OBSTRUCTED LABOUR DEFINITION It is Failure of delivery of the fetus due to mechanical obstruction. AETIOLOGY Maternal causes: Contracted pelvis. Soft tissue obstruction e.g. fibroid, ovarian tumors impacted in Douglas pouch. Cervical dystocia. Other less common causes include: contraction ring, vaginal stricture or septum, vulval edema, hematoma or neoplasma and rigid perineum. Fetal causes: Macrosomia: large fetus more than 4 kg. Malpresentations Shoulder dystocia: difficulty in delivery of the shoulders Locked twins: very rare CLINICAL PICTURE "Impending rupture of the uterus": History: History of a prolonged labor, inspite of the presence of good uterine contractions, with prolonged rupture of membranes (ROM). General examination: The patient is exhausted due to prolonged labor. Signs of dehydration are commonly evident; blood pressure is low, temperature is elevated, pulse is rapid, tongue and mucus membranes are dry. Abdominal examination: The uterus is hard and tender, contractions are rapid and strong. Pathological retraction ring = BANDL'S RING is seen and felt as a transverse or oblique groove across the abdomen. The ring rises with time. Fetal parts are difficult to palpate F.H.S. are inaudible or show severe distress. Differential diagnosis of pathological retraction ring: Full bladder (excluded by catheterization). Fundal fibroid (not rising - no signs of obstruction). Contraction ring. Pathological retraction ring Contraction Ring Occurs with prolonged second stage Occurs during any stage Always lies between the upper and lower At any level of the uterus segments Rises up Does not change its position Seen abdominally Not seen abdominally The uterus is tonically retracted, tender The uterus is not tonically retracted and and fetal parts cannot be felt fetal parts can be felt The mother is distressed and the fetus is The mother and the fetus are not distressed or dead necessarily distressed Relieved only by delivery May relax by antispasmodics or anesthesia Vaginal examination: The vulva becomes oedematous, and the vagina becomes dry. The cervix feels oedamatous, not well applied on the presenting part unless fully dilated. The presenting part is not engaged, pelvic caput succidanum commonly develops in the fetal scalp in vertex presentation. This is of particular importance as. The cause of obstruction is determined: (Disproportion, Persistent OP, Neglected shoulder etc….) COMPLICATIONS OF OBSTRUCTED LABOUR Maternal distress, exhaustion, and dehydration. Fetal distress, hypoxia and neonatal asphyxia. Prolonged rupture of membranes (with its complications). Intra-amniotic infection. Rupture uterus (overstretch of lower uterine segment). Injuries of birth canal: cervical, vaginal and perineal lacerations. Puerperal infection due to: - Prolonged labour with prolonged rupture of membranes. - Intrauterine manipulations and possible genital tract lacerations. Necrotic obstetric vesico-vaginal fistula (due to prolonged head compression). High perinatal mortality (neonatal asphyxia, fetal birth injuries, and sepsis). MANAGEMENT OF OBSTRUCTED LABOUR: Immediate C.S. with least possible manipulations is the safest choice Difficulties encountered during the procedure include: Extension of lower segment incision and subsequent injury of the uterine vessels Difficulty in extraction of the fetus due to impaction of the presenting part These problems could be avoided by dis-impaction of fetal head vaginally, making an adequate uterine incision and gentle extraction of the fetus. Exploration of the birth canal (under anesthesia) is essential after any vaginal manipulation to exclude any traumatic lesion especially rupture uterus. Forceps delivery should not be attempted as it carries a high risk of complications especially rupture uterus.