Breech baby is the longitudinal location of the fetus in the uterus with legs or buttocks facing the entrance to the pelvis. Pregnancy with breech baby often occurs under the threat of termination, gestosis, fetoplacental insufficiency, fetal hypoxia, birth trauma. Diagnosis is performed using external and vaginal examination, echography, Dopplerography, CTG. Treatment of pelvic presentation includes complexes of corrective gymnastics, preventive external rotation of the fetus, early selection of the method of delivery.
Breech baby in obstetrics and gynecology occurs in 3-5% of all pregnancies. The management of pregnancy and childbirth with breech baby requires qualified and highly professional assistance to the woman and child. With breech baby during childbirth, the buttocks or legs of the child are the first to pass through the birth canal. At the same time, the cervix is still in an insufficiently smoothed and open state, therefore, the advancement of the head, as the largest and densest part of the fetus, is difficult. With pelvic presentation, childbirth can proceed uncomplicated, but there is an increased risk of asphyxia, stillbirth, birth injuries of the child and mother.
Variants of breech baby include leg and buttock presentations. The share of leg presentation accounts for 11-13% of cases of all breech baby. Leg presentation can be complete (both legs), incomplete (one leg) or knee (fetal knees). Gluteal presentation is most common. In 63-75% of cases, incomplete (purely gluteal) presentation is diagnosed, in which only the buttocks are attached to the entrance to the pelvis, and the legs of the fetus are elongated along the trunk. With mixed breech presentation (20-24%), not only the buttocks, but also the legs of the fetus bent at the knee or hip joints are turned to the entrance to the pelvis.
With different variants of breech baby, the development of the biomechanism of childbirth has its own characteristics. With a purely gluteal presentation, a medium-sized fetus and the normal size of the mother’s pelvis, uncomplicated independent childbirth is possible. With foot and mixed presentation, childbirth through the natural birth canal is associated with significant risks for the newborn – asphyxia, loss of the umbilical cord and individual parts of the fetus.
Causes of breech baby
The factors that determine the breech baby are numerous and have not been fully studied. The presence of uterine fibroids, ovarian tumors, anatomical narrowing or irregular shape of the pelvis, abnormalities of the uterine structure (intrauterine septum, hypoplasia, bicornular or saddle uterus) can prevent the establishment of the head to the entrance to the pelvis.
Pelvic presentation can be observed with increased fetal mobility caused by polyhydramnios, hypotrophy or prematurity, hypoxia, microcephaly, anencephaly, hydrocephalus and other factors associated with the pathology of the child. On the other hand, the limited mobility of the fetus in the uterine cavity with little water, a short umbilical cord or its entanglement also contributes to the formation of incorrect presentation.
The obstetric and gynecological history of the mother, burdened by repeated curettage of the uterus, endometritis, cervicitis, multiple pregnancies, abortions, complicated childbirth, can lead to breech baby. These conditions often lead to the development of pathological hypertonicity of the lower segments of the uterus, in which the head tends to occupy a position in the upper, less spasmodic parts of the uterine cavity. A change in the tone of the myometrium can also be caused by a scar on the uterus, neurocirculatory dystonia, neurosis, fatigue of a pregnant woman, stress, etc. This pathology is often combined with a low location or placenta previa.
In numerous observations conducted by obstetrics and gynecology, it is noted that breech baby develops in those women who themselves were born in a similar situation, therefore, the question of hereditary conditionality of leg and buttock presentation is considered.
Features of the course of pregnancy
With breech baby, the course of pregnancy, much more often than with the head, is associated with a threat or spontaneous interruption, the development of gestosis and fetoplacental insufficiency. These conditions, in turn, negatively affect the maturation of the nervous, endocrine and other systems of the fetus. With pelvic presentation in the fetus from 33-36 weeks of gestation, the maturation of the structures of the medulla oblongata slows down, which is accompanied by pericellular and perivascular edema. At the same time, the neurosecretory cells of the fetal pituitary gland begin to work with increased activity, leading to premature depletion of the function of the adrenal cortical layer, a decrease in the protective and adaptive reactions of the fetus.
Changes in the fetal sex glands are represented by hemodynamic disorders (venous stasis, small–point hemorrhages, tissue edema), which may later manifest itself as gonadal pathology – hypogonadism, ovarian depletion syndrome, oligo- or azoospermia, etc. With pelvic presentation, the frequency of congenital heart defects, central nervous system, gastrointestinal tract, musculoskeletal system in the fetus increases. Disorders of uteroplacental blood flow are manifested by hypoxia, high heart rate, decreased fetal motor activity. During childbirth, with breech baby, discoordinated or weak labor activity often develops. The most severe changes are observed in cases of mixed buttock or leg presentation.
