Stillbirth is the death of the fetus during pregnancy. It can be provoked by somatic diseases, diseases and abnormalities of the reproductive system, infections, intoxications, abdominal injuries, rhesus conflict, multiple births, severe fetal birth defects and other factors. Stillbirth is manifested by the cessation of uterine growth, the absence of fetal movements and heartbeat, weakness, malaise, pain and heaviness in the lower abdomen. The diagnosis is established based on the results of the examination and the data of instrumental studies. Treatment in the first trimester – curettage, in the second and third trimesters – urgent delivery.
O36.4 Intrauterine fetal death requiring medical assistance to the mother
Stillbirth (intrauterine fetal death) is the death of the fetus during intrauterine development (before the onset of labor). It is the cause of 39% of stillbirths. Statistical data on the prevalence of this pathology vary significantly, due to the difference in the classifications of intrauterine deaths in different countries. In the UK, the perinatal mortality rate (including antenatal and intranatal mortality) is 0.58%, in the USA – 1% excluding miscarriages before 20-22 weeks of pregnancy. Stillbirth is provoked by various external and internal factors. It may pose a threat to the life and health of a pregnant woman. In the case of multiple pregnancies, it increases the likelihood of delayed development and death of the second fetus. Diagnosis and treatment are carried out by specialists in the field of obstetrics and gynecology.
This pathology can occur under the influence of various endogenous and exogenous factors. Endogenous factors causing stillbirth include:
- infectious diseases (influenza, pneumonia, measles, rubella, hepatitis);
- somatic diseases (congenital heart defects, cardiovascular insufficiency, severe liver and kidney diseases, anemia of various genesis);
- diabetes mellitus and other diseases of the mother’s endocrine system;
- gestosis (eclampsia, nephropathy);
- severe fetal abnormalities;
- rhesus conflict, blood group incompatibility;
- polyhydramnios, lack of water;
- disorders of placental circulation (with anomalies of placental attachment, placental abruption, fetoplacental insufficiency and arteriovenous anastomoses of the vessels of the common chorion in twins);
- umbilical cord abnormalities: true umbilical cord knot, umbilical cord entwining around the fetal neck;
- inflammatory diseases of the mother’s reproductive system.
Exogenous factors provoking stillbirth are toxic effects (smoking, alcoholism, drug addiction, substance abuse, taking certain medications, acute and chronic poisoning with household and industrial poisons), ionizing radiation and abdominal injuries.
According to research, the leading positions in the list of causes of this pathology are occupied by severe fetal malformations, pathology of the placenta, infections, injuries and intoxication. Sometimes the cause of stillbirth remains unclear.
After death, the fetus may remain in the uterus for several days, months, or even years. In this case, maceration, mummification or petrification is possible. 90% of fruits undergo maceration – wet necrosis resulting from contact with amniotic fluid. At first, tissue necrosis is aseptic in nature. Some time after the antenatal death of the fetus, necrotic tissues may become infected. Severe infectious complications, including sepsis, are possible.
The macerated fruit looks soft, flabby. In the early stages of maceration, the skin is reddish, covered with blisters alternating with areas of exfoliated epidermis. When an infection is attached, the fetus becomes greenish. The head and torso are deformed. An autopsy is performed to determine the cause of stillbirth. The autopsy reveals the impregnation of tissues with fluid and atelectasis of the lungs. Cartilage and bones are brown or reddish, the epiphyses are separated from the metaphyses. With prolonged stay in the uterus, autolysis of internal organs is possible. Sometimes, with a delay in the uterus, the fetus is soaked with blood, forming a blood drift, which subsequently transforms into a fleshy drift.
With multiple births and entanglement of the umbilical cord, the fetus is often mummified. It is squeezed by a living twin, shrinks in size, shrinks. Sometimes the mummified fetus subsequently undergoes petrification (“petrification” as a result of the deposition of calcium salts). Petrification is more often observed in ectopic pregnancy, although it can occur during normal gestation. A petrified fetus can stay in the uterus or in the abdominal cavity for years without causing any pathological symptoms.
Intrauterine fetal death is accompanied by the cessation of uterine growth. Fetal movements disappear, the tone of the uterus decreases or increases. The mammary glands become sluggish. There may be a violation of general well-being, unexplained weakness, malaise, pain and heaviness in the lower abdomen. Evidence of stillbirth is the absence of a heartbeat.
Fetal death in multiple pregnancies
Intrauterine fetal death is detected in 6% of multiple pregnancies. The probability of development depends on the number of fruits and chorions. The greater the degree of multiple pregnancy, the higher the risk of death of one of the twins. In the presence of a common chorion, the probability of death of one of the fetuses increases several times compared to dichoric twins. The immediate causes of stillbirth are intrauterine growth retardation, placental abruption, severe gestosis, chorioamnionitis or the formation of arteriovenous anastomosis with common chorion.
