Outcomes of 17137 Pregnancies in2 Urban Areas of Ukraine

Ruth E. Little, ScD, Susan C. Monaghan, DrPH, Beth C. Gladen, PhD,Zoreslava A. Shkyryak-Nyzhnyk, MD, and Allen J. Wilcox, MD, PhD

There is evidence of a decline in publichealth in the countries of central and easternEurope since the dissolution of the SovietUnion. Maternal and infant health are report-edly compromised by frequent, repeated ter-minations of pregnancy; high rates of fetalloss; and increased infant morbidity and mor-tality.2 This information is drawn largely fromofficial and unofficial statistics that may beincomplete or biased; the true extent of risk isdifficult to assess.

To explore the state of reproductivehealth in this region, we conducted a study in2 urban areas of Ukraine, a newly indepen-dent country that was part of the formerSoviet Union. There have been anecdotal

M$R.'' reports of higher rates of reproductive prob-lems and infant mortality in Ukraine, but

.... there has been no systematic investigation ofthem to our knowledge. Here we describe theresults of a population-based investigation ofclinically recognized pregnancies and theiroutcomes.

Methods

We conducted a census of all pregnan-cies diagnosed in 2 study sites during a 19-month period. The study sites were the LeftBank (Dniprovski) region, one of 14 districtsin the capital city of Kyiv (Kiev), and the cityof Dniprodzerzhinsk, approximately 400 kmsoutheast of Kyiv. Both sites had about aquarter of a million inhabitants in 1993.3They vary in demographic, economic, andecological conditions, but both are highlyindustrialized urban areas.

These sites were chosen for the censusbecause they are part of the area where theEuropean Longitudinal Study of Pregnancyand Childhoods ("Longitudinal Study") isbeing conducted in Ukraine. This ongoingstudy attempts to enroll every woman who isseen for prenatal care in a targeted geo-

graphic area and who is expected to deliverduring a specified time period. However, inUkraine, women who did not plan to con-tinue their pregnancy or who did not meetother criteria, primarily related to permanentresidence in the area, were excluded. Ourcensus defined a 19-month eligibility periodthat was the same as the Longitudinal Studycohort eligibility range (most recent men-strual period occurring between February 25,1992, and July 23, 1994) to provide a popula-tion-based description of pregnancy out-comes at the 2 sites.

Enumeration Procedures

The clinically diagnosed pregnancies inthe sites were divided into those that wereended by elective termination and those thatwere not ("continuing pregnancies"). Thecentralized nature of the Ukrainian healthcare system facilitated ascertainment ofthesepregnancies. All public medical care inUkraine was provided at no charge during thestudy period, and there was virtually no pri-vate medical care. Women were assigned to ahealth care facility on the basis of their resi-dence; services included prenatal care at thelocal polyclinic and delivery at the local hos-pital unless the case was complicated.

Ruth E. Little, Beth C. Gladen, and Allen J. Wilcoxare with the National Institute of EnvironmentalHealth Sciences, Research Triangle Park, NC.Susan C. Monaghan is with the School of PublicHealth, University of Illinois, Chicago. ZoreslavaA. Shkyryak-Nyzhnyk is with the Institute of Pedi-atrics, Obstetrics, and Gynecology, Kyiv, Ukraine.

Requests for reprints should be sent to Ruth E.Little, ScD, Epidemiology Branch, A3-05, NationalInstitute of Environmental Health Sciences, PO Box12233, Research Triangle Park, NC 27709 (e-mail:little I (niehs.nih.gov).

This article was accepted June 3, 1999.

December 1999, Vol. 89, No. 12

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Ukrainian Pregnancies

Elective termination was legal, free, andaccessible through 12 weeks' gestation. Termi-nations after this point were allowed for med-ical reasons or for social reasons, such asdivorce or partner's death during the pregnancy,if a senior obstetrician-gynecologist approved.Ifa woman sought termination at another facil-ity, she was required to obtain special docu-ments from the local clinic and to undergo testsso that a record ofthe termination existed there.Illegal terminations were probably uncommonsince early termination was readily available.

