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Reproductive Health
Data
definitions, limitations & uses • Data Sources
Births and
Fertility
In Leeds, Grenville and Lanark (LGL), the
population has increased significantly in
the past 20 years. This increase has been
the result of two factors: net births and
net immigration. Births are affected by both
individual and social factors. These can
include the health and socio-economic status
of potential parents, as well as existing
social and health policies. All pregnancies
and births carry some health risks for the
mother and the child. Risks are higher in
mothers that have health problems. Mothers
are also at higher risk of complication if
pregnancies: come too early, come too late
in a woman’s reproductive life, are too
closely spaced, or are unwanted. In this
section of the report live
births, age-specific
fertility rates, teenage
pregnancy, therapeutic
abortions, low-birth
weight, and stillbirths
and congenital anomalies will be
discussed.
Live births
In Leeds, Grenville and Lanark (LGL), the
number of live births increased steadily
between1981 and 1992. The number peaked in
1992 at 2088 live births and has been
falling ever since. In 1996, the number of
births had fallen to 1705, which is a rate
of 1.8 live births per woman of childbearing
age. This is the smallest number of births
in the region since the early 1980's (see figure 1).
In LGL, the crude fertility rate, which had
been stable during most of the late 1980s
and early 1990s, began to decrease rapidly
in 1992 (see
figure 2). Compared to Ontario,
fertility rates had been higher in LGL every
year between 1981 and 1996. However, as the
fertility rate decreased in LGL, rates in
Ontario have remained more stable. As
result, these rates have begun to converge.
Historically in Canada, most babies were
born to women in there 20’s. This has also
been true in LGL. Between 1981 and 1985 in
LGL, 69.4% of live births were born to women
between 20-29 years of age. In the past 10
years, within this age group women are
giving birth at older ages. The result has
been that over time the percent of women
between 25-29 giving birth has increased,
while the percent of women 20-24 giving
birth has decreased. For example, in LGL,
between 1981 and 1985, 30.2% of all live
births were to women 20-24 years of age, yet
this percent had fallen in the years between
1991-1996, when only 22.6% of all live
births were to women 20-24 years of age.
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Age-specific
fertility rates
The age-specific fertility rate is defined
as the number of live births occurring for
every 1000 women in a specific age category
during a specified period of time. In LGL,
in 1996, the age-specific fertility rate was
highest among 25-29 year old women, with a
fertility rate of 135.6 live births per 1000
women. Despite the increasing percent of all
live births to women in this age group, the
age-specific fertility rate is essentially
the same as it was in 1981, 137.7 live
births per 1000 women.
In general, the age-specific fertility rates
among women in LGL have remained very stable
between 1981 and 1996. However, one
significant change is that, since 1994, the
age-specific fertility rates for women 30-34
years old have surpassed those for 20-24
year olds in LGL. In 1996, there were 71.4
live births per 1000 to women 20-24 years
old in LGL and 81.1 live births per 1000 to
women 30-34. (see figure 3)
In Ontario the trends are more clear. The
age-specific fertility rates for women 35-39
and 30-34 have been increasing while the
rates for women 20-24 and 25-29 have been
decreasing (see
figure 4) .
Teen Pregnancy
Pregnancy before age 20 entails a number of
medical risks for both the mother and her
child. Teenage mothers are at greater risk
of having a pre-term baby or a baby with an
immediately identifiable congenital
abnormality. Teenagers also have a slightly
higher risk of having low birth weight
infants. Furthermore, the social and
economic consequences of teenage births are
as important as the health implications. For
example, teenage motherhood may result in a
loss of educational and occupational
opportunities and may also increase the
likelihood of diminished socio-economic
status. Compared with older women who give
birth, teenagers are more likely to be
single, and therefore, to be financially
dependent on family support and social
assistance.
In 1995 there were 167 teenage pregnancies
in Leeds, Grenville and Lanark (LGL). This
produced a rate of 34.3 pregnancies per 1000
women15-19 years of age. This rate is much
lower than the teenage pregnancy rate for
all of Ontario, which was 47 pregnancies per
1000 women 15-19 years of age in 1995(see figure 5).
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Therapeutic Abortions
In Leeds, Grenville and Lanark (LGL), the
total number of abortions decreased from 298
in 1992 to 216 in 1995. This is the smallest
number of abortions reported for any year
between 1992 and 1995. The abortion rate
fell in LGL from 9.4 abortions per 1000
women between 15-49 years of age in 1993, to
5.5 abortions per 1000 women in the same age
group in 1995. This rate was much lower than
the abortion rate in Ontario in the same
year, which was approximately 19 abortions
per 1000 women in the same age group.
In general, abortions are most common among
women in their early childbearing years.
Almost sixty percent of all abortions
performed in LGL between 1992 and 1995 were
to women between 15 and 24 years of age (see figure 5a). Among
younger women, a greater percentage of women
who had abortions were single. For example,
in 1994, 94% of women under 25 who had had
an abortion were single. This differs from
women 25 and older, where only 42% of those
that had had an abortion were single.
Age-specific abortion rates
Between 1992 and 1995 the age-specific
abortion rates in LGL have been highest
among women 15-19 years old and lowest in
women over 30. In this time period, rates
among 15-19 year olds and 20-24 year olds
fell dramatically (see
figure 6). In
every year between 1992 and 1994 the
age-specific abortion rate among 15-19 year
olds was between 15 and 20 abortions per
1000 women. However in 1995 there was a
significant decrease in the abortion rate in
these women, as the rate fell from 19.9
abortions per 1000 women in 1994 to 9.4
abortions per 1000 women in 1995 (96
abortions in 1994 to 46 in 1995 in this age
group).
