The rate and associated features of stillbirth among eclamptic and preeclamptic women*

Giriş

This study was performed to determine the rate of stillbirth among hypertensive pregnant women and to do- cument the relation between stillbirth and various demographic, obstetric and laboratory parameters.

Yöntem

Forty-three hypertensive women were enrolled the study. Stillbirth was defined as those infants born at 20 we- eks gestation or later whose Apgar score was 0 at 1 and 5 minutes.

Bulgular

The rate of stillbirth was 18.6% among eclamptic and preeclamptic women. Gestational age was found signifi- cantly small in stillbirth group than live birth group (32.6±5.7 versus 36.9±3.3, p<0.05). The majority of stillbirth was iden- tified at the eclamptic women (62.5%, p<0.05) and hellp syndrome was associated to the clinic course in the half of the stillbirth cases. The stillbirth group had significantly higher mean values of conjugated fraction of bilirubin and total biliru- bin (p<0.01). There was only one case of intrapartum stillbirth among the 8 cases. None of the women had antenatal ca- re in the stillbirth group.

Sonuç

 Eclamptic women especially complicated by Hellp syndrome had had a greater risk of stillbirth when com- pared to preeclamptic women. The majority of stillbirth had occurred before admission to hospital. Sufficient antenatal ca- re seemed that the most important factor to decrease the rate of stillbirth.

Anahtar Kelimeler

Ölüdoğum, Eklampsi, Hellp sendromu, Antenatal takip

Giriş

Pregnancy-induced hypertension (PIH), an impor- tant cause for fetal death as well as maternal mor- bidity and mortality (1). Most of the studies in this fi- eld are about clinical management. There are few stu- dies on fetal outcome and most of these related to pe- rinatal mortality consist of stillbirths and neonatal de- aths. It is reported that the most important risk factors for stillbirth in PIH are midtrimester pregnancies and abruptio placenta and the rate 2-10% (2-4). Taking in- to account the different causal factors for stillbirth and
neonatal death we aimed at examining only the cha- racteristics of stillbirth in PIH.

Yöntem

This study was carried out at the Department of Gynecology and Obstetrics in Medical school in Yü- züncü Yıl University. Forty-three PIH cases treated and delivered between 1 January 1995 and 31 March 1996 were included in the study. Of total cases, 8 stillbirths and 35 live births consisted of study group and cont- rol group, respectively. Data regarding to type of PIH, sociodemographic, clinical, obstetric characteristics, and laboratory findings were collected as prospecti- vely. We defined fetal death as any birth at 20 weeks' gestation or greater with an Apgar score of 0 at 1 and 5 minutes. If the blood pressure was higher than 160/110 mmHg the PIH was classified as severe, ot- herwise as mild accompanied by either generalized edema or proteinuria (of at least 2 or more) on dips- tick examination. Unemployment and those who have no social security were accepted as poor socioecono- mic status. Antenatal care criterion was at least 1 visit in each trimester. An infant was considered as small- for gestational age (SGA) if the birth-weight was be- low the tenth percentile according to gestational we- eks (5). Hemolysis, elevated liver enzymes and low platelets (<100.000/mm3) were the criteria for Hellp syndrome. If the value of BUN and/or serum creatini- ne was twice higher than the normal, it was defined as "impaired renal function".
In our department, aggressive management is prac- ticed for eclampsia and Hellp syndrome, labor induc- tion was started as soon as the condition of woman gets stabile, regardless of taking account the gestation weeks. Expectant management is practiced in mild preeclampsia whereas aggressive approach is prefer- red in severe preeclampsia, above 32 weeks' gestati- on.
Statistical analyses, namely chi-square, student t test, Fisher's exact test and Mann Whitney-U test, we- re performed using SPSS for Windows packet program. The numeric parameters with unequal variance (p<0.05 on Levene test) such as BUN, ALT, AST, se- rum creatinine and bilirubin levels were analyzed using Mann Whitney-U test A p value <0.05 was signi- ficant.