Several steps were taken to maximizeascertainment. At both sites, lists of eligiblepregnancies were prepared by a single physi-cian from clinic termination logs and medicalrecords. We checked within and across lists todetect duplicates and serial pregnancies of thesame woman by matching last name, date ofbirth, and date of delivery. We searched manu-ally and by computer for other similar names.We stratified both termination and continuingpregnancy lists by month of most recent men-strual period to check for omission of recordsand to confirm that women on the lists fellwithin the period of study.

Difficulty in locating delivery records isthe most likely source of error in the enumer-ation. The archives of the hospitals were dif-ficult to access. There is no microfilm inUkraine, nor is the location of records com-puterized, so locating original documents wasan arduous process. Floods occurred in thearchives ofboth sites during the study period.One archive was relocated, and another wasclosed. Because of these difficulties, wecompiled 2 separate and independent inven-tories of all available hospital records, severalmonths apart.

Variables

The following information was col-lected for the pregnancies at the 2 sites: studysite, mother's name and date of birth, mostrecent menstrual period or estimated date ofconception, pregnancy outcome, date of ter-mination-delivery, and gestational age at ter-mination-delivery (for some terminations,date or gestational age, but not both, waslisted). Pregnancy outcome and gestationalage at which it occurred were the primaryvariables in this study.

Outcome ofpregnancy. For continuingpregnancies, a live birth was defined, accord-ing to World Health Organization (WHO)criteria, as one in which "the fetus is expelledor extracted from the mother, regardless ofthe duration of pregnancy, after which thechild breathes or shows any other sign of life,such as heartbeat, pulsation of the umbilicalcord, or voluntary muscular movement."6Because this was not the customary defini-

tion of live birth in Ukraine, we monitoredadherence to the WHO definitions by clini-cians and record abstractors throughout theduration ofthe study.

Several checks were made to increasethe accuracy of the outcome data. When thewoman was not a Longitudinal Study partici-pant, we attempted to determine the missingoutcome by returning to the medical recordsand contacting the woman. If the woman wasa Longitudinal Study participant, additionalinformation was available from the studyrecords. In every case of a reported adverseoutcome, the medical record was reviewed toconfirm the loss and the gestational age atwhich it occurred and to verify that the losswas spontaneous.

Gestational age. In continuing pregnan-cies, gestational length was calculated asnumber of completed weeks from mostrecent menstrual period to date of delivery.Most recent menstrual period was deter-mined by the woman's report during her firstvisit to the Women's Consultation Clinic. Ifno data on most recent menstrual period wereavailable in the record, estimates were madeaccording to a systematic protocol that incor-porated gestational information from allavailable sources. Date of delivery and a clin-ical gestational age estimate made after thebirth were derived from an abstract of thepregnancy outcome that was sent to the ante-natal clinic by the hospital. For terminationsbefore 13 weeks, gestational age was takenfrom the clinic records or from estimateddate of conception established by physicalexamination.

There was concern that some of thewomen might have misstated the timing oftheir most recent menstrual period to gainpregnancy benefits, which are increased withlonger gestation. Therefore, in continuingpregnancies, gestational age estimates basedon most recent menstrual period were checkedagainst the hospital's clinical estimates; weexpected that clinical estimates of gestationswould be shorter than estimates based onmost recent menstrual period if this bias werepresent. We compared these 2 values inwomen who were Longitudinal Study partici-pants, because there were multiple sources ofinformation available that could help toresolve discrepancies.

Gestational age was grouped into 7 cate-gories. Ninety percent of the LongitudinalStudy subjects had a category ofclinical gesta-tion that was closer to term (38-42 weeks)than the category based on the most recentmenstrual period estimate. Among womenwho were not Longitudinal Study participants,the same tendency of the clinic estimate ofgestation to be closer to term than the mostrecent menstrual period estimate was seen;

this tendency has been reported by others.7Fewer than 3% of clinical estimates of gesta-tional age were more than one categoryremoved from the most recent menstrualperiod estimate. There was no evidence thatwomen routinely reported a most recent men-strual period that was earlier than its actualdate; therefore, this estimate was the basis forgestational age in the present study. Gesta-tional age data based on most recent menstrualperiod were available for 96% of continuedpregnancies.

