When the weather gets cold and the nights draw in, there isn’t always a great deal to do beyond getting an early night.
This may be the factor behind claims that recent colder winters have contributed to a boom in the birthrate.
‘Some believe that the fertility rate was highest in September, October and November in 2010 because people were staying in more due to the bad weather the previous winter,’ a spokesman for the Office for National Statistics said.
Their figures show a winter baby boom has pushed up birth rates to levels not seen for nearly 40 years.
The number of women giving birth during the late months of the year has shot up by a fifth in a decade–faster than the increase during the summer.
Autumn births have been particularly high over the past two years, according to the analysis.
The months in 2010 with the highest fertility rates–the number of children for every woman of childbearing age–were September, at 2.11; October, at 2.09; and November, at 2.03. The lowest fertility rates were in April and May, with 1.92 and 1.93 for each woman.
The fertility rate is a figure that expresses how many children the average woman is likely to have over her lifetime.
It is worked out by dividing the birth rate in a particular period by the number of women of childbearing age.
This means that a spike in births will raise the rate for a particular month.
In October, the month last year with the greatest number of births, there were 64,542 newborns, an increase of nearly 27 per cent over the same month in 2000.
By contrast, the 54,551 children born in the month with the lowest births figure in 2010, February, was a 16 per cent rise over the same month in 2000.
Babies born during the autumn of last year were conceived during one of the coldest winters for years and January 2009 was the coldest since 1997.
Birth rates are now higher than at any point since the early 1970s and, as a result, the average woman can now expect to have at least two children.
Reasons for the baby boom so far advanced by state statisticians include childbearing by large numbers of women in their 30s and 40s having children late, and immigration, which has brought three million into the country since 1997.