How to recognize premature births?
Last reviewed: 23.04.2024
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Diagnosis of preterm labor
Allocate menacing, beginning and started premature birth.
In case of threatening premature birth the woman complains of drawing, aching pains in the lower abdomen and lower back, sensation of pressure, vaginal discharge, crotch, rectum, possibly painful urination, which may be a sign of low position and pressure of the presenting part. Regular labor is not available, individual uterine contractions are recorded. Excitability and tone of the uterus are increased.
Vaginal examination: the cervix is formed, the length of the cervix is more than 1.5-2 cm, the external pharynx is either closed or in the re-parenting women passes the tip of the finger, in some cases the lower uterine segment is stretched by the presenting part of the fetus that is palpated in the upper or middle third of the vagina .
Ultrasound: the length of the cervix is 2-2.5 cm, the cervical canal is widened to no more than 1 cm, the fetal head is located low.
Dynamic control of the pregnant woman is as important as possible by one specialist due to the individual characteristics of the cervix in each woman. In the presence of dynamics in the form of softening, shortening of the cervix, as well as the condition of the external, internal pharynx or cervical canal, it is a question of beginning premature birth.
With the beginning of preterm birth, cramping pains in the lower abdomen and lower back, or regular bouts with an interval of 3 to 10 minutes. When vaginal examination, the length of the cervix is less than 1.5 cm, the cervical canal is passed for the finger, with the progression of labor, the cervix is smoothed and opened.
The beginning of premature birth is characterized by regular contractions and cervical dilatation more than 3-4 cm. As a rule (but not necessarily), the amniotic fluid flows. Record regular uterine contractions every 3-5 minutes.
Diagnosis is based both on the complaints of the pregnant woman, and on the objective evaluation of the contractile activity of the uterus and the dynamic change in the state of the cervix during the vaginal examination.
With threatening or beginning premature birth, a tactic aimed at prolonging pregnancy is possible.
With the beginning of preterm labor, leakage of amniotic fluid, signs of infection, severe extragenital pathology, active tactics of labor management is expedient (refusal from further prolongation of pregnancy).
[Special research methods
Actions during a survey of a pregnant woman who complains of pulling pains in the lower abdomen and lower back.
- Eliminate the factors leading to complications of preterm labor:
- premature discharge of amniotic fluid (smear on elements of amniotic fluid, amnesty);
- premature detachment of the normally located placenta (the nature of secretions, the detection of local tonus and soreness, ultrasound confirmation);
- placenta previa according to ultrasound.
- Conduct an assessment of the fetus (according to the methods of functional diagnostics - ultrasound, CTG):
- listen to the fetal heartbeat;
- eliminate fetal development abnormalities;
- to estimate the number of amniotic fluid (polyhydramnios, low water);
- accurately determine the gestational age and body weight of the fetus, compare the mass-growth indices to detect a delay in the intrauterine development of the fetus;
- conduct a non-stress test (CTG data) during gestation more than 32 weeks.
- Identify or eliminate signs of infection with:
- sowing urine to detect asymptomatic bacteriuria;
- bacteriological study and PCR of the vaginal discharge and cervical canal (detection of group B Streptococcus, gonorrhea, chlamydial infection);
- microscopy of a vaginal smear (detection of bacterial vaginosis, vulvovaginitis);
- thermometry, clinical blood analysis with the study of the leukocyte formula for the diagnosis of chorioamnionitis. The length of the cervix, measured by ultrasound with a transvaginal sensor, makes it possible to distinguish the risk group of preterm labor.
Before 20 weeks of gestation, the length of the cervix is very variable and can not serve as a criterion for diagnosing the occurrence of premature births in the future. In 24-28 weeks, the average length of the cervix is 45-35 mm, in 32 weeks and more - 35-30 mm. Shortening of the cervix to 25 mm or less in 20-30 weeks of pregnancy is a risk factor for premature birth.
Differential diagnosis of preterm labor
In case of threatening premature births, the main symptom of which is pain in the lower abdomen and lower back, differential diagnostics is performed with abdominal cavity pathology, first of all with intestinal pathology (spastic colitis, acute appendicitis), kidney and urinary tract diseases (pyelonephritis, urolithiasis, cystitis).
If there are pains in the area of the uterus, it is necessary to exclude the necrosis of the myoma node, the incompetence of the uterine cicatrix.