Substudy on Complete Ascertainment ofOutcome

After delivery of all registered pregnan-cies, outcome data were still missing for 353potential cases. While this represents only2% of all clinically diagnosed pregnancies,mortality rates are based on relatively fewnumbers of deaths and thus can changesharply with the omission ofjust a few sub-jects. We were concerned that women withmissing outcomes might have had high-riskpregnancies with an increased probability ofdeath. Therefore, we conducted a substudy todetermine the reasons for missing outcomes.

In 145 cases, we found that the womenhad moved or obtained prenatal care inanother area. The move was the probable rea-son for the missing outcome, because the dis-tance between facilities limited communica-tion. It was unlikely that these pregnancieswere particularly high risk. From the remain-ing 208 pregnancies, we chose a sample of48 women stratified by most recent men-strual period. These 48 women were thefocus of intensive follow-up efforts, whileroutine efforts to determine outcomes for theremaining cases continued. The intensivefollow-up revealed that 19 of the 48 miss-ing outcomes were due to duplicate identity,an error usually caused by hyphenated orchanged names or by misspelling. This find-ing led us to search for and eliminate otherpossible cases of double counting in thelarger study.

Another 13 women either had neverbeen pregnant or had most recent menstrualperiod estimates outside the boundaries ofthe study. Thus, the 48 missing outcomesyielded only 16 eligible pregnancies. In 4 ofthese 16 cases, the women had moved out ofthe area, 7 had delivered live births, one hadhad a spontaneous abortion at 17 weeks, andanother had had a spontaneous abortionat an unknown gestation. The remaining3 women could not be located, even via per-sonal visit to their home. We infer fromthese results that the missing outcomes inthis population are not necessarily those ofhigh-risk women whose pregnancies would

American Journal of Public Health 1833December 1999, Vol. 89, No. 12

Little et al.

involve substantially increased probabilitiesof fetal death.

Results

During the period under study, 17 137pregnancies were registered in the target area:

5189 in Kyiv and 11948 in Dniprodzerzhinsk.Sixty percent (n = 10363) ended in inducedabortion; all but 102 of these terminationsoccurred during the first 12 weeks of gesta-tion. Terminations were more frequent in Dni-prodzerzhinsk (63%) than in Kyiv (54%).

Among the remaining 6774 ongoingpregnancies, matemal age at most recent men-strual period ranged from 13 to 45 years;

nearly one fifth ofthe women were 18 years or

younger (Table 1). Half of the women withknown gestation at their first visit began pre-

natal care in the first trimester, and an addi-tional 41% were seen by the end of the secondtrimester. Only 1% of the women had theirfirst visit for prenatal care after 36 weeks(Table 1).

Data on gestational age, plurality, andvital status at birth are shown in Table 2. Aftercompletion of all follow-up efforts, gesta-tional age was unknown for 264 deliveries,and outcome was unknown for 253. (Amongthe 253 pregnancies with missing outcomes,165 mothers had moved or received care

elsewhere; records of the remaining 88 cases

could not be located.) Twins were reported in32 of the births with known outcome; no

other multiple births were reported. Two per-

cent of the pregnancies in Kyiv and 6% ofthepregnancies in Dniprodzerzhinsk endedbetween the first prenatal visit and 20 weeks;these pregnancies are not included in furtheranalyses, nor are cases with unknown out-come or gestation.

There were 6172 pregnancies of at least20 weeks with known gestation and outcome(Table 2). These pregnancies produced 6199infants; 9.1% of them were born before37 weeks (Table 3). The fetal mortality rate at20 weeks and beyond was 29 per 1000; thisrate was nearly twice as high in Dniprod-zerzhinsk as in Kyiv. Among pregnancies of28 weeks or more, the fetal mortality rateswere 10 and 9 per 1000 births, respectively.

