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... thepopulation.Thenumberofwomen
sherepresentsinthepopulationiscalled
hersamplingweight.Sampling
weightsmayvaryconsiderablyfromthis
averagevaluedependingonthe
respondentsrace,theresponseratefor
similarwomen,andotherfactors.As
withanysamplesurvey,theestimatesin
thisreportaresubjecttosampling
variability.SignicancetestsonNSFG
datashouldbedonetakingthesampling
designintoaccount.
Nonsamplingerrorswereminimized
bystringentquality-controlprocedures
thatincludedthoroughinterviewer
training,checkingtheconsistencyof
answersduringandaftertheinterview,
imputingmissingdata,andadjustingthe
samplingweightsfornonresponseand
undercoveragetomatchnationaltotals.
Estimatesofsamplingerrorsandother
statisticalaspectsofthesurveyare
describedinmoredetailinanother
separatereport(13).
Thisreportshowsndingsby
characteristicsofthewomaninterviewed,
includingherage,maritalstatus,
education,parity,householdincome
dividedbythepovertylevel,andraceand
Hispanicorigin.Ithasbeenshownthat
blackandHispanicwomenhavemarkedly
lowerlevelsofincome,education,and
accesstohealthcareandhealthinsurance,
thanwhitewomen(14).Theseandother
factors,ratherthanraceororiginperse,
probablyaccountfordifferencesinthe
behaviorsandoutcomesstudiedinthis
reportamongwhite,black,andHispanic
women(15).
TableBshowsafactorthatshould
beconsideredininterpretingtrendsin
pregnancy-relatedbehaviorintheUnited
States:thechangingagecompositionof
thereproductive-agepopulation.In
1982,therewere54.1millionwomenof
reproductiveageintheUnitedStates;in
1988,57.9million;andin1995,60.2
million(16).Thelargebabyboom
cohort,bornbetween1946and1964,
was1834yearsofagein1982,2442
yearsofagein1988,and3149years
ofagein1995.Theselargebirthcohorts
werepreceded(upto1945)and
followed(196580)bysmallercohorts.
Whiletheoverallnumberofwomen
1544yearsofageroseby6million,or
11percentbetween1982and1995,the
numberofteenagewomendroppedby
about6percent,thenumberofwomen
2024yearsofagedroppedby
15percent,andthenumberofwomen
2529droppedby6percent(tableB).In
contrast,thenumberofwomen3044
yearsofageincreasedsharplyfor
example,thenumberofwomen4044
yearsofageincreasedby59percent
between1982and1995.Also,women
3044yearsofageaccountedfor
54percentofwomen1544yearsofage
in1995comparedwith44percentin
1982.Thesedifferencesinage
compositionmayberelevantwhenever
timetrendsamongwomen1544years
ofagearebeingdiscussed.
Publicuselesbasedonthe1995
NSFGareavailableoncomputertape.
TheywillalsobeavailableonCompact
DiscRead-OnlyMemory(CD-ROM).
Questionsaboutthecostandavailability
ofthecomputertapesshouldbedirected
totheNationalTechnicalInformation
Service(NTIS),5285PortRoyalRoad,
Springeld,VA22161,703487-4650,
or1800-553-NTIS.Questionsregarding
theCD-ROMlesshouldbedirectedto
NCHSDataDisseminationBranchat
301436-8500.
Results
T
ables117containmeasuresof
pregnancyandbirthintheUnited
States.
ChildrenEverBornandTotal
BirthsExpected
In1995,women1544yearsof
ageintheUnitedStateshadhadan
averageof1.2birthsperwoman
(table1).Thiscompareswith1.2in
1988and1.3in1982(17).In1995,
women1544yearsofageexpectedto
nishtheirchildbearingwithan
averageof2.2childrenperwoman
(table1)comparedwith2.2in1988
and2.4in1982(17).
Theproportionwhoreportthatthey
haveneverbeenpregnantwasmarkedly
higherforcollegegraduatesthanfor
thosewhodidnotcompletehighschool
(table3).Thissamepatternbyeducation
isalsoseenwhendataforlivebirthsare
examined(tables45):about49percent
ofwomen2244yearsofagewhohad
graduatedfromcollegehadhadnolive
birthsasofthedateofinterview
comparedwithjust8percentofwomen
2244yearsofagewithoutahigh
schooldiploma(table4).Withinrace
andHispanicorigingroups,thepattern
wasthesame:collegegraduateshad
markedlyhigherpercentschildlessthan
womenwithlesseducation(table5).
Table6showsacomparison
betweenlivebirthsreportedinthe
NSFGandlivebirthsregisteredonbirth
certicatesintheyears199194.In
eachindividualcalendaryearandfor
thesumoftheyears199194,the
NSFGestimateofthenumberofbirths
isveryclosetothebirthcerticatetotal
anddiffersfromitbylessthanthe
NSFGssamplingerror.TheNSFG
estimateisalsoverycloseforwhite
women.TheNSFGestimateforblack
womenisslightlylower,andthe
estimateforotherracessomewhat
higherthanthebirthcerticatedata.A
discussionofthisdifferenceisgivenin
thedenitionofRaceandHispanic
originintheDenitionsofTerms.