The form of pathology depends on the time of fetal death. In the early stages of pregnancy (up to 10 weeks), the phenomenon of the “missing twin” is observed. The dead embryo is rejected or absorbed. In the presence of two chorions, the death of one twin does not affect the development of the other in any way. With a common chorion, the second twin increases the likelihood of cerebral palsy and intrauterine development delay. Stillbirth in such cases often remains unrecognized and is regarded as a threat of termination of pregnancy.
At death at the end of the first or the beginning of the second trimester of pregnancy, the deceased fetus does not disappear, but is mummified. It is squeezed by the increasing fetal bladder of a brother or sister, “dries up” and decreases in size. With a common chorion, the second twin often has congenital malformations caused by the entry of decay products into the body through the general circulatory system.
From 9-10 weeks, the absence of heart contractions is detected during ultrasound, from 13-15 – when using fetal phonocardiography or electrocardiography. After 18-20 weeks, the absence of a heartbeat is determined by normal auscultation. To confirm the diagnosis, additional studies are prescribed: ultrasound, cardiotocography, blood tests for hormones.
Characteristic signs of stillbirth are a decrease in the level of estriol, progesterone and placental lactogen. During amnioscopy, greenish amniotic fluid is detected during the first day (the change in the color of the waters is due to the presence of meconium). Subsequently, the color of the waters becomes less intense, sometimes an admixture of blood is detected. In some cases, radiography is used in the process of diagnosing stillbirth. X-rays determine the gas in the subcutaneous fat, heart and large vessels of the fetus.
The relative position of the bones of the skeleton is violated. The edges of the skull bones come on top of each other or diverge, forming a “step”. In the first case, there is a decrease in the head, in the second – flattening or a kind of bag-like elongation of the skull. The fetal head may be tilted to the side. The spine is also deformed. Its straightening, lordosis or angular deformation are possible. The fetal limbs are arranged chaotically. During petrification, deposits of calcium salts are visible in the amniotic membrane, trunk and extremities. With intravenous urography of the patient, the fetal kidneys are not contrasted.
If the fetus dies in the first trimester, a miscarriage is possible. If a miscarriage does not occur, a medical abortion is performed. At death in the second trimester, the fetus is usually not expelled independently, urgent delivery is necessary. After a comprehensive examination and examination of the state of the patient’s blood coagulation system, labor is performed. First, estrogens, glucose, vitamins and calcium preparations are injected, then oxytocin and prostaglandins are prescribed. To accelerate the first period of labor, an amniotomy is performed.
With stillbirth in the third trimester, independent childbirth is possible. In the absence of labor, stimulation is prescribed. According to the indications, fruit-destroying operations are carried out. With hydrocephalus, frontal and pelvic presentation, the threat of rupture of the uterus and a serious condition of the patient, craniotomy is performed. With a running transverse presentation, decapitation or evisceration is performed, with a delay of the shoulders in the birth canal, a kleidotomy is performed.
Tactics for multiple pregnancies
In case of multiple pregnancy and suspected stillbirth, immediate hospitalization is indicated for examination and resolution of the issue of pregnancy management tactics. During the examination, the gestation period and the number of chorions are determined, the condition of the living fetus is assessed, somatic diseases and diseases of the mother’s reproductive system are detected. With general chorion and stillbirth diagnosed at the beginning of the second trimester, parents are advised to consider terminating pregnancy due to the high risk of intrauterine pathology in the second twin.
At the time of 25-34 weeks of gestation, a thorough examination of the surviving fetus (ultrasound, MRI) is necessary. With a satisfactory condition of the fetus, prolongation of pregnancy is indicated. The need for urgent delivery in case of stillbirth is determined taking into account the condition of the mother and the surviving child, the likelihood of intrauterine disorders and the risk of complications due to prematurity.
Indications for delivery on the part of a pregnant woman are somatic diseases and diseases of the reproductive system that prevent the prologue of pregnancy. Relative indications on the part of the fetus are anemia, terminal blood flow and the threat of fetal death in arteriovenous anastomoses. Stillbirth after 34 weeks of multiple pregnancy is considered as an absolute indication for delivery.
In the presence of two chorions, urgent delivery is usually not required. The patient is placed under constant supervision, which includes daily monitoring of temperature, blood pressure, edema and discharge, as well as regular tests to assess the state of the blood coagulation system. The condition of a living fetus is assessed by the results of dopplerometry of uteroplacental blood flow, biometrics and echography of the brain. After birth, an autopsy of the deceased twin is performed and the placenta is examined to identify the cause of stillbirth.
Prevention of stillbirth includes timely detection of genetic abnormalities, diagnosis and treatment of somatic diseases, rehabilitation of chronic foci of infection, rejection of bad habits, cessation of contact with household toxic substances, elimination of occupational hazards, injury prevention and thoughtful prescription of medications during pregnancy.