The US Bureau of the Census definesperinatal mortality using either all births of atleast 20 weeks or all births of at least28 weeks as the denominator and stillbirthscombined with deaths in the first 7 days oflifeas the numerator. We calculated perinatalmortality using the 20-week denominator.Discharge records indicated that 47 live-bominfants of at least 20 weeks' gestation diedbefore leaving the hospital. Exact age at deathwas known for 24 ofthem, and 20 died within

the first 7 days of life. Age at death was

unknown for the remaining 23, all of whomwere nonparticipants in the LongitudinalStudy. If we extrapolate the known results tothese 23 infants, 39 infants are estimated tohave died in the first week of life. Combin-ing the 39 postnatal deaths with the 179 fetal

deaths of at least 20 weeks' gestation (Table 3)yields 218 perinatal deaths, with an estimatedperinatal mortality rate of35.2 per 1000 birthsof at least 20 weeks. If none of the cases ofunknown age at death involved death in theperinatal period, the perinatal mortality ratewould be 32.1 per 1000; if all ofthem did, the

1834 American Journal of Public Health

TABLE 1-Age of Mother at Most Recent Menstrual Period and Gestational Ageat First Prenatal Visit, by City: Ukraine, 1992-1994

Dniprodzerzhinsk, Kyiv, Total,No. (%) No. (%) No. (%)

Mother's age, y13-18 883 (21) 363 (15) 1246 (19)19-30 2939 (69) 1689 (72) 4628 (70)31-35 335 (8) 210 (9) 545 (8)36+ 115(3) 86(4) 201 (3)Unknown 126 28 154

Gestation at first visit, wk2-12 2213 (55) 956 (41) 3169 (50)13-27 1519 (38) 1079 (47) 2598 (41)28-36 242 (6) 236 (10) 478 (8)37+ 35 (1) 36 (2) 71 (1)Unknown 389 69 458

Total 4398 2376 6774

Note. Data represent continuing pregnancies only.

TABLE 2-Reported Outcomes of Continuing Pregnancies, by Gestational Ageand City: Ukraine, 1992-1994

Singleton, Singleton, Twins, Both Twins, Both UnknownAlive Dead Alivea Deada Status Total

DniprodzerzhinskGestation, wk<20 0 263 0 0 3 26620-27 6 95 0 1 0 10228-36 254 18 7 0 6 28537-42 3383 20 10 0 8 342143+ 179 1 0 0 2 182Unknown 8 8 3 1 122 142

Total 3830 405 20 2 141 4398Kyiv

Gestation, wk<20 0 55 0 0 0 5520-27 5 23 0 0 0 2828-36 129 13 4 0 0 14637-42 1901 7 5 0 1 191443+ 111 0 0 0 0 111Unknown 6 4 1 0 i11 122

Total 2152 102 10 0 112 2376Total

Gestation, wk<20 0 318 0 0 3 32120-27 1 1 118 0 1 0 13028-36 383 31 11 0 6 43137-42 5284 27 15 0 9 533543+ 290 1 0 0 2 293Unknown 14 12 4 1 233 264

Total 5982 507 30 2 253 6774

aNo set of twins involved one stillborn.

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Ukrainian Pregnancies

rate would be 35.8 per 1000. With the28-week restriction, the perinatal mortalityrate is 16.0 per 1000 births when the extrap-olated rate for unknown deaths is used. Therate decreases to 12.7 ifwe assume that noneof the deaths involving an unknown dateoccurred in the first 7 days of life.

Discussion

We conducted a census of all pregnan-cies diagnosed in 2 urban areas of Ukraineduring a 19-month period between 1992 and1994. A total of 17137 women were seen attheir local clinics and diagnosed as pregnant.Sixty percent of the women chose to termi-nate their pregnancy. Among the pregnanciesthat continued to 20 weeks for which vitalstatus at delivery was known, the fetal mor-tality rate was 29 per 1000 infants. Whendeaths occurring in the first week of life wereincluded, estimated perinatal mortality was

between 32 and 36 per 1000 infants.

These results are not directly compara-

ble to official Ukrainian statistics in the studyperiod. WHO definitions of live birth andfetal death were not employed in Ukraineuntil 1996. Before this time, Soviet vital sta-tistics classified a delivery at less than28 weeks, at less than 1000 g, or with a

length of less than 35 cm as an "abortion"unless the infant survived 7 days.8 Ourresults can be compared with vital statisticsfrom the United States, however, becauseboth involved WHO definitions; the mostrecent available year is 1992. The US com-

parison group was White women, becausethe Ukrainian study population was almostexclusively White.

