Is a first baby usually early or late?”
A due date is an average, and a lot of factors can affect it. One is a mom’s genetic heritage: a large British study found first babies of women of Asian or African ancestry more likely to be born in the week before a due date. On the other hand, a study of 14,000 Danish pregnancies found that the average spontaneous labor was 282 days from the first day of a woman’s last period, and babies of first-time moms averaged a 288-day gestation — a full eight days later than a due date based on a 40-week timetable would have predicted.
Your cycle length matters, too- the 40-week pregnancy timetable assumes a 28-day cycle with ovulation on the 14th day of the cycle, but if your cycle is longer or shorter then your pregnancy probably will be, too. You’re also more likely to deliver early if you’re having multiples, if you’re having a boy, or if you smoke. Given the strong genetic component of pregnancy length, though, your best bet is to ask your mom how long her pregnancies were- if hers were longer or shorter than usual, odds are yours will be, too.
Early or late?