Monaco: 

Pregnant Angelina Jolie seen taking her two daughters, Zahara and Shiloh, shopping for baby clothes, in Monaco, in May 2008. She gave birth to twins last week

Hollywood's hottest couple, Angelina Jolie and Brad Pitt became proud parents once again on July 12, as Angie gave birth to twins Knox and Vivienne. Their last child, Shiloh was born two years ago.

Not spacing out your deliveries can put the mother at risk of anaemia and her child at risk of IUGR, a form of growth retardation say gynaecologists.

"It is better to recover from one pregnancy and childbirth before embarking on the next. There is a slightly higher risk of prematurity and low birth weight in babies conceived within six months of a previous birth," says consultant gynaecologist Dr Nandita Palshetkar.

What you gain by keeping a gap

The advantages of a larger gap between kids includes having extra time to recover your energy, having the opportunity to enjoy each child as an individual, helps give him/her your undivided attention for the first few years. It also spreads bringing up a baby's cost, over a longer period of time.

Don't overdo it

However, children who are more widely spaced may grow up to have a "generation gap" between each other. "There can be clashes of opinion and a sense of distance, because the siblings are in different phases of their lives," says child psychiatrist Dr Zirak Marker.

Marker says there is no right age difference that is most appropriate for family planning. The elder sibling is a social partner, and role model for behaviour, speech and language development.

Siblings learn to care, share and play with each other. They also help in educational development of the younger kids. When the age difference is lesser, sibling rivalry is the only major shortcoming. Yet, it's normal among all children unless it turns violent and intense.

Tiff between siblings

Sometimes, there is resentment from the older child who feels his/her position has been usurped by a new arrival. Also, women starting their families well into their 30s, may not have the luxury of choosing wider gaps as diminishing fertility becomes a factor.

However, Colombian researchers have found that an interval of less than 18 months and more than 59 months  just under five years increases health risks for children.