The most notable difference in the USand Ukrainian birth outcomes is the 5-foldgreater frequency of fetal deaths in Ukraine(Table 4). This differential reflects not onlythe higher rate of fetal deaths in every gesta-tional age category but the higher proportionof deliveries before 28 weeks, when only 8%of Ukrainian infants were born alive. This is

consistent with official Ukrainian statistics.When Ukraine is compared with 15 otherformer eastern bloc countries that use similardefinitions, only Russia routinely exceedsUkrainian fetal death rates.3

The perinatal mortality rate for infantsof 20+ weeks' gestation is at least 32.1 per

1000 births in Ukraine, in comparison with9.7 per 1000 for White US births. The highfetal death rate at lower gestations drives thisdifferential. Our inability to ascertain a pre-

cise number of postpartum infant deathsmakes it difficult to determine how the laterdeaths contribute to the rate; in any case, theextent of this contribution is small relative tofetal mortality. Inadequate resources for han-dling complications of delivery and limitedfacilities for high-risk newborn care may

contribute to mortality. Limited resources

and facilities are especially prevalent in Dni-prodzerzhinsk, which is far from the capitalcity of Kyiv and has less advanced technol-ogy and fewer resources in general.

In a study of 142 US infants born at 22to 25 weeks of gestation, 92% were live born(vs 8% of Ukrainian infants born at theseweeks of gestation), and 39% survived for atleast 6 months.9 The high perinatal deathrate in Ukraine is consistent with standardsof practice from the Ministry of Health,which does not mandate attempts to resusci-tate before 28 weeks.4 Failure to resuscitatecannot explain the higher fetal death rates,however, because intervention would besuccessful only if the death occurred in theminutes before birth.

We cannot say why the perinatal mor-

tality rate in the Ukrainian study populationis so high. Prenatal care was available earlyand without cost, but this has not been a sig-nificant contributor to better pregnancy out-comes in the United States.' 0 Maternal agemay be a factor; the Ukrainian study popula-tion contained a large proportion of womenyounger than 19 years. Of the countries ofthe former eastern bloc, only Bulgaria has a

larger proportion of teenaged mothers.2 Inthis study, the fetal mortality rate amongUkrainian women younger than 19 years was41 per 1000. However, fetal mortality was 25per 1000 even among women aged 19 to35 years, so young mothers account for a

small part of the total mortality of 29 per1000. The difference in fetal mortalitybetween the 2 census sites partially reflectsthe greater proportion of young women inDniprodzerzhinsk, but the mortality dispar-ity exists even if they are excluded.

The twin rate in the census is less thanhalf ofpublished rates in comparable popula-tions. A review of earlier international twinstudies indicates that twinning rates in the

former eastern bloc European countries have

American Journal of Public Health 1835

TABLE 3-Infant Vital Status and Fetal Mortality Rates, by Gestational AgeCategory and City: Ukraine, 1992-1994

Alive at Dead at Fetal MortalityBirth Birth Total Ratea

DniprodzerzhinskGestational age, wk20-24 0 72 72 1.00025-27 6 25 31 0.80628-31 36 5 41 0.12232-36 232 13 245 0.05337-42 3403 20 3423 0.00643+ 179 1 180 0.006

Total>20 weeks 3856 136 3992 0.034.28 weeks 3850 39 3889 0.010

KyivGestational age, wk20-24 4 16 20 0.80025-27 1 7 8 0.87528-31 22 4 26 0.15432-36 115 9 124 0.07337-42 1911 7 1918 0.00443+ 111 0 111 0.000

Total.20 weeks 2164 43 2207 0.019.28 weeks 2159 20 2179 0.009

TotalGestational age, wk20-24 4 88 92 0.95725-27 7 32 39 0.82128-31 58 9 67 0.13432-36 347 22 367 0.06037-42 5314 27 5341 0.00543+ 290 1 291 0.003

Total.20 weeks 6020 179 6199 0.029>28 weeks 6009 59 6068 0.100

Note. Data represent only continuing pregnancies with known gestation and vital status.aNumber of deaths divided by total births in category.

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Little et al.

