WIC Participation and Pregnancy Outcomes: Massachusetts Statewide Evaluation Project

Article (PDF Available)inAmerican Journal of Public Health 74(10):1086-92 · November 1984with40 Reads
DOI: 10.2105/AJPH.74.10.1086 · Source: PubMed
Abstract
The effects of WIC prenatal participation were examined using data from the Massachusetts Birth and Death Registry. The birth outcomes of 4,126 pregnant women who participated in the WIC program and gave birth in 1978 were compared to those of 4,126 women individually matched on maternal age, race, parity, education, and marital status who did not participate in WIC. WIC prenatal participants are at greater demographic risk for poor pregnancy outcomes compare to all women in the same community. WIC participation is associated with improved pregnancy outcomes, including, a decrease in low birthweight (LBW) incidence (6.9 per cent vs 8.7 per cent) and neonatal mortality (12 vs 35 deaths), an increase in gestational age (40.0 vs 39.7 weeks), and a reduction in inadequate prenatal care (3.8 per cent vs 7.0 per cent). Stratification by demographic subpopulations indicates that subpopulations at higher risk (teenage, unmarried, and Hispanic origin women) have more enhanced pregnancy outcomes associated with WIC participation. Stratification by duration of participation indicates that increased participation is associated with enhanced pregnancy outcomes. While these findings suggest that birth outcome differences are a function of WIC participation, other factors which might distinguish between the two groups could also serve as the basis for alternative explanations.
WIC
Participation
and
Pregnancy
Outcomes:
Massachusetts
Statewide
Evaluation
Project
MILTON
KOTELCHUCK,
PHD,
MPH,
JANET
B.
SCHWARTZ,
MS,
RD,
MARLENE
T.
ANDERKA,
MPH,
AND
KARL
S.
FINISON,
MA
Abstract:
The
effects
of
WIC
prenatal
participation
were
exam-
ined
using
data
from
the
Massachusetts
Birth
and
Death
Registry.
The
birth
outcomes
of
4,126
pregnant
women
who
participated
in
the
WIC
program
and
gave
birth
in
1978
were
compared
to
those
of
4,126
women
individually
matched
on
maternal
age,
race,
parity,
education,
and
marital
status
who
did
not
participate
in
WIC.
WIC
prenatal
participants
are
at
greater
demographic
risk
for
poor
pregnancy
outcomes
compare
to
all
women
in
the
same
community.
WIC
participation
is
associated
with
improved
pregnancy
outcomes,
including,
a
decrease
in
low
birthweight
(LBW)
incidence
(6.9
per
cent
vs
8.7
per
cent)
and
neonatal
mortality
(12
vs
35
deaths),
an
Introduction
Efforts
to
improve
the
health
status
of
pregnant
women
and
their
young
children
through
nutritional
supplementa-
tion
and
education
have
long
been
a
part
of
public
health
programs
in
the
United
States.
The
Special
Supplemental
Food
Program
for
Women,
Infants
and
Children
(WIC),
established
in
1972,
is
the
largest
and
most
specifically
targeted
public
health
nutrition
program
in
the
United
States
today.
The
WIC
program
is
designed
to
reach
high-risk
pregnant
and
lactating
women,
infants,
and
children
up
to
5
years
of
age
with
supplemental
foods
and
nutrition
educa-
tion,
as
an
adjunct
to
good
health
care.'
WIC
is
the
first
federal
nutrition
program
to
use
identifi-
able
nutritional
risk,
in
addition
to
low
income,
as
a
criterion
for
eligibility.
Since
its
inception,
WIC
has
grown
to
provide
benefits
to
2.9
million
persons
monthly,
at
a
cost
of
$1.36
billion
in
fiscal
year
1983.
An
estimated
500,000
pregnant
women
now
participate
in
the
WIC
program.
Eligible
participants
receive
a
monthly
set
of
food
vouchers
redeemable
at
local
grocers
for
specific
foods
tailored
to
individual
needs.
