COMPLICATIONS OF LABOR Premature Labor Divided in two:- Spontaneous preterm labor Preterm pre-labor rupture of membranes(PPROM)

WHO definition Preterm labor is the presence of contractions of sufficient strength and frequency to effect progressive effacement and dilatation of the cervix between 20 and 37 weeks’ gestation

Preterm labor is considered to be established if regular uterine contractions can be documented at least 4 in 20 minutes or 8 in 60 minutes with progressive change in the cervical score in terms of effacement of 80% or more and cervical dilatation of more than 1cm

The leading cause of perinatal morbidity and mortality Survival rates have increased and morbidity has decreased because of technologic advances

Classification Preterm Delivery Preterm birth: < 37completed weeks Very Preterm birth: < 32 weeks Extremely Preterm birth: < 28 weeks

Survival by gestational age among live-born resuscitated infants

Incidence of preterm births Preterm birth occurs in 5-12% of all pregnancies and accounts for majority of congenital neurological disability including cerebral palsy

Risk Factors for Preterm Birth Non-modifiable Previous preterm birth Age <18 or >40 years Poor nutrition/low pre pregnancy weight Low socioeconomic status Cervical injury or anomaly Uterine anomaly or fibroid Premature cervical dilatation (>2 cm) or effacement (>80 percent) Over distended uterus (multiple pregnancy, polyhydramnios) Modifiable Cigarette smoking Substance abuse Absent prenatal care Short interpregnancy intervals Anemia(hemoglobin <10 g/dL) Bacteriuria/urinary tract infection Genital infection

Risk factors for preterm birth cont..d Stress Single women Low socioeconomic status Anxiety Depression Life events (divorce, separation, death) Abdominal surgery during pregnancy Occupational fatigue Upright posture Use of industrial machines Physical exertion Mental or environmental stress Excessive or impaired uterine distention Multiple gestation Polyhydramnios Uterine anomaly or fibroids Cervical factors History of second trimester abortion History of cervical surgery Premature cervical dilatation or effacement Infection Sexually transmitted infections Pyelonephritis Systemic infection Bacteriuria Periodontal disease Placental pathology Placenta previa Abruption Vaginal bleeding

Risk Factors cont..d Fetal factors Congenital anomalies intrauterine growth restriction Intrauterine fetal death Uterine causes Myomata (particularly submucosal or subplacental Bicornuate uterus Cervical incompetence

Infections associated with preterm delivery Genital * Bacterial vaginosis (BV) * Group B streptococcus * Chlamydia * Mycoplasmas Intra-uterine * Ascending (from genital tract) * Transplacental (blood-borne) * Transfallopian (intraperitoneal) * Iatrogenic (invasive procedures) Extra-uterine * Pyelonephritis * Malaria * Typhoid fever * Pneumonia * Listeria * Asymptomatic bacteriuria 11

Ascending intrauterine infections stage I changing flora vagina/cervix, II Microorganism alocated between the amnion and chorion, III intra amniotic infection, IV fetal invation The preterm parturition syndrome. Multiple pathologic processes can lead to activation of the common pathway of parturition. In: Creasy, Resnik . Maternal – Fetal Medicine, 2009 12

Diagnosis Documented uterine contractions(4 in 20 minutes or 8 in 60 minutes) Documented cervical change (cervical effacement of 80% or cervical dilatation of 2cm or more) Ultrasound examination of cervical length Fetal fibronectin (fFN) levels detectable in vaginal secretions

Management of Preterm Labor An initial assessment: ascertain cervical length and dilatation and the station and nature of the presenting part Bed Rest : be place patient in lateral decubitus Hydration Sedation

Beta 2 adrenergic receptor agonists (Terbutaline) Tocolytic Therapy Beta 2 adrenergic receptor agonists (Terbutaline) Mechanism of action decreases free intracellular calcium ions Inhibits actin myosin interaction Side Effects Tachycardia, palpitations, hypotension, SOB, pulmonary edema, hyperglycemia Contraindications Maternal cardiac disease, uncontrolled diabetes and hyperthyroidism

Magnesium Sulfate Mechanism of Action Side Effects Contraindications Competes with Calcium at plasma membrane Side Effects Diaphoresis, flushing, pulmonary edema Contraindications Myasthenia gravis, renal failure

Calcium Channel Blockers Example: Nifedipine Mechanism of Action Directly block influx of Ca through cell membrane Side Effects Nausea, flushing, palpitations Contraindications Caution: LV dysfunction, CHF

Tocolytic therapy may offer some short-term benefit in the management of preterm labor A delay in delivery can be used to administer corticosteroids to enhance pulmonary maturity and reduce the severity of fetal respiratory distress syndrome Can also be used to facilitate transfer of the patient to a tertiary care center

Other Drugs Antenatal Steroids Dexamethasone: dosage 6 mg q 12 h Betamethasone: dosage 12.5 mg q 24 h Indicated for fetal maturation Reduces fetal mortality, respiratory distress syndrome and intraventricular hemorrhage in infants between 28 and 34 weeks of gestation Benefits start at 24 hours and last up to seven days after treatment

Antibiotic Therapy Studies have shown that women who receive antibiotics sustain pregnancy twice as long as those who do not receive antibiotics A lower incidence of clinical amnionitis. Poor fetal outcome (death, respiratory distress syndrome, sepsis, intraventricular hemorrhage or necrotizing colitis) occur less frequently in women receiving antibiotics

Management during labor and delivery With modern neonatal care, the lower limit of potential viability is 24 weeks or 500g, although these limits vary with the expertise of the neonatal intensive care unit Continuous fetal heart monitoring and prompt attention to abnormal fetal heart rate pattern are extremely important With a vertex presentation, vaginal delivery is preferred.