Stable breech baby should be discussed after 34-35 weeks of gestation. Before this period, the location of the adjacent part may be changeable. Breech baby is determined by conducting external obstetric and vaginal examinations.
Breech baby is characterized by a higher standing of the uterine floor, which does not correspond to the gestation period. Methods of external examination allow to determine in the area of the womb a soft, irregular, sedentary part of the fetus that is not capable of running. In the area of the uterine fundus, on the contrary, it is possible to palpate a large, rounded, hard and mobile part – the fetal head. The heartbeat is heard above or at the navel level.
During internal gynecological examination, in the case of a purely gluteal presentation, a voluminous soft part is felt, in which the sacrum, coccyx, and inguinal fold can be distinguished. With a foot or mixed breech presentation, it is possible to distinguish the fetal feet with heel bumps and short fingers.
The position and its appearance during pelvic presentation are determined by the location of the dorsum, sacrum and interbody line of the fetus. The breech presentation of the fetus must be distinguished from such variants of the head presentation as facial and frontal. Clarification of the data regarding the breech baby is carried out using ultrasound, in particular, three-dimensional echography. The functional state of the fetus is assessed by Dopplerography of uteroplacental blood flow and cardiotocography.
Management of pregnancy and childbirth
In patients belonging to high-risk groups for the formation of pelvic presentation, measures are taken during pregnancy to prevent fetoplacental insufficiency, disorders of contractile activity of the uterus, fetal complications. Pregnant women are recommended to observe a gentle regime with a full night’s sleep and daytime rest, a balanced diet for the prevention of fetal hypertrophy.
Psychoprophylactic work is carried out with pregnant women, aimed at teaching methods of muscle relaxation and relieving nervous excitability. From the 35th week of gestation, corrective gymnastics is prescribed according to Dikan, Grishchenko and Shuleshova, Kayo, which contributes to a change in the tone of the myometrium and abdominal wall muscles, the transfer of the fetus from pelvic presentation to the head. In some cases, antispasmodic drugs are prescribed in intermittent courses.
Carrying out an external preventive rotation of the fetus on the head according to Arkhangelsk in some cases turns out to be ineffective and even dangerous. The risks of such obstetric admission can be the onset of premature placental abruption, rupture of the fetal membranes, premature birth, rupture of the uterus, injuries and acute fetal hypoxia. These circumstances in recent years have limited the use of external obstetric aids in the practice of treating breech baby.
A pregnant woman with a breech baby at 38-39 weeks of gestation is hospitalized in an obstetric hospital for planning the tactics of childbirth. With an uncomplicated obstetric situation (satisfactory condition of the fetus and the woman in labor, proportionality of the pelvis and fetus, biological readiness of the maternal organism, purely breech presentation, etc.), childbirth through the natural birth canal is possible. At the same time, prevention of premature opening of the fetal bladder, constant CTG monitoring of the fetus and uterine contractions, drug prevention of labor anomalies and fetal hypoxia, anesthesia (epidural anesthesia during childbirth), obstetric care for the speedy birth of the head is carried out.
Cesarean section with breech baby is planned with a burdened obstetric history of the mother (prolonged infertility, stillbirth, gestosis, postponed pregnancy, rhesus conflict, habitual miscarriage), the age of the primiparous over 30 years, the onset of this pregnancy due to IVF, large fetus, placenta previa, scar on the uterus, etc. testimony. Emergency caesarean section is also indicated in case of non-standard situations during independent childbirth.
In children born in pelvic presentation, intracranial injuries, encephalopathy, spinal injuries, hip dysplasia are often determined. If fetal asphyxia or aspiration of amniotic fluid is detected, appropriate resuscitation measures are required. Newborns in the early neonatal period are subject to a thorough examination by a neurologist. Birth injuries typical for breech baby in women include ruptures of the perineum, cervix, vagina and vulva, damage to the pelvic bones.
The preventive direction provides for a thorough examination and correction of disorders in women planning pregnancy; identification of pregnant risk groups for the development of breech baby and timely and adequate preparation for childbirth; early choice of delivery tactics and their management under the continuous supervision of an obstetrician-gynecologist.