Premature rupture of the amniotic membrane: what’s new in its management and delivery tactics?

Abstract

Background. Premature rupture of the amniotic membranes (PRAM) is a spontaneous rupture before the onset of labor at 22-37 weeks. The main complications of PRAM for mother and fetus include infection, premature birth, asphyxia of the fetus during labor, and the increased frequency of cesarean sections. Deformations of extremities, face and lungs are observed in case of a long oligohydramnion (>3 weeks). Objective. To describe the features of the management of pregnant women with PRAM. Materials and methods. Analysis of literature sources on this topic. Results and discussion. Gynecological and extragenital pathology of mother, genetic predisposition, adverse environmental factors and infections are risk factors for PRAM. Prevention of PRAM includes detection and treatment of urogenital infections, quitting of smoking and alcohol intake, screening for bacteriuria and bacteriological culture for β-hemolytic streptococcus (BHS) at 35-37 weeks of pregnancy. From 22 to 34 weeks of pregnancy, pregnant women with PRAM are hospitalized to the tertiary level hospitals, since 35 weeks care can be provided in secondary level hospitals. The management algorithm is the following: 1) history taking; 2) establishment of gestational age; 3) establishment of the approximate time of PRAM; 4) general physical examination; 5) external obstetric examination; 6) cardiotocogram (CTG), tests of fetal movements (TFM), ultrasonography (US); 7) blood test with leukocyte formula, determination of C-reactive protein; 8) bacterioscopic examination of vaginal discharge; 9) collection of amniotic fluid for microbiological examination, study of rectogenital smear for BHS; 10) sanitation of the vagina with a solution of antiseptic decamethoxine after collection of vaginal secretions and amniotic fluid. PRAM management involves active or waiting tactics. Waiting tactic includes monitoring of the fetus and mother (thermometry and pulsometry, the number of leukocytes and C-reactive protein, bacterioscopy of vaginal discharge, CTG, TFM, US). Antibiotic prophylaxis (semi-synthetic penicillins + macrolides, reserve – second-generation cephalosporins) in PRAM significantly prolongs the latent phase of delivery, reduces the incidence of infections in both mother and newborn, reduces the need for surfactant and oxygen therapy. In the presence of chorioamnionitis, delivery should be performed within <12 hours. In case of PRAM in the term of 24-34 weeks the course of corticosteroids is administered. Delivery delay for 48 h for steroid prophylaxis is the main indication for tocolysis in PRAM. In general, the tactics of pregnancy management in PRAM at 24-34 weeks include monitoring of the mother and fetus, steroid prophylaxis, tocolytic therapy and the use of magnesium sulfate. Waiting tactic should be followed until 34 weeks. In women with PRAM without contraindications to prolonging pregnancy, the waiting tactic is accompanied by better results for both mother and fetus. Signs of infection or other complications of pregnancy indicate the need for termination of the waiting tactic and delivery management according to the clinical situation. Within 34-37 weeks, the waiting tactic is followed for 24 hours. Antibiotic prophylaxis is prescribed after 18 hours of anhydrous interval, and in case of BHS – immediately after PRAM. In the absence of active labor process, an internal obstetric examination is performed to decide the tactics of delivery. Other procedures include cervix preparation, induction of labor and washing of the vagina with decamethoxine solution. Cesarean section is indicated for PRAM at 26-32 weeks and immaturity of the birth canal. Conclusions. 1. Hospitalization and delivery in women with PRAM is carried out in hospitals of secondary and tertiary level. 2. Routine use of antibiotics in PRAM prolongs the latent phase of delivery and reduces the incidence of neonatal sepsis. 3. Waiting tactic in pregnant women with PRAM in the period of 24-34 weeks is accompanied by good outcomes for both mother and child. 4. Pregnant women with PRAM in 24-34 weeks should be treated with corticosteroids to prevent acute respiratory distress syndrome in neonates.