Low Birth Weight
(less than 2500 grams)
An infant’s weight at birth is one of the
main determinants of its survival and
healthy growth and development. Low birth
weight can lead to mental and physical
disabilities and other negative health
outcomes. In most cases, low birth weight is
the result of either premature birth, lack
of inutero nourishment or heavy maternal
smoking. Because of its importance,
reduction of the prevalence of low birth
weight, is one of the objectives of the
Ontario Ministry of Health’s, Mandatory
Health Programs and Services Guidelines. The
objective set by the Ministry is to reduce
the low birth weight rate (under 2500g) to 4
per cent by the year 2010. From our current
levels, the low birth weight rate would have
to be reduced by .13% per year to reach a
low birth weight rate of 4.0 by the year
2010.
In Leeds, Grenville and Lanark (LGL), 5.3%
of all live births in 1996 were low birth
weight babies. This was a reduction of 1.4%
from 6.7% of all live births in 1995. This
is the lowest the rate has been since 1991,
when 5.1% of all live births in LGL were of
low weight (see
figure 7) . In Ontario, the percent of
low birth weight babies was 6.1% of all live
births in 1996.
The type of birth, influences an infants
birth weight. For example, a very large
proportion of twins and triplets are born
low birth weight infants. In LGL, between
1981 and 1996 a little more than 50% of all
twin live births were low birth weight
children (see
figure 8). Similarly, 77% of triplets
were low birth weight children. Since 1981,
twins, triplets, and quadruplets accounted
for 2% of all live births in LGL. However,
since 1992 the number of live births has
decreased while the proportion of these live
births that were multiple births has
increased. This is important because there
does appear to be a relationship between the
multiple birth rate and the low birth rate
in LGL. The two rates are co-related (r-.64
(.o5> p>.01). This relationship is a
directly proportional relationship. This
means that as the multiple birth rate
increases so too does the low birth weight
rate. The multiple birth rate is a
proportion. It is the proportion of all live
births that are multiple births. (see figure 9).
In LGL, between 1990 and 1996, the low
birth weight rate varied with the age of the
birth mother. Women at the extremes of
reproductive age (15-19) and (45-49) had the
highest low birth weight rates. Among 15-19
year old the low birth weight rate was 8.1
while it was 40.00 among women 45-49.
However, together these two age groups
accounted for less than10% of all low birth
weight babies in LGL between 1990-1996. In
total 61% of low birth weight babies were
born to women 25-34 years old. This occurred
even though the lowest age-specific low
birth rate (4.6 percent) was observed among
25-29 year olds.
The low birth weight rate in LGL also varies
with marital status. In 1996, single women
had a low birth weight rate of 6.9% of all
live births, whereas married women in that
same year had a low birth weight rate of
5.3%. Between 1981 and 1996, the low birth
weight rate among single women had decreased
steadily from a low birth weight rate of
8.9% in 1981 to a low birth weight rate of
6.9% in 1996. Among married women the low
birth weight rate has remained stable since
1981 (between 5.0% and 5.4%).
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Stillbirths and Congenital
Anomalies
The stillbirth rate is the number of
stillbirths occurring in a given time period
divided by the total number of births
(stillbirths and livebirths) in that time
period *1000.
Due to the fact that there were very few
stillbirths annually in Leeds, Grenville and
Lanark (LGL), the stillbirth rate is
calculated for three time periods, 81-85,
86-90 and 92-96. In doing so, this makes the
rates more stable. In LGL, between 1992 and
1996, the rate of stillbirths was 6.5 per
1000 total births. This is similar to the
Ontario rate (see
table). Between 1992 and 1996,
stillbirths occurred primarily among women
25-29 years of age, accounting for 37% of
all stillbirths. Furthermore, almost all
stillbirths in this period occurred to women
under 35 years of age, accounting for 85% of
all stillbirths.
Between 1992 and 1994, the crude congenital
anomalies rate in LGL (350.4 cases of
congenital anomalies, per year, per 10,000
total births) was slightly lower than the
rate for Ontario (366.7 cases of congenital
anomalies, per year, per 10,000 total
births). Between 1992 and1994, the highest
rates of congenital anomalies occurred for
Hypospadias, Epispadias, Downs syndrome,
Cleft lip and palate, and Hydrocephalus (see table). For most
types of anomalies the rates in Ontario,
between 1992 and 1994, were similar to those
observed in LGL.
The rate of neural tube defects in LGL was
similar to that of Ontario. That is, the
rate was 22.4 neural tube defects, per year,
per 10,000 total births in Ontario, compared
to 21.8 neural tube defects, per year, per
10,000 total births in LGL (see figure
10) . One of the objectives listed in
Mandatory Health Programs and Services
Guidelines is to decrease the prevalence of
neural tube defects by 25% by the year 2010.
In LGL this would mean that our target for
the year 2010 should be a neural tube
defects rate of 16.8 neural tube defects per
10,000 total births.
Data definitions,
limitations & uses
Crude fertility rate
Age-Specific Fertility Rate
Low birth weight rate
Age-Specific therapeutic abortions rate
Rate of multiple births
Stillbirths Rate
Teenage Pregnancy Rate
Rate of Neural Tube Defects
Data Sources
Congenital Anomalies Database
Live births Database
Therapeutic Abortions Database
Ontario Still Birth Datbase
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