The Effect of Twins on Labour
Although, multiple pregnancy may not be regarded as abnormal in itself, many complications that endanger fetal and maternal life do arise . Labour is often preterm: the babies tend to be light for date even when at term.
The perinatal mortality rate is higher than in single births. The mortality rate of the second twin is twice that of the first, and this may be due to reduction in the placental circulation and partial separation of placenta following the birth of the first twin.
Malpresentation is more common. For these reasons hospitalization for delivery is advocated.
Heavy sedation should be avoided.
Epidural analgesia may be use.
If delay occurs due to hypotonic uterine action after the delivery of the first twin an oxytocin drip may be given after puncture of the membranes and kept running until one hour after both babies and placenta are delivered.
Preparations should be made for the reception of two immature babies, who may show signs of asphyxia or intracranial injury.
Woman should be observed for signs of shock due to sudden reduction in abdominal pressure.
The woman may be more comfortable in the dorsal position with additional pillows.
Perineal infiltration or pudendal nerve block is commonly employed and an episiotomy is made in an endeavour to lower thehigh perinatal mortality rate.
The airway of the first baby is cleared. The cord should be ligatured in two places, for although the placental end of the cord is tied or clamped at every delivery, it is because of the possibility of undiagnosed monozygotic twins that this is done. The first baby, after being marked No. 1, is laid in a warm cot and the midwife keeps her 'ear and eye on it.
The abdomen is palpated without delay to ensure that the lie of the second twin is longitudinal. Presentation and position are diagnosed, but are of less importance: the fetal heart is listened to. The midwife stands by. She will closely observe the uterus, probably keeping her hand lightly on it to detect uterine contractions. The fetal heart should be checked frequently.
With three or four good contractions and the woman pushing effectively the second baby ought to be born. But if, when 5 minutes have elapsed, contractions have not recommenced, the midwife should scrub up and after making sure that the head or the breech is presenting she should puncture the bag of membranes and massage the uterus to stimulate uterine action. The second baby should be born within 15 minutes after the first baby.
Ergometrine, 0.5mg or Syntometrine, 1ml, should be given intramuscularly as soon as both placentae are born to prevent postpartum haemorrhage. If Syntometrine is given inadvertently after the birth of the first baby, the second baby must be expelled immediately by fundal pressure. Midwives must always remember the possibility of an undiagnosed twin when they administer Syntometrine during the actual birth of a baby. The woman should not be left until at least two hours after the birth of the palcentae and to ensure sleep a sedative is given.
Avoid unnecessary delay in the delivery of the second as this may result in:
The fetus in utero may die of anoxia should the palcenta separates.
The risk of sepsis is increased when the cord is lying outside the vulva.
The cervix closes to a certain extent and will have to dilate again. Having ensured that the lie is longitudinal, the doctor will probably puncture the membranes, and give an oxytocin drip, when the uterus begins to contract he may apply forceps or use the Malmstrom vacuum extractor.
The expulsion of a placenta or bleeding before the birth ofthe second twin gives warning that the placenta still in- utero may also be separating and causing hypoxia of the unborn twin; in which case, the midwife should massage the uterus and expel the second twin as soon as possible by using fundal pressure. (The usual sequence of events is for both babies to be born and then the placentae).
Locked twins are very rare indeed, and the most seriousvariety occurs when the first fetus is presenting by the breech and the head of the second fetus which is presenting by the vertex gets in front of the after coming head of the first baby. The heads become impacted and decapitation of the head of the first baby is usually necessary.
Involution of the uterus may be slow; after pains are more troublesome. The care of the babies is a most urgent problem, as the number of twin babies who die is alarmingly high, the smaller one may be light for date. The mother will need help and advice in regard to feeding, and should not be discharge from hospital until the babies are gaining weight satisfactorily.