During the ninth month of pregnancy (weeks 33-36) the uterus becomes very sensitive to the jolts and movements of your baby, who is now diligently “warming up” for their journey during labour. Your uterus muscles may periodically strain. Do not be scared! This is just the uterus doing “gymnastics”, as a kind of “rehearsal” for future births.
At the 33rd week, your baby’s weight is about 1800–1900 g, and the body length is around 43–44 cm.
The amount of subcutaneous fat increases, thanks to which the folds and wrinkles on the body of the baby are becoming smoother. The skin also turns pink. The fluff hairs covering the body of the fetus, which are called lanugo, lessens, and the hair on the head darkens and thickens. The skin of your baby is covered with a thin layer of cheese-like lubricant, mostly found in the folds and also on the back of the body and face. Its function is to protect the baby’s skin from damage and facilitate its passage through the birth canal.
By this time, the movement of the fetus gradually changes its usual character: it becomes more limited and less pronounced due to insufficient space. However, the strength of the movements is increasing, because by this time the fetal muscular system has already sufficiently strengthened. Sharp and strong jabs by your little one can be felt especially sensitively by your internal organs.
The height of the bottom of the uterus from the level of the pubis at this period is 34 cm. Many of your previously simple exercises, such as squatting or bending over, may feel limited due to your growing belly.
Due to a change in gravity, you may often find that your spine gets a lot of load on it. This can manifest itself as pain in the lower back, sacrum, and pelvic area. Also, the pressure of the uterus on the stomach can either cause nausea, heartburn, or a feeling of heaviness. In order to relieve these feelings, frequent meals in small portions are recommended.
An increase of almost 1 liter of circulating blood volume in a pregnant woman’s body increases the pressure on the kidneys, and the growing uterus can also press down on the bladder. This can manifest as a frequent need to go to the bathroom.
By the 34th week of your pregnancy, the weight of your baby is approximately 2100 g, and the height is around 45 cm.
The appearance of your little one is now almost indistinguishable from that of a newborn. Their body has become more proportional, and the face has lost its wrinkles and folds. Additionaly, the cheeks are becoming much more pronounced, thanks to the sucking reflex that your baby has developed, frequently sucking their thumb. This helps your child strengthen the muscles in their cheek. The overall muscle mass of your baby increases and the bones become heavier.
Also, during the day, your baby repeatedly swallows portions of amniotic fluid.
Most women begin to, rather intensely, experience false contractions in this very period, which are also called Braxton-Hicks contractions. These are episodic contractions of the uterus muscles, lasting from a few seconds to 3-5 minutes. Braxton-Hicks contractions are not pathological – this is a completely normal process of preparing the muscles of the uterus for the difficult process of labor.
The length of your baby is now about 46–47 cm, and their weight – 2200–2300 g. These figures in the last weeks of pregnancy can vary greatly, since growth and weight largely depends on heredity, individual parameters, and growth spurts of individual limbs. Starting from 35 weeks, your baby will be gaining around 200–250 g per week. Your littel one now occupies almost the entire space of your uterus: their back is rounded, and the arms and legs are bent and brought to the torso. The layer of subcutaneous fat increases substantially, which significantly “rounds” the body of your baby. The closing of the eyelids and the reduction of facial muscles changes the expression of the baby’s face quite often. The skin of the body becomes pink, smooth, and the amount of cheese-like lubricant on their body begins to decrease. Fluff hair covers separate small areas of the body, such as the shoulders and back. Nails form on the fingertips.
As for the future mother’s body: the bottom of the uterus from the pubis is now 35 cm high, from the navel 15 cm.
The growing uterus does not allow the lungs to be straightened, making respiratory movements limited and breathing difficult. Almost all pregnant women in one degree or another experience a feeling of shortness of breath – a feeling of lack of air, frequent and shallow breathing, and a desire to take a deep breath. As a rule, these sensations occur over a period of 28 weeks and reach their peak at the 35th – 36th week. After 37 weeks of pregnancy, abdominal prolapse occurs, which greatly helps bring easier breathing.
If shortness of breath is accompanied by blueing of the lips or nails, sensations of pain behind the sternum, darkening of the eyes, nausea or vomiting, or fainting, then you should immediately consult a doctor.
The growth of your baby by this time is approximately 47–48 cm, and its weight is 2300–2500 g. Your little one is now entering a period of intensive preparation for childbirth. Each of the organs is already functionally mature enough to ensure the viability of the fetus.
By the time of 36 weeks, the fetus occupies the final position in the uterus. As a rule, this is a longitudinal position, with your baby’s head down, and facing the back of the mother. This is the most comfortable position, ensuring the greatest safety of the baby in labor. More rarely, the buttocks and legs of the fetus are positioned down.
Changing the position of the fetus in the uterus is possible, but this happens infrequently, since during this period your baby will be occupying almost all the free space in the uterus, which significantly limits its physical activity. As a rule, if a change in the position of the fetus occurs, then it is only moving them upside down from the pelvic to the head. Reverse cases – the transition of the baby from the head position to the pelvic – is almost impossible, because the head of the fetus is heavier than the buttocks and occupies a longitudinal position completely. Usually, a decision can be made to deliver the baby through a cesarian section, but this depends on each individual case.
As for the mother, the height of your uterus from the pelvic floor is now 36 cm, and the volume of your abdomen is maximally enlarged.
During this time, the pregnant woman’s body also begins its journey of preparing for the upcoming delivery. Changes begin with hormonal adjustment: the woman’s level of special hormones, oxytocin and prostaglandins, somewhat increases. These active substances play a crucial role in the preparation and directly during your childbirth. A slight increase in their level from 36–37 weeks of pregnancy leads to increased Braxton-Hicks contractions, increased urination and bowel movements, and the appearance of more abundant mucous vaginal discharge.