8.7.3 Consequences of twin pregnancy
Women who are pregnant with twins are more prone to suffer with the minor disorders of pregnancy, like morning sickness, nausea and heartburn. Twin pregnancy is one cause of hyperemesis gravidarum (persistent, severe nausea and vomiting). Mothers of twins are also more at risk of developing iron and folate-deficiency anaemia during pregnancy.
Can you suggest why anaemia is a greater risk in multiple pregnancies?
The mother has to supply the nutrients to feed two (or more) babies; if she is not getting enough iron and folate in her diet, or through supplements, she will become anaemic.
Other complications include the following:
- Pregnancy-related hypertensive disorders like pre-eclampsia and eclampsia are more common in twin pregnancies.
- Pressure symptoms may occur in late pregnancy due to the increased weight and size of the uterus.
- Labour often occurs spontaneously before term, with premature delivery or premature rupture of membranes (PROM).
- Respiratory deficit (shortness of breath, because of fast growing uterus) is another common problem.
Twin babies may be small in comparison to their gestational age and more prone to the complications associated with low birth weight (increased vulnerability to infection, losing heat, difficulty breastfeeding).
You will learn about low birth weight babies in detail in the Postnatal Care Module.
- Malpresentation is more common in twin pregnancies, and they may also be ‘locked’ at the neck with one twin in the vertex presentation and the other in breech. The risks associated with malpresentations already described also apply: prolapsed cord, poor uterine contraction, prolonged or obstructed labour, postpartum haemorrhage, and fetal hypoxia and death.
- Conjoined twins (fused twins, joined at the head, chest, or abdomen, or through the back) may also rarely occur.