Overall,andbycharacteristicsother
thanrace,however,table6showsthat
TableB.Numberofwomen,byage:UnitedStates,1982,1988,and1995
Ageơ ... thepopulation.Thenumberofwomen
sherepresentsinthepopulationiscalled
hersamplingweight.Sampling
weightsmayvaryconsiderablyfromthis
averagevaluedependingonthe
respondentsrace,theresponseratefor
similarwomen,andotherfactors.As
withanysamplesurvey,theestimatesin
thisreportaresubjecttosampling
variability.SignicancetestsonNSFG
datashouldbedonetakingthesampling
designintoaccount.
Nonsamplingerrorswereminimized
bystringentquality-controlprocedures
thatincludedthoroughinterviewer
training,checkingtheconsistencyof
answersduringandaftertheinterview,
imputingmissingdata,andadjustingthe
samplingweightsfornonresponseand
undercoveragetomatchnationaltotals.
Estimatesofsamplingerrorsandother
statisticalaspectsofthesurveyare
describedinmoredetailinanother
separatereport(13).
Thisreportshowsndingsby
characteristicsofthewomaninterviewed,
includingherage,maritalstatus,
education,parity,householdincome
dividedbythepovertylevel,andraceand
Hispanicorigin.Ithasbeenshownthat
blackandHispanicwomenhavemarkedly
lowerlevelsofincome,education,and
accesstohealthcareandhealthinsurance,
thanwhitewomen(14).Theseandother
factors,ratherthanraceororiginperse,
probablyaccountfordifferencesinthe
behaviorsandoutcomesstudiedinthis
reportamongwhite,black,andHispanic
women(15).
TableBshowsafactorthatshould
beconsideredininterpretingtrendsin
pregnancy-relatedbehaviorintheUnited
States:thechangingagecompositionof
thereproductive-agepopulation.In
1982,therewere54.1millionwomenof
reproductiveageintheUnitedStates;in
1988,57.9million;andin1995,60.2
million(16).Thelargebabyboom
cohort,bornbetween1946and1964,
was1834yearsofagein1982,2442
yearsofagein1988,and3149years
ofagein1995.Theselargebirthcohorts
werepreceded(upto1945)and
followed(196580)bysmallercohorts.
Whiletheoverallnumberofwomen
1544yearsofageroseby6million,or
11percentbetween1982and1995,the
numberofteenagewomendroppedby
about6percent,thenumberofwomen
2024yearsofagedroppedby
15percent,andthenumberofwomen
2529droppedby6percent(tableB).In
contrast,thenumberofwomen3044
yearsofageincreasedsharplyfor
example,thenumberofwomen4044
yearsofageincreasedby59percent
between1982and1995.Also,women
3044yearsofageaccountedfor
54percentofwomen1544yearsofage
in1995comparedwith44percentin
1982.Thesedifferencesinage
compositionmayberelevantwhenever
timetrendsamongwomen1544years
ofagearebeingdiscussed.
Publicuselesbasedonthe1995
NSFGareavailableoncomputertape.
TheywillalsobeavailableonCompact
DiscRead-OnlyMemory(CD-ROM).
Questionsaboutthecostandavailability
ofthecomputertapesshouldbedirected
totheNationalTechnicalInformation
Service(NTIS),5285PortRoyalRoad,
Springeld,VA22161,703487-4650,
or1800-553-NTIS.Questionsregarding
theCD-ROMlesshouldbedirectedto
NCHSDataDisseminationBranchat
301436-8500.
Results
T
ables117containmeasuresof
pregnancyandbirthintheUnited
States.
ChildrenEverBornandTotal
BirthsExpected
In1995,women1544yearsof
ageintheUnitedStateshadhadan
averageof1.2birthsperwoman
(table1).Thiscompareswith1.2in
1988and1.3in1982(17).In1995,
women1544yearsofageexpectedto
nishtheirchildbearingwithan
averageof2.2childrenperwoman
(table1)comparedwith2.2in1988
and2.4in1982(17).
Theproportionwhoreportthatthey
haveneverbeenpregnantwasmarkedly
higherforcollegegraduatesthanfor
thosewhodidnotcompletehighschool
(table3).Thissamepatternbyeducation
isalsoseenwhendataforlivebirthsare
examined(tables45):about49percent
ofwomen2244yearsofagewhohad
graduatedfromcollegehadhadnolive
birthsasofthedateofinterview
comparedwithjust8percentofwomen
2244yearsofagewithoutahigh
schooldiploma(table4).Withinrace
andHispanicorigingroups,thepattern
wasthesame:collegegraduateshad
markedlyhigherpercentschildlessthan
womenwithlesseducation(table5).
Table6showsacomparison
betweenlivebirthsreportedinthe
NSFGandlivebirthsregisteredonbirth
certicatesintheyears199194.In
eachindividualcalendaryearandfor
thesumoftheyears199194,the
NSFGestimateofthenumberofbirths
isveryclosetothebirthcerticatetotal
anddiffersfromitbylessthanthe
NSFGssamplingerror.TheNSFG
estimateisalsoverycloseforwhite
women.TheNSFGestimateforblack
womenisslightlylower,andthe
estimateforotherracessomewhat
higherthanthebirthcerticatedata.A
discussionofthisdifferenceisgivenin
thedenitionofRaceandHispanic
originintheDenitionsofTerms.
Overall,andbycharacteristicsother
thanrace,however,table6showsthat
TableB.Numberofwomen,byage:UnitedStates,1982,1988,and1995
Ageơ ... for Child Health and Human
Development, and the Office of
Population Affairs, with additional
support from the Administration for
Children and Families—all of the U.S.
Department of Health and...