Labor and delivery cont,.d Use of vacuum extraction and episiotomy to shorten the second stage are advocated. Cesarean section for delivery of the very low birth weight baby For the breech fetus estimated at less than 1500g, neonatal outcome is improved by cesarean section

Evaluation of patients with preterm labor History Evaluate the following symptoms Uterine contractions Rhythmic low back pain Pelvic pressure Increased vaginal discharge Vaginal bleeding(bloody show)

Physical Examination Uterine tenderness on abdominal examination Sterile speculum examination may reveal pooling of amniotic fluid, blood and/or abnormal discharge may be observed Visual assessment of cervical dilatation Digital examination should be limited as may stimulate prostaglandins

Preterm Pre-labor Rupture of Membranes(PPROM) Spontaneous rupture of fetal membranes occurring before 37 weeks of gestation(prior to the onset of labor ) Diagnosis History of sudden escape of watery amniotic fluid Differentiate it from stress urinary incontinence and profuse normal vaginal discharge

Incidence PROM occurs in about 10-15% of all deliveries PROM is associated with 10% of term deliveries

Causes The cause of PROM is not clearly understood, but is associated with the following factors:- Trauma Sexual intercourse (particularly in the late gestational weeks) --Lax of internal os of uterine

Vaginal infection due to bacteria, viruses e. g Vaginal infection due to bacteria, viruses e.g. Toxoplasmosis, CMV, HPV, HSV STIs play an important role in the cause of PROM Increased of intra-uterine pressure (such as multiple pregnancy and polyhydramnios) Abnormalities in presentation and position

Smoking: The risk of PROM is at lease doubled in women who smoke during pregnancy Other risk factors for PROM include:- Prior PROM A short cervical length Prior preterm delivery Bleeding in early pregnancy

Manifestations Fluid passing through the vagina suddenly, and then small amounts intermitently particularly with increased abdominal pressure (cough, sneeze, etc) Intermittent urinary leakage is common during pregnancy, especially near term Increased vaginal secretions in pregnancy Perineal moisture Increased cervical discharge Urinary incontinence

Diagnosis A sterile speculum examination confirms that the fluid is coming through the os Ultrasound examination shows oligohydramnios Fern test-placing a sample on a microscopic slide, air drying, and examining for ferning The amniotic fluid does fern The other fluid do not fern

Nitrazine test- uses pH to distinguish amniotic fluid from urine and vaginal secretions, the paper turns dark blue from yellow in response to the amniotic fluid

Complications of PPROM Maternal complications Preterm delivery Chorioamnionitis Placental abruption Retained placenta PPH Endometritis

Fetal and neonatal complications Fetal and neonatal pneumonia Neonatal respiratory distress syndrome Neurologic dysfunction Intracranial hemorrhage Prolapse of umbilical cord Abruptio placenta Prematurity Pneumonia and early neonatal sepsis Pulmonary hypoplasia Fetal death

Management of PPROM Correct and prompt diagnosis Surfactant therapy Conservative management after ruling out cord complications e.g. cord prolapse, cord compression, placental abruption and fetal distress Antibiotic therapy may prolong the latency period after preterm PROM and improve the perinatal outcome Corticosteroids given between 24 and 34 weeks gestation to enhance fetal pulmonary maturity

Fetal surveillance by non stress test and biophysical profile done daily Delivery must be planned when: There is evidence of clinical infection e.g. chorioamnionitis Non reassuring features on fetal monitoring when pregnancy has reached 34 weeks PPROM at 34-36 weeks- induce labor unless fetal lung maturity or gestational age is doubtful

If PROM occurs at term(37 weeks’ gestational age or more), awaiting the onset of spontaneous labor for 12-24h should be considered, because spontaneous labor will ensue in 90% of patients within 24 hours If the time from PROM to the onset of labor exceeds 24h, induction of labor should be considered by oxytocin

If the evaluation suggests intrauterine infection or chorioamnionitis, antibiotic and delivery are indicated and the antibiotic prescribed should have a broad spectrum of coverage If the infant is a preterm breech, and the onset of PROM occurs after 30 weeks’ of gestation, delivery is possibly by cesarean delivery

If the gestational age is less 30 weeks’, vaginal delivery should be chosen If the fetus is significantly preterm with absence of infection, expectant management is generally chosen

Patients assessment Uterine tenderness daily Frequent electronic fetal monitoring Fetal movement monitoring by the mother Frequent ultrasound assessment helps to determine amniotic fluid Frequently WBC counts, usually daily for several days