 |
Multiple Births, 1980-2005
The rising incidence of multiple births over the last two decades has
been associated with two related trends: the older age at childbearing
(older mothers are more likely than younger mothers to conceive multiples
spontaneously) and increasing use of fertility therapies. A study of
multiples born in the year 2000 estimated that natural conception
accounted for 67% of the twins and only 18% of the triplets and greater
multiples born that year.
| |
1980 |
1985 |
1990 |
1995 |
2000 |
2001 |
2002 |
2003 |
2004 |
2005 |
|
Number of births:
|
|
|
|
|
|
|
|
|
|
|
| Twins |
68,339 |
77,102 |
93,865 |
96,736 |
118,916 |
121,246 |
125,134 |
128,665 |
132,219 |
133,122 |
| Triplets and higher multiples |
1,337 |
1,925 |
3,028 |
4,973 |
7,325 |
7,471 |
7,401 |
7,663 |
n.a. |
n.a. |
| Triplets |
n.a. |
n.a. |
2,830 |
4,551 |
6,742 |
6,885 |
6,898 |
7,110 |
6,750 |
6,208 |
| Quadruplets |
n.a. |
n.a. |
185 |
365 |
506 |
501 |
434 |
468 |
439 |
418 |
| Quintuplets and higher
multiples |
n.a. |
n.a. |
13 |
57 |
77 |
85 |
69 |
85 |
86 |
68 |
| |
|
|
|
|
|
|
|
|
|
|
|
Birth rate:
|
|
|
|
|
|
|
|
|
|
|
| Triplets (per 100,000 live births) |
136.1 |
158.4 |
175.5 |
170.3 |
166.1 |
171.0 |
171.5 |
173.8 |
164.2 |
150.0 |
| Quadruplet and higher multiples (per 100,000 live births) |
16.5 |
15.2 |
17.9 |
14.6 |
14.4 |
14.6 |
12.5 |
13.5 |
12.8 |
11.7 |
Source: National Center for Health Statistics, National Vital Statistics Reports, vol. 56, no. 6, Dec. 5, 2007. |
