Twin births increases risk of complications, writes Dr Muiris Houston, Medical Correspondent.
The death of a woman in her 30s and one of her twin babies at Our Lady of Lourdes Hospital, Drogheda, is both a tragedy and a rare event.
While there were no maternal deaths in the Republic in 2002 and 2003, the maternal mortality rate for 2000 was below two deaths per 100,000 live-births and stillbirths.
Mothers of twins are at increased risk of a number of pregnancy complications, including miscarriage, premature labour, pre and post birth haemorrhage and pregnancy related high blood pressure (pre-eclampsia).
They are also more likely to require delivery by Caesarean section. The latest figures from the National Perinatal Reporting System show that 58 per cent of multiple births were by Caesarean in 2003.
Clot formation in the leg leading to a pulmonary embolus is one of the causes of maternal death. Another is haemorrhage; antepartum bleeding occurs before labour and is due to either a low-lying placenta or a placenta that becomes partly detached from the wall of the womb.
Postpartum haemorrhage is more common and occurs after the babies have been delivered when the womb fails to contract adequately with the result that the mother bleeds heavily.
Untreated pre-eclampsia can cause stroke, seizures and acute renal failure with a consequent risk of death.
Maternal death from infection is rare in the developed world. Other causes such as rupture of the womb and deaths from anaesthesia during Caesarean section are also quite rare.
Twins occur in approximately 1 in 80 pregnancies. There were 873 twins and 26 triplets born in the State in 2003. The risk of neonatal death is greater for twins than for single babies. While the overall perinatal mortality rate was 8.6 per 1,000 live and still births in 2003, the rate for multiple births was 28 per 1,000.
Premature labour is five times more likely in a twin pregnancy. Twins are also more likely to experience growth retardation in the womb.
And while the death of one foetus in a twin pregnancy can happen at any point, it occurs at 20 weeks gestation or later in just 2.6 per cent of twin pregnancies.
When one twin dies in the uterus there is a risk to the health of the co-twin. This usually occurs because of a severe drop in blood pressure during the death of the first twin.
While there are greater risks to both the mother and her babies in a twin pregnancy, our maternal mortality and perinatal death rates compare favourably with those of other countries in the developed world.