We are already fully in the fetal periodAll of our baby's organs and structures will continue to grow and mature until the end of the pregnancy. It's a phase in which many women begin to feel more energetic, and although the bump may not yet be very noticeable, the body is already undergoing very evident internal changes.
What does my baby look like at 16 weeks pregnant?
At this stage there are already coordinated movements in your legsand little by little also in your arms. The baby can flex the limbsOpen and close your hands and begin to develop the grasp reflex, which allows it to grab its feet, its own hands and even the umbilical cord.
A 16-week-old fetus typically measures approximately between 11 and 13 centimeters and sorrow surrounding 80-100 gramsIt is very similar in size to an avocado. head and body They begin to be more proportionate: the head is no longer so large in relation to the rest of the body, and the limbs lengthen and become better defined.
In ultrasound measurements, one can assess, for example, the biparietal diameter of the head (around 33 mm) and the femur length (approximately 21 mm). These parameters help to verify that fetal growth is adequate for gestational age.
The baby's skin appears fluffThat very fine, soft hair that covers the entire body and helps protect the skin inside the amniotic fluid. The... scalp hair patternAlthough it will still change a lot before birth. Furthermore, the fingernails and toenails and they develop epidermal folds in the palms and fingers, so the baby already has own fingerprints.
This week the position of the eyes and earsThe eyes appear more centered on the face, and the ears rise to their almost final position. The eyelids remain closed, but the baby is already making movements. slow eye movements and begins to move your eyes pacing back and forth, preparing for extrauterine vision.
The skeleton of our baby begins a process called ossification. This process consists of the actual formation of bone.Up to this point, the baby's skeleton is made up primarily of cartilage, and through a series of processes, these cells transform into the typical structure of bone. This is the moment when the baby begins to... absorb a large amount of calcium to harden your bonesTherefore, it is especially important that the mother maintain a diet rich in calcium and vitamin D.
Furthermore, around week 16, the following begin to develop more intensely: bones of the ear and back muscles They gain volume and strength. This allows the baby to... hold your head up better and increase your capacity to responding to stimuliAlthough he doesn't yet hear like a newborn, he is beginning to have a sensory capacity older and is getting ready to recognize sounds and vibrations.
El circulatory system It's already functioning and the heart is pumping the baby's own blood. Around this stage, the hematopoiesis, the process by which the elements of the blood (red blood cells, white blood cells, platelets, etc.) are formed and mature.
In girls, the ovaries finish differentiating.In week 16, we find cells in the ovary that will become oocytes, from which eggs will be released throughout her fertile life, and which are currently in the process of formation. It's interesting to know that Women are born with the number of oocytes they will have throughout their fertile life.In children, however, the testicle has differentiated much earlierbut it will not begin producing sperm until puberty.
During the fetal period we find four stages of growth depending on the baby's weight gain. Week 16 marks the beginning of the next stage. Accelerated growth, in which our baby will gain approximately 85 grams per week, practically doubling its weight and size in the coming weeks.
The placenta is already working at full capacity, producing the hormones necessary for the development of our baby and the maintenance of pregnancyIn addition, it acts as a true filter that allows oxygen and nutrients to pass to the fetus and eliminates waste products.
Symptoms in the mother at 16 weeks
Usually The nausea has now disappeared and a calmer period begins In that sense. They tend to persist feeling of fullness after eating, as well as the constipationThis is due both to the action of hormones and the pressure of the uterus on the intestines. Most likely the discomfort in the lower abdomen They have practically disappeared, although you may notice some tightness due to the stretching of the ligaments.
El size of the uterus It increases noticeably, and its highest point can be felt between the pubic bone and the navel. This can cause a sensation of hardness in the lower abdomen and little side punctures This can happen when you stretch or change position. It's usually due to the uterine ligaments adapting and generally doesn't indicate anything serious.
You will continue to sleep in a somewhat peculiar way. You don't sleep badly, you sleep like a pregnant woman.Three or four hours at the beginning of the night, and after getting up several times to go to the bathroom, you sleep in short bursts. Many women find that Sleeping on your side, especially on your left sideLying down with a pillow between your knees and another under your abdomen greatly improves rest and circulation.
