Definition:- When there is more than one fetus is in utero, the term, plural or multiple pregnancy is applied.
Twin pregnancy occurs approximately 1 in 100 pregnancy Triplets occur 1 in every 8000- 9000 pregnancies.
1. Monozygotic (Uniovular)
2. Dizygotic (Binovular)
Monozygotic or single ovum twins are known as identical twins. Monozygotic twins develop from one ovum which has been fertilized by one spermatozoon, always of same sex, they share one placenta and one chorion. A few have two chorions. There is a connection between the circulations of blood in the two babies. Finger and palm prints are identical. Errors in development are more likely in monozygotic twins and conjoined twins are more common.
Diazygotic or double ova twins develop from the fertilization of two ovum and two spermatozoa and are more common than monoazygotic twins.
These twins have two placenta may be fused to form one amniotic sacs, two chrions and no connection between fetal circulations. The babies may or may not be of the same sex and their physical and mental characteristics can be as different as in any members of one family.
Table 5. Difference between monozygotic and dizaygot twins
One fetus may be died and be retained in uterus until term, when it will be expelled with the placenta as a flattened paper like fetus called a fetus papyraceous. Twin babies are small and often preterm.
Diagnosis of twin pregnancy may be difficult, although a family history of twins should alter the midwife to the possibility. Ultrasound: -it will demonstrate two heads at 15 weeks whenthe outline of the head will be noted
X -ray- may be used after the 12thweek of gestation.
Inspection:-the size of the uterus may be larger thanexpected for the period of gestation after the 20th week. Palpation:-The fundal height may be greater than expectedfor the period of gestation.
· The presence of two fetal poles (head or breech) multiple fetal limbs.
· Lateral palpation may reveal two fetal backs or limbs on both sides.
· Pelvic palpation one fetus may lie behind the other and make palpation difficult.
Auscultation:-Hearing two fetal hearts is not diagnostic.Comparison of the heart rates should reveals difference of at least 10 beats per minutes.
· Exacerbation of minor disorder
· Nausea, Morning Sickness and heart burn may be more persist.
· Iron deficiency or folic acid deficiency anaemias are common. Early growth and development of the uterus and
· its contents make greater demands on maternal iron stores. In later pregnancy (after the 28th week) fetal demands for iron deplete those stores further.
· Pregnancy induced Hypertension
o More common in twin pregnancies May be associated with the larger placenta site or the increased hormonal out put the incidence tends to be greater in monozygotic twin pregnancies.
o It is common and associated with monozygotic twins and with fetal abnormalities. If acute polyhydraminos occurs it tends to lead to abortion.
· Pressure symptoms
. Tendency to oedema of ankle and varicose veins isincreased
. Dyspnoea and indigestion are more marked,backache is common.
· Early diagnosis is important so as to provide dietary
· advice on iron folic acid and vitamins which help to keep her haemoglobin level normal
· Frequent antenatal check up to detect P.I.H.
· Admission to hospital for relief discomfort in later pregnancy.
Effect on labour: - Labour occurs spontaneously before term due to over stretching of the uterus or may be induced early if complications arise. Preterm labour, babies light for dates and malpresentation.
1st stage of labour: - should be conducted normally,preparation should be made for the reception of two immature babies. Good nursing care to alleviate minor discomfort. If fetal distress occurs during labour, delivery will need to be expedited, often by caesarean section. If the uterine activity is poor the use of intravenous oxytocin may be required. If the pregnancy is preterm neonatal care unit should be informed. Two incubators should be in readiness. The room should be warm.
2nd stage of labour: - An obstetrician, anesthetist andpaediatrician should be present during this stage of labour because of the risk of complication.
Resuscitation equipment should be prepared. The delivery trolley should include equipments for episiotomy, aminiotomy forceps, and extra cord clamp and equipment for delivery.
An elective episiotomy may be considered if there are complication like preterm labour and fetal distress. The second stage is conducted as usual up to the birth of the first baby. After delivery of the first twin an abdominal examination is made to ascertain the lie, presentation and position of the second fetus and to auscultate the fetal heart. If the lie is not longitudinal, an attempt is made to correct it by external cephalic version.
If the presenting part is not engaged it should be pushed in to the pelvis by fundal pressure before the second sac of membranes is ruptured. Stimulate the contraction with IV syntocinon. When the presenting part became visible the mother is encouraged to push with contraction to deliver the second twin.
With three or four good contractions and effective pushing the 2nd baby has to be delivered with in 15 minutes. The babies are labeled as ‘ Twin one ‘ and ‘Twin two’ a note of the time of delivery and the sex of the child is made.
3rd Stage of Labour:-An oxytoxic drug has taken effect,controlled cord traction is applied to both cords simultaneously and delivery of the placenta should be effected with out delay. Emptying the uterus enables the control of bleeding and the prevention of post partum haemorrhage.
The placenta should be examined for completeness and to detect deviation from the normal. The umbilical cords should be examined for the number of cord vessels.
Delay in the birth of the second twin
After delivery of the 1st twin, contraction has to start with in 5 minutes.
• Poor uterine action
• Malpresentation of the second twin
Dangers (risk of) Delay
I. Intra uterine hypoxia, IUFD
II. Birth asphyxia following premature separation of placenta
III. Sepsis- an ascending infection may reult from from the first umblical cord which lies out side of the vulva.
IV. The cervix closes to certain extent and will have to dilate again
Managements of closed cervix
Stimulate the contraction put the baby on the breast. If the lie is longitudinal the doctor will rupture the membranes and give an oxytocic drug. When the uterus begins to contracts he may apply forceps. If there appears obstructed caesarean section may be necessary.
• Transverse lie of the second twin
If the lie is transverse call the doctor and he/she attempts external version between contraction if the membranes are intact. Also after internal version may be a breech extraction may be done with intact membrane.
Premature expulsion of the placenta or bleeding before the birth of the second twin results in hypoxia of the unborn twin.
Management - Massage the uterus and expel the 2nd twin by fundal pressure
• Post parrtum haemorrhage
• Premature rupture of the membrane
• Prolapse of the cord
• Prolonged labour - malpresentation, poor uterine action
In the second stage of labour the after coming head of the first twin may be prevented from descending into the pelvis by the head of the second twin.
· Both twins presenting by the vertex
· Twin one - breech presentation
Twin two - vertex presentation
Danger - Obstructed labour
Management - caesarean section
· Fetal abnormality
· Premature rupture of membrane
· Prolapse of cord
· Prolonged labour
· Locked twin
· Post partum hemorrhage
Care of the babies maintenances of body temperature, hygiene to prevent infection.