trimester, a boy’s penis and a girl’s vulva are formed. In theory, the genitals can be seen on an ultrasound by week 14 [6]. In practice, most parents find out the sex of the child a month and a half later, during the second-trimester screening, and only if they wish to know, of course.
In recent years, many doctors have started offering genetic blood testing, which can identify the baby’s DNA in the mother’s blood, screening for different conditions and determining the baby’s sex [7].
A dark stripe appears on the abdomen
This is a well known characteristic of pregnancy, but may be more or less noticeable depending on your skin tone. Known as the linea nigra, this pigmented line appears from the pubic bone to the navel as a consequence of an increase in hormones and melanin. This extra pigmentation can accumulate in some areas, including the belly. The areolas around the nipples, the skin around the mouth and nose, and the inner thighs can also darken [8]. After childbirth, this pigmentation will disappear on its own.
New symptoms appear
The second trimester is usually considered the most enjoyable period of pregnancy. Nausea and drowsiness are left behind, and the challenges of the final weeks are relatively far ahead [9]. Still, you can expect to experience a few new symptoms. Here’s what most expectant mothers report during the second trimester:
Growing pains. They feel like a sharp spasm on one side of the abdomen and tend to subside when you change position. The pain is caused by the stretching of the muscles and ligaments, which are working to accommodate a rapidly growing uterus [10].
Stuffy nose. Under the influence of the hormone progesterone, the mucous membranes swell and it may become difficult to breathe. Ask your doctor to prescribe safe nasal drops and rinse your nose with saline solution if you need to [11].
Constipation. Hormonal changes can slow down digestion, hence the unpleasant irregularity common during pregnancy. The standard action [12].