It is common to notice increased appetitebecause the baby is more developed and requires a greater energy intake. It can also increase breast volume and sensitivity, as well as the appearance of swollen or bleeding gumsTherefore, it is advisable to be extra careful with oral hygiene. Pathologies such as caries dental and oral sepsis They are more common during pregnancy, and many health centers have specific oral health check-up programs for pregnant women.
Other symptoms may appear or persist at this stage, such as backache, sensation of tired legs, varicose veins or nighttime cramps. The practice of moderate exercise Walking, swimming, and prenatal yoga can help improve circulation, reduce lower back pain, and control weight gain. It's always advisable to consult with your healthcare provider before starting any exercise program.
Generally, We started to feel better and less worriedWe begin to enjoy the pregnancy, with more energy and a better mood. Some women even talk about the “special glow of pregnancy", since the increased blood flow and skin fat can give the skin a rosier and brighter appearance, although spots (melasma) or small acne breakouts may also appear."
Although the baby moves a lot, it's too early to notice the movements clearly.They'll probably tell you that you should be feeling them by now, but don't listen: the fetus is still small and, especially in a first pregnancy, the first movements can feel like bubbles, gases, or butterfly flapping and they usually appear between weeks 16 and 20.
Tests and checks in week 16
At this point We will already have the final result of the triple screening and the fetal DNA test If we've had it done. Thanks to these tests, the possible risk of the baby having any [conditions] can be estimated. chromosomal alterationBased on the results and the medical history, the specialist will assess whether further tests are necessary.
Between weeks 16 and 18 it is common to offer a second trimester screening or multiple marker test. It usually includes the determination of the alpha-fetoprotein (AFP) and of various pregnancy hormones in maternal blood. Although its use has been reduced in some protocols due to the number of false positives, it remains a tool that, combined with other data, provides guidance on the risk of neural tube defects o chromosomal syndromesIt's always important to discuss the following with the professional. benefits and limitations of each test.
If it hasn't been done before, it can also be considered a screening for asymptomatic bacteriuriaUrinary tract infections are more common during pregnancy, often without clear symptoms. Detecting and treating them early reduces the risk of complications.
Many women take advantage of this period to get a procedure. additional ultrasound, sometimes in private centers, in order to learn about baby gender If the fetal position allows it. From week 16 onwards, the external male or female genitalia can generally be visualized quite well, although sometimes it is necessary to wait a little longer to confirm it.
Amniocentesis
It is an invasive test which is reserved for cases in which the risk of chromosomal or genetic alteration is relevant, or when advised by the results of previous screenings or family history.
It is done for remove a small amount of amniotic fluidThen, the fetal cells and their DNA is analyzed. The baby's karyotype is performed and chromosomal abnormalities are ruled out. in the number or shape of the chromosomes. The test also allows one to know with certainty the baby gender.
Before performing the procedure, they will perform an ultrasound to locate the placenta, the baby and the umbilical cordThe test is performed with continuous ultrasound monitoring to choose the safest puncture point. They perform a puncture in the abdomen until they reach the amniotic sac; It's important to be very still. to facilitate the procedure.
Although final results take a couple of weeksIn 48 or 72 hours, a first approximation of the result is usually available using faster techniques. Amniocentesis primarily rules out abnormalities in the number and shape of chromosomes.although in specific cases it can also study some specific genetic diseases.
After the test, it is important to have rest for two or three daysIt is recommended to avoid physical exertion, lifting heavy objects, or intense exercise. If you experience any symptoms such as fever, vaginal bleeding, fluid loss, or severe abdominal pain, you should go to the emergency room for evaluation.
Alongside these tests, a routine pregnancy check-up with blood pressure measurement, weight control, blood and urine tests, and review of any symptoms that may appear.
At this stage of pregnancy, the percentage of pregnancies that are considered high risk It is relatively low, but when there are additional factors (hypertension, diabetes, multiple pregnancies, history of complications, etc.) a closer and more individualized monitoringwith more frequent visits and ultrasounds to care for the health of the mother and baby.
The end of this stage of the second trimester is often experienced as a very special time: the pregnancy becomes more visible, the baby gains weight and movement, and the mother usually feels better both physically and emotionally. Enjoying this stage, following recommendations for diet, exercise, and medical checkups, and addressing any questions with your healthcare provider helps you experience week 16 with greater peace of mind and confidence.