Bulgular

During the study period, 228 deliveries and 22 still- births were observed. In all cases, stillbirth rate was 9.6%. Of 43 PIH cases, 8 were stillbirth and 35 live birth. Stillbirth rate was 18.6% in PIH cases. PIH-de- pendent stillbirth rate in the total stillbirths was 36.4%. The rate of PIH cases in the total deliveries was 18.9%.
The distribution of PIH types in all cases was given in first section of Table 1. While eclampsia was at high level (62.5%, p<0.05) in stillbirth group, mild preec- lampsia was not observed. The distribution of PIH types excluding Hellp syndrome cases was given in the second section of Table 1. With respect to PIH types, the significant difference was lost among the groups (p>0.05). Hellp syndrome which observed as approximately 10% in both mild and severe preec- lampsia consist of almost half of eclampsia cases (p<0.05, Table 2).
The evaluation of the various demographical and clinical characteristics was presented in Table 3- Whi- le mean gestational age at delivery was small in still- births than controls; maternal age, parity, blood pres- sure at admission and fetal birth weight were similar between two groups.
While in regard of socioeconomic status, antenatal care, antihypertensive treatment after the admission, generalized edema, proteinuria, impaired renal functi- on, low-birth-weight, SGA, fetal sex and mode of de- livery were similar, Hellp syndrome and prematurity were higher in stillbirths than live births (50% versus 14.3% and 25% versus 2.9%, respectively) (p<0.05, Table 4).
Laboratory findings were given in Table 5. Altho- ugh, average serum creatinine, ALT, AST, and BUN va- lues were higher and mean platelet number was lower in stillbirth group, the difference was not significant (p>0.05). On the other hand, mean values of uncon- jugated and conjugated bilirubin in stillbirth group were higher (p<0.01) than control group (2.5±2.6 ver- sus 0.6+0.3, and 0.8±0.6 versus 0.3±0.1, respectively).
Chronic hypertensive case or major fetal anomaly were not observed. However, only in one case abrup- tio placenta was determined and this case was in live birth group.

Tartışma

In this study, stillbirth rate was found very high (9.6%) for all deliveries. Of 22 stillbirth 8 (36.4%) was PIH-related which was four times higher than (9%) reported by Ahlineus et all (6). Similarly, stillbirth rate in PIH cases was higher than pervious reports (2-4). PIH- related stillbirth rate in severe preeclampsia-eclampsia was reported as 9% excluding one major fetal ano- maly (1). In our study, stillbirth rate for severe preec- lampsia-eclampsia cases was 33-3% when excluded mild PIH cases, both overall and PIH-related high still- birth rates could be explained by being our hospital as a reference center. In addition, low socioeconomic level and poor antenatal care may also be reason fin- ding high stillbirth rates. Of 43 PIH cases only 5 (11.6%) had antenatal care which was significantly lo- wer than the figure (82%) which reported by Sibai et al. (2). In the most of cases (87.5%), the fetal death was occurred before admission. This indicates the im- portance of antenatal care. Finding poor antenatal ca- re can not be explained by only lower socioeconomic level, because even one-fourth of women had lower socioeconomic level, almost none of them had ante- natal care. Maybe the main problems for that are illi- teracy and self-careless of woman.
There is a linear correlation between severity of PIH and fetal loss, high stillbirth rate was especially re- ported in Hellp syndrome and eclampsia cases (7-11). Similar to this we found that, sitllbirth rate was signi- ficantly higher in eclampsia than preeclampsia whereas no stillbirth was observed in mild preeclampsia (62.5% versus 37.5%, p<0.05, Table 1). On the other hand there is no significant difference among the PIH types for stillbirth when Hellp syndrome cases were excluded (p>0.05). In addition there was a linear cor- relation between associated Hellp syndrome and PIH types (table 2). Of 11 mild preeclampsia cases only in one, and of 13 eclampsia cases 6 Hellp syndrome was determined (p<0.05). Because of this findings we sug- gest that other than severity of PIH, associated Hellp syndrome may be main causative factor for stillbirth.
It was reported that stillbirth rate was 10% in hellp syndrome cases (4). In our study, this rate was found as 44.5% (table 4). The cause of high stillbirth rate in Hellp syndrome may be related to serious uteropla- cental insufficiency, and impaired hepatic and renal function. In this study, both conjugated and unconju- gated bilirubin levels in stillbirth group were observed high (p<0.01, Table 5). This finding is indicator of he- molysis and hepatocellular damage and shows the re- ason-result relation between Hellp syndrome and still- birth. In addition, BUN, ALTS, AST, and serum creati- nine values were also high in stillbirths group. Beca- use of, probably, high standard deviation due to hete- rogeneous distribution of values, differences among the groups were not significant statistically.
Hypertension is not effective on fetal survival alo- ne, associated severe proteinuria is also important for increased fetal loss (8,12). However, proteinuria may not be the only determinant factor for stillbirth accor- ding to Lin et al. (13). They performed postpartum re- nal biopsy in 157 hypertensive cases and higher still- birth rate was found in multiparous severe preeclamp- sia group compared to chronic glomerulonephritis group, although there was the same degree proteinu- ria in both groups. We also did not find any significant difference between two groups according to proteinu- ria (p>0.05, Table 4).
Gestational age is the most important indicator of fetal survival in PIH.Fetal survival is the bestobstetric above 36 weeks' gestation and the worst below 28 weeks (1,10,14). The primary reason for this si-
tuation is immaturity of fetal lung. In addition, theearlier starts the PIH the higher probalitiy of int-rauterine growth retardation, which decreases thefetal survival (1). We found that gestational age atdelivery was four weeks shorter in stillbirth group(p<0.05, Table 3). Even mild preeclampsia casespracticed expectant management were excluded,there was still a three-week shortness betweentwo groups. For this reason it could be said thatthe earlier starts the PIH the higher stillbirth rate.
Abruptio placenta and SGA are considered themajor reasons for stillbirth in PIH (1,15). But wedid not find significant differences between twogroups for both conditions.