TABLE 4-Gestational Age Distribution and Fetal Mortality Rates for Deliveriesin 2 Urban Areas of Ukraine and for Deliveries to White Mothers inthe United States, 1992

Ukraine United States, 1992Gestational Infants in Fetal Mortality Infants in Fetal MortalityPeriod, Wk Category, % Ratea Category, % Ratea

20-27 2.1 0.916 0.7 0.33928-36 7.0 0.071 8.8 0.021.37 90.9 0.005 90.5 0.002

All births 100.0 0.029 100.0 0.006

Note. Data represent continuing pregnancies. US computations are based on data forWhites from Vital Statistics of the U.S. 1992. For Ukraine, percentages are based on alldeliveries with known gestation of 20+ weeks and known vital status.

aNumber of deaths divided by total births in category.

historically been between 1% and 3%.11There is a time trend toward lower propor-tions of twins, but the figure in the Ukrainiancensus is so low that other factors are proba-bly at work.

To check on the possibility of missedtwins, we looked at data on the LongitudinalStudy participants. Study staffconducted peri-odic audits ofhospital records to identify theirsubjects who had delivered, and medicalrecords were abstracted for them; thus, it wasunlikely that many Longitudinal Study twindeliveries at local hospitals were missing fromthe census. The twin rate for LongitudinalStudy women was 0.0072. This is nearly triplethe rate for women not involved in the study(0.0025). The Longitudinal Study rate is closerto published rates but is still low. The discrep-ancy between expected and observed twinrates is probably due to other influences inaddition to underreporting, such as the highproportion of younger mothers in the censusand their lower observed rate oftwinming."

Finally, the termination rate in theUkrainian census mirrors the use of volun-tary abortion as the major method of birthcontrol in the former eastern bloc.'2 In thecensus study sites, the rate was 172 per 100live births, which is slightly higher than theofficial Ukrainian rate of 154 per 100. Thisnational rate was in the upper third of therates of all former eastern bloc countries in1993.3 In the United States, the terminationrate among Whites was estimated at 30 per100 live births in 1992.13

To our knowledge, the present study isthe first to useWHO definitions and rigorousresearch procedures to enumerate and reportpregnancy outcomes in an area of the formereastern bloc. The study involves some limita-tions, however. We could not enumerate preg-

nancies that were not clinically recorded,such as early spontaneous abortions and lateillegal terminations. The difficulty in access-ing records probably led to other pregnanciesbeing missed. None of these omissionsappeared to be a major source of bias, butthey should be kept in mind.

Furthermore, the urban areas where thestudy was conducted are not necessarily rep-resentative of the country or of the otherEuropean countries formerly in the easternbloc. The women residing in these areas,however, face the same problems as otherswho are in a period of transition from a cen-tralized system. Poverty, stress, high crimerates, pollution, and an underfunded healthcare system are characteristic of this transi-tion, and these are some of the factors thatmay interfere with reproduction.'4 The pres-ent study provides information on fetal healthin these difficult circumstances. D

ContributorsR. E. Little planned and supervised the study, analyzedthe data, and wrote the paper. S. C. Monaghan super-vised the Ukrainian fieldwork. She and Z. A. Shky-ryak-Nyzhnyk supervised the European LongitudinalStudy of Pregnancy and Childhood in Ukraine, whichinvolved subjects in the population described in thispaper; both assisted in writing the paper. B. C. Gladenassisted in designing the study, anabling the data, andwriting the paper. A. J. Wilcox assisted in the studydesign and contributed to writing the paper.

AcknowledgmentsThis study was conducted in collaboration with theongoing European Longitudinal Study of Pregnancyand Childhood, initiated by the World Health Orga-nization, coordinated through the University of Bris-tol in England, and conducted in Ukraine by the

Ukrainian Institute of Pediatrics, Obstetrics, andGynecology in cooperation with the University ofIllinois School of Public Health. Informed consentofparticipants was obtained by procedures approvedby the institutional review boards of these institu-tions, as well as the institutional review board of theNational Institute ofEnvironmental Health Sciences.

This work is dedicated to the memory ofLouise Hamilton Khmara, project officer of the Uni-versity of Illinois Data Center in Kyiv. It would nothave been possible without her.

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