Allowable
foods
include:
milk,
cheese,
iron-fortified
cereal,
100%
fruit
juices,
eggs,
dried
beans,
peanut
butter,
and
iron-fortified
formula
for
infants.
The
cost
of
the
food
package
is
approximately
$30
per
month,
provided
at
no
cost
to
the
participants.
Nutrition
education
is
also
provided.
A
more
complete
description
of
the
WIC
program
appears
elsewhere.2
The
WIC
program,
despite
its
magnitude
and
its
clearly
stated
public
health
goals,
has
not
been
extensively
exam-
ined.
The
lack
of
research
may
be
the
result
of
a
moral
acceptance
of
the
virtues
of
feeding
high-risk
women
or
of
the
methodological
difficulties
of
conducting
quality
re-
search
in
a
large,
decentralized
nutrition
program.
The
latter
include
the
difficulty
of
obtaining
a
proper
comparison
sample,
the
lack
of
data
collected
uniformly
across
program
sites,
and
the
need
for
large
sample
sizes
to
show
stable
From
the
Division
of
Family
Health
Services,
Massachusetts
Department
of
Public
Health.
Address
reprint
requests
to
Milton
Kotelchuck,
PhD,
MPH,
Department
of
Social
Medicine
and
Health
Policy,
Harvard
Medical
School,
25
Shattuck
Street,
Boston,
MA
02115.
This
paper,
submitted
to
the
Journal
June
27,
1983,
was
revised
and
accepted
for
publication
March
21,
1984.
Editor's
Note:
See
also
Different
Views,
pp
1145-1149
this
issue.
C
1984
American
Journal
of
Public
Health
0090-0036/84
$1.50
increase
in
gestational
age
(40.0
vs
39.7
weeks),
and
a
reduction
in
inadequate
prenatal
care
(3.8
per
cent
vs
7.0
per
cent).
Stratification
by
demographic
subpopulations
indicates
that
subpopulations
at
higher
risk
(teenage,
unmarried,
and
Hispanic
origin
women)
have
more
enhanced
pregnancy
outcomes
associated
with
WIC
participa-
tion.
Stratification
by
duration
of
participation
indicates
that
in-
creased
participation
is
associated
with
enhanced
pregnancy
out-
comes.
While
these
findings
suggest
that
birth
outcome
differences
are
a
function
of
WIC
participation,
other
factors
which
might
distinguish
between
the
two
groups
could
also
serve
as
the
basis
for
alternative
explanations.
(Am
J
Public
Health
1984;
74:1086-1092.)
program
effects.
To
date,
only
two
evaluations
of
prenatal
participation
in
WIC
based
on
perinatal
outcomes
have
been
published.
Despite
quite
divergent
methodologies,
Edozien,
et
al,3
and
Kennedy,
et
al,4
both
reported
that
WIC
partici-
pation
is
positively
associated
with
maternal
weight
gain,
infant
birthweight,
and
gestational
age,
and
that
the
WIC
programs'
effectiveness
is
enhanced
by
increasing
duration
of
participation.
Others
maintain
that
the
value
of
WIC
is
unproven.5
This
paper
reports
the
results
of
the
Massachusetts
WIC
Statewide
Evaluation
Project,
which
examined
the
associa-
tion
between
maternal
participation
in
the
WIC
Program
in
1978
and
the
outcomes
of
pregnancy.
Specifically,
four
questions
were
addressed:
*
Does
the
WIC
Program
reach
its
target
population?
*
Is
WIC
participation
associated
with
more
positive
outcomes
of
pregnancy?
*
Are
the
effects
of
WIC
participation
similar
across
all
high-risk
subpopulations?
*
Are
the
effects
of
the
WIC
program
enhanced
with
increased
duration
of
participation?
The
Massachusetts
WIC
Program
The
Massachusetts
WIC
program
is
similar
to
WIC
programs
nationally.
