During your last prenatal visit, this is one of the things the doctor or midwife is looking for first: how does your baby, head or butt first appear? In the second case, it is a seat. We take stock.
Instinctively, the fetus settles in the most comfortable way. As soon as he feels that his head has become the most voluminous part of his individual, he lodges it in the most spacious space of yours: the bottom of your uterus, at the entrance of the neck. What he does not know when taking his quarters at the end of pregnancy is that he facilitates his delivery, the weight of his brain leading him to the exit ... But some babies refuse to do the pear and stay " sit "on their seat?
Why does he come to headquarters?
It is usually the head of the fetus who, becoming heavy, invites him to ... tumble! But it happens that this reversal is hindered by physiological causes:
- During a first pregnancy, the uterus is tonic. Sometimes, he has so little distended that the baby has difficulties ... insurmountable to turn around.
- Conversely, after several pregnancies, if the uterus has distended a lot, the fetus, approaching the term can move without problem, is more comfortable tailoring.
- It also happens that a malformation of the uterus or a placenta inserted too low prevents the rotation of the fetus.
- Other cases: an umbilical cord too short, an insufficient amount of amniotic fluid reduce its chances of moving.
When is this siege position irreversible?
- Before the 8th month, nothing is played: one in two babies would keep their nose up until the 32nd week. The doctor waits for this period to decide on the position of your baby that he perceives by simply palpating your belly.
- If he finds a seat, he will order an ultrasound to confirm his diagnosis. If your baby is truly seated, the doctor may try to tilt it by exerting pressure on your abdomen with your hands. The baby responds with a reflex: he pushes on his feet, thus helping to "maneuver". This "version" is done under ultrasound control during the 36th week. Twice in three, this attempt is successful.
Are all seats the same?
There are two types of seats:
- Uncompleted seats: they are the most numerous. The baby's legs are along his body, his feet reaching the level of the face. These are her buttocks that will appear first to the vulva.
- Full seats: the baby is sitting bent legs in front of him. When crossing your pond, he will unfold his legs and present his feet. This delivery is more delicate than that of an uncompleted seat, because elbows or chin can be retained in the excavation.
How to give birth to a seat?
- Before deciding between natural birth or cesarean section, the doctor takes your measurements ... that of your pelvis using a radiopelvimetry and those of your baby calculated during the ultrasound confirming the seat. It is on this ultrasound that he also checks that the head of your baby is well bent: raised, it might catch on the pelvis during the expulsion. With these data, the obstetrician can make his decision before birth.
- Caesarean section is needed if your pelvis is too narrow or if your baby is premature.
- Low birth under epidural is attempted, in principle, in other cases. It will simply be longer than during a presentation by the head, for various reasons:
- - buttocks softer than the skull, arriving first, exert less pressure on the cervix, the dilation is less well;
- - the body's dynamics of the baby is not the same: the different parts of his body do not necessarily pass together the different "doors" of your pelvis, some arm or chin release maneuvers may be necessary .
- They require expert hands and a great vigilance, that's why you will have around you, in the birth room, the whole obstetrical team: the obstetrician, the midwife, the anesthetist and the pediatrician ... perfectly honed at this childbirth.