Sonuç

As a summary, the major causative factors for still- birth in PIH in our population were severity of PIH (especially complicated by Hellp syndrome) and ear- lier weeks' gestation. So, in PIH cases special care at- tention should be given for liver and renal function screening tests. In order to get better fetal survival in PIH, prenatal care should be improved. In addition, early hospitalization, close follow-up with fetal surve- illance tests, and appropriate magnesium sulfate treat- ment are well known important issues for prevention of fetal loss.
As a summary, the major causative factors for still- birth in PIH in our population were severity of PIH (especially complicated by Hellp syndrome) and ear- lier weeks' gestation. So, in PIH cases special care at- tention should be given for liver and renal function screening tests. In order to get better fetal survival in PIH, prenatal care should be improved. In addition, early hospitalization, close follow-up with fetal surve- illance tests, and appropriate magnesium sulfate treat- ment are well known important issues for prevention of fetal loss.

 

Kaynaklar

1. Sibai BM, Spinnato JA, Watson DL, Hill GA, Anderson GD: Pregnancy Outcome in 303 Cases With Severe Preeclampsia. Obstet Gynecol, 64: 319-25, 1984.
2. Sibai BM, McCubbin JH, Anderson GD, Lipshitz J, Dilts PV Jr: Eclampsia. I. Observations from 67 recent cases. Obstet Gynecol, 58: 609-13, 1981.
3. Douglas KA, Redman CW: Eclampsia in the United Kingdom. BMJ, 309: 1395-400, 1994.
4. Eeltink CM, van Lingen RA, Aarnoudse JG, Derks JB, Okken A: Maternal haemolysis liver enzymes and low platelets syndrome: specific problems in the newborn. Eur J Pediatr, 152: 160-3, 1993.
5. Şener T, Atar Gürel S, Gürel H, Hassa H, Özalp S: Fetal gelişmenin değerlendirilmesinde kullanılan kendi popülasyonumuza ait doğum ağırlığı standart eğrileri. Zeynep Kamil Tıp Bülteni, 24: 230-6, 1992.
6. Ahlenius I, Floberg J, Thomassen P: Sixty-six cases of intrauterine fetal death: A prospective study with an extensive test protocol. Acta Obstet Gynecol Scand, 74: 109-17, 1995.
7. Swain S, Ojha KN, Prakash A, Bhatia BD: Maternal and perina- tal mortality due to eclampsia. Indian Pediatr, 30: 771-3, 1993.
8. Derham RJ, Hawkins DF, De Vries LS, Aber VR, Elder MG: Out- come of pregnancies complicated by severe hypertension and delivered before 34 weeks; stepwise logistic regression analysis of prognostic factors. Br J Obstet Gynaecol, 96:1173-81, 1989.
9. Sibai BM, Taslimi MM, el-Nazer A, Anion E, Mabie BC, Ryan CM: Maternal-perinatal outcome associated with the syndrome of hemolysis, elevated liver enzymes, and low platelets in seve- re preeclampsia-eclampsia. Am J Obstet Gynecol, 155-501-9, 1986.
10. railton A, Allen DG: Management and outcome of pregnancy complicated by severe pre-eclampsia of early onset. S Afr Med J, 72: 608-10, 1987.
11. Sibai BM, Abdella TN, Anderson GD: Pregnancy Outcome in 211 Patients With Mild Chronic Hypertension. Obstet Gynecol, 61:571-6, 1983.
12. Ferrazzani S, Caruso A, De Carolis S, Martino IV, Mancuso S: Proteinuria and outcome of 444 pregnancies complicated by hypertension. Am J Obstet Gynecol, 162: 366-71, 1990.
13.Lin CC, Lindheimer MD, River P, Moawad AH: Fetal outcome in hypertensive disorders of pregnancy. Am J Obstet Gynecol, 142: 255-60, 1982.
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	Dosya / Açıklama
	Tablo 1. The distribution of pregnancy-induced hypertension types
	Tablo 2 The distribution of Hellp syndromes among PIH types
	Tablo 3 The distribution of various demographic and clinical characteristics between stillbirths and live births in PIH cases
	Tablo 4 The distribution of various sociodemographic, bestobstetric and clinical characteristics between stillbirths and live births.
	Tablo 5 Laboratory findigs.