In
1978,
it
operated
through
23
non-
profit
local
health
centers
and
social
service
agencies
under
contract
with
the
State
Department
of
Public
Health.
Ap-
proximately
22,000
persons
participated
monthly,
of
whom
over
4,000
were
pregnant
women.
At
the
time
of
the
study,
geographic
eligibility,
in
addition
to
income
guidelines
and
nutritional
risk,
was
a
criterion
for
WIC
participation.
In
Massachusetts,
the
issuance
and
redemption
of
all
WIC
food
vouchers
is
centrally
monitored
through
a
single
computerized
bank
control
system.
This
system
allows
for
an
accurate
documentation
of
the
names,
duration
of
partici-
pation,
and
number
of
vouchers
redeemed
for
all
prenatal
WIC
participants.
Methodology
Study
Population
The
basic
design
of
the
study
is
a
direct
comparison
of
the
pregnancy
outcomes
of
two
groups
of
Massachusetts
women
who
gave
birth
in
1978:
those
who
participated
in
the
WIC
prenatal
program,
and
a
matched
control
group
of
non-
WIC
women.
The
derivation
of
the
study
population
and
AJPH
October
1984,
Vol.
74,
No.
10
1086
WIC
PARTICIPATION,
PREGNANCY
OUTCOME:
MASSACHUSETTS
TABLE
1-Selected
Maternal
Demographic
Characteristics,
1978:
WIC
Participants,
Catchment
Area
Resi-
dents
and
All
Massachusetts
Residents
%
WIC
%
Catchment
%
All
Massachusetts
%
WIC
Saturation
Characteristics
Participants
Area
Residents
Residents
of
Catchment
Area
Age
s17
years
12.2
6.0
3.8
36.4
l19
years
28.6
16.9
11.5
30.4
Education
-9
years
14.9
10.5
5.1
25.4
<12
years
49.2
31.5
19.0
28.0
Mantal
Status
Unmarried
40.7
23.9
13.7
30.6
Married
59.3
76.1
86.3
14.0
Race
Black
23.8
16.0
6.2
27.0
White
73.6 81.6
91.8
16.2
Parity
1
44.9 45.9
44.6
17.6
5+
6.5
4.1
3.3
28.4
TOTAL
(N)
(4,126)
(22,995)
(67,187)
study
data
results
from
the
linkage
of
two
computerized
data
systems:
the
WIC
bank
voucher
system,
and
the
State
Birth
and
Death
Registry.
Appendix
A
summarizes
the
three
steps
were
involved.*
First,
the
names
of
all
women
who
registered
as
a
WIC
prenatal
participant
were
drawn
from
the
WIC
computerized
participant
voucher
reports
(N
=
4,898).
Data
on
the
dura-
tion
and
number
of
vouchers
cashed
per
month
were
also
extracted.
Failure
to
pick
up
vouchers
for
two
consecutive
months
resulted
in
administrative
termination
from
the
pro-
gram.
Administrative
termination
codes
were
noted
on
525
names.
Specific
causes
for
termination
were
known
for
172
of
the
names,
while
353
names
remained
unaccounted
for.
As
this
was
a
study of
women
who
actively
participated
in
WIC,
all
525
women
with
termination
codes
were
excluded
from
the
study,
leaving
4,373
eligible
participants.
Second,
each
mother's
name
(plus
town
of
residence,
race,
and
expected
date
of
delivery)
obtained
from
the
WIC
reports
was
linked,
by
hand,
to
the
corresponding
infant's
birth
certificate
record
listed
in
the
state's
computerized
Birth
Registry
file.
Twin
births
(46)
and
know
fetal
deaths
(15)
were
excluded,
as
were
191
names
which
could
not
be
positively
linked.
Third,
each
WIC
participant
was
individually
matched
to
a
control
subject
on
the
basis
of
five