How is twin pregnancy different?

Women expecting twins may experience increased pregnancy symptoms such as nausea, fatigue, or swelling. While it's not quite accurate to say that these symptoms are doubled in a twin pregnancy, the increased hormone levels do aggravate symptoms in some cases.

A woman expecting twins is also at risk of certain complications, such as preterm labour, pregnancy-induced hypertension (PIH) and gestational diabetes. Expecting mothers should take proper medical care, follow a healthy diet, have a lot of fluids and minimise any activity that puts their pregnancy at risk. One of the most common rules of a twin pregnancy is "Rest, Rest and more Rest".

Preterm delivery is common in twin gestation; only 15 percent of twin pregnancies complete 36 weeks of pregnancy. The incidence of Caesarean sections is higher because of malposition, low placenta and intrauterine growth restrictions. Twins may be delivered vaginally, if the first twin is in the head-down position.

Twin types: The correct term for defining twin type is zygosity, which describes whether the twins are from a single fertilised egg (monozygotic or identical twins) or several eggs or zygotes (dizygotic, multizygotic or fraternal). Monozygotic twins share the majority of their DNA, and exhibit obvious similarities.

Gender lines: Monozygotic twins are always of the same sex, unless there's a genetic disorder such as Turner's Syndrome. Dizygotic twins can be either of the same sex or one of each.