July 1999, Vol. 33, No. 5

Despite an increasing population among Missouri teens, both the actual number of pregnancies and the rate of pregnancy are decreasing. Table 1 illustrates these opposing trends by age group. Birth and pregnancy rates amo ng females 15-19 will be the focus of this study.

Figure 1 illustrates the decline in pregnancy rates by the type of pregnancy outcome for females 15-19 from 1980 to 1998. Pregnancy rate includes the sum of induced abortions, fetal deaths, and live births divided by the number of females in a spec ified age group and is noted per 1,000 females. As mentioned in an earlier report1, teen pregnancies decreased from the early 1980s to the mid-1980s and then began increasing until 1991 when they began declining again. At the same time the number of femal es 15-19 declined throughout the 1980s and began increasing in 1993, a trend which continues.

Ventura et al.2 report that the birth rate for U. S. teenagers 15-17 years decreased 16 percent from 1991 - 1997 (1997 is the most current national data available) and the rate for teenagers 18-19 declined 11 percent. The overall national decrease was 14.8 percent from 62.1 births for teens age 15-19 per 1,000 females in 1991 to 52.9 in 1997. Missouri shows a larger decrease beginning with a higher birth rate for ages 15-19 (64.4) in 1991 and ending with a lower rate (51.5) in 1997 - a decrease of 20 percent. In addition 1998 data showing a birth rate of 51.2 indicate that the decline is continuing. By age group Missouri shows nearly a 24 percent drop among 15-17 year old teens from 1991-1997 (38.7 in 1991 to 29.6 in 1997) with a continued decline to 29.1 in 1998. As with the nation, the decrease is less among the older teens: 14 percent - from 100.3 in 1991 to 86.3 in 1997 with a continuing decrease to 83.8 in 1998.

Pregnancies to females under age 15 constitute less than two percent of all teen pregnancies. From 1991 to 1998, the pregnancy rate among 10-14 year olds dropped from 2.1 to 1.2 - a decline of 42 percent. In terms of events, this means a drop from close to 400 pregnancies per year to a little over 200 pregnancies per year. In addition, the proportion of all teen pregnancies occurring to the very youngest girls (under 15) has dropped from 2.5 percent to 1.8 percent.

The decline in birth rates is greatest among blacks both in the nation and in Missouri. Among teens 15-19 the birth rate for Missouri blacks decreased more than the national black rate from 145.3 in 1991 to 103.0 in 1997 - a 29 percent decline - co mpared to the national decrease of 23 percent2. Missouri and U. S. white teens 15-19 did not fare as well - experiencing only declines of 15 percent (U. S.) and 16 percent (Missouri). The Missouri birth rate for blacks 15-19, despite the decline remains h igher than the national rate (103.0 for Missouri vs. 89.5 for the U.S.). Figure 2 shows the trend in fertility by age and race of the mother. As with the nation, the largest decrease in birth rates occurred among 15-17 year old blacks with a decline of ne arly 25.6 percent in Missouri and 26 percent nationally. White teens aged 18-19 showed the smallest decline in birth rates dropping only 8.6 percent. Nevertheless, as Figure 2 illustrates, births occur more frequently among black teens than among white te ens so that the large decline among 15-17 year old blacks brings them down below the birth rate of 18-19 whites for the first time.

The percent of teen births occurring to teens who had a previous birth also decreased from 1991 to 1996 from 25.1 percent to 21.9 percent (U.S.) and from 25.8 percent to 20.9 percent (Missouri). In Missouri, 1997 continued this trend with 20.6 perc ent of all teen births occurring to teens with a previous birth. However, 1998 shows a slight increase (21.1) in repeat births particularly among whites (to 18.7 from a low of 17.5 in 1997).

Teen birth rates vary by geographic area as is indicated in Table 2. Although in 1991 the birth rate for urban Missouri3 was nearly equal to that of the rural area, by 1997 the birth rate for the urban area had dropped 24.2 percent compared to 11.5 percent for the rural area so that the urban rate was nearly 16 percent lower than the rural rate. During the same time, pregnancy rates dropped 1.7 times as much in urban Missouri as in rural Missouri (28.7 percent to 17.1 percent). Therefore, pregnancy rates are identical (nearly 65 per 1000 females 15-19), with abortion rates remaining higher in the urban area.

Nationally, pregnancy rates among females 15-19 are nearly double the birth rates2. In Missouri the relationship between pregnancy rates and birth rates are much closer because of the relatively low abortion rate (12.0 per 1,000 females in 1998). A bortion rates declined approximately 40 percent from 1991-1997 among Missouri teens 15-19. Births constitute 80 percent of all teen pregnancies in Missouri. Of these births, 79.6 percent are to unmarried mothers - up from 71 percent in 1991. The percent o f all teen births which are to unmarried mothers is highest among blacks and in the urban area but the biggest increase has been in the rural area - up from 54.9 percent in 1991 to 66.8 percent in 1997 (21.7 percent increase) and among whites - an increas e of 20.9 percent from 59.2 percent to 71.6 percent in 1997. The trend continues in 1998 with 69 percent of all rural teen births to unmarried mothers and 73 percent of all white teen births to unmarried mothers.

Teen pregnancy is down despite an increasing teenage population. Both births and abortions are declining in absolute numbers and rates. The biggest decreases are among younger teens, blacks and in the urban population. Ventura et al2, attribute the decline to a decrease in sexual activity among teenagers, the increased use of contraceptives among sexually active teens, and the use of injectable and implant contraceptives. Despite the overall favorable trend toward decreasing pregnancies among 15-19 year old teens, there are some less favorable trends that should be of concern. Births to unmarried mothers constitute a larger proportion of teen pregnancies (80 percent of the births and 64 percent of all pregnancies). The decrease in teen pregnancy is not as rapid in the rural population. In addition, the proportion of pregnancies resulting in births to unmarried mothers is increasing rapidly from 45 percent of teen pregnancies in 1991 to 61 percent in 1998. Therefore, despite the declines in both the birth and pregnancy rates, the number of teen births to unmarried mothers remains the same so that approximately 8,000 births in Missouri are born each year to unmarried females 15-19 years of age. In the rural area the number of births to unmarried teen mothers actually increased from 2,000 births in 1991 to over 2,500 births in 1998.

In summary:

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