Spontaneous Prematurity Research Articles

Histologic evidence of old intrauterine bleeding is more frequent in prematurity

OBJECTIVE: Our purpose was to study the incidence and location of histologic evidence of intrauterine bleeding in preterm and term placentas. STUDY DESIGN: A total of 462 consecutive placentas delivered at <32 weeks' gestation, from which cases of placenta previa, stillbirth, and multiple gestation were excluded, were compared with 108 consecutive term placentas (with similar exclusion criteria) in regard to the presence of hemosiderin in decidua of basal plate or placental membranes. Of the 462 preterm cases, 448 charts made specific reference to the presence or absence of vaginal bleeding. Bloody show alone was not considered bleeding. The blinded scoring of lesions (including acute ascending infection, uteroplacental vascular pathologic processes and related ischemic damage, chronic inflammation, and coagulation related lesions) was analyzed by contingency tables ( p < 0.05 significant). RESULTS: A total of 196 of 462 (43%) preterm placentas had any decidual hemosiderin compared with one of 108 (0.8%) at term ( p < 0.00001). Among the preterm cases, hemosiderin was significantly more common in preeclampsia ( 45 76 , 60%) and in cases clinically diagnosed as nonhypertensive abruptio placentae ( 21 33 , 64%) than in premature membrane rupture ( 72 192 , 37.5%) and preterm labor ( 58 161 , 36%, p < 0.003 ). The incidence of placental lesions in preterm cases with extraplacental membrane hemosiderin was not different than it was in cases without hemosiderin. Placental lesions related to basal-plate decidual hemosiderin in the preterm cases were villous infarct ( p < 0.0001), uteroplacental vessels with absence of phsyiologic change ( p < 0.003) and increased numbers of circulating nucleated erythrocytes ( p < 0.0007), uteroplacental thrombosis ( p < 0.0001), and villous fibrosis ( p < 0.0001) and hypovascularity ( p < 0.0001). Among the preterm cases, 23 of 48 (48%) with first-trimester bleeding, 33 of 66 (50%) with second-trimester bleeding, and 31 of 64 (48%) with multiple episodes of bleeding had decidual hemosiderni ( p < 0.0001). A clnical history of gestational bleeding was significantly less common in cases of preterm preeclampsia with histologic evidence of bleeding (four of 73, 5.5%) than in nonhypertensive abruptio placentae ( 18 31 , 58%), premature rupture of membranes ( 52 183 , 28%), or preterm labor ( 31 161 , 19%, p < 0.0001 ). Hemosiderin was not related to clinical bleeding <72 hours of delivery ( p > 0.20). CONCLUSIONS: Decidual bleeding is common in all clinical types of preterm birth and is most common in preterm preeclampsia and nonhypertensive abruptio placentae. A clnical history of bleeding is not correlated with the presence of decidual hemosiderin. Bleeding in the basal plate is related to histologic evidence of chronic uteroplacental vascular pathologic processes, which in cases of spontaneous prematurity (premature rupture of membranes, preterm labor, nonhypertensive abruption placentae) may be associated with decidual bleeding which occasionally may be clinically manifested as gestational bleeding.

Prediction of spontaneous prematurity based on prior obstetric outcome: [formula omitted], R Goldenberg, A Moawad, P Meis, J Iams, R Copper x, A Das x, E Thom x, F Johnson x, D McNellis, and the NICHD MFMU Network, Bethesda, MD

Prediction of spontaneous prematurity based on prior obstetric outcome: [formula omitted], R Goldenberg, A Moawad, P Meis, J Iams, R Copper x, A Das x, E Thom x, F Johnson x, D McNellis, and the NICHD MFMU Network, Bethesda, MD

Transplacental pharmacokinetics of the antituberculosis drugs.

Information concerning passage of the antituberculosis drugs across the human placenta is sparse and scattered throughout the medical literature. Little mention was made of this subject in recent reviews of the clinical pharmacokinetics of these agents (Holdiness 1984, 1985a). However, a detailed survey indicates 6 of the 12 compounds commonly used have documented transplacental passage in humans (table I). If pregnancy occurs during the treatment of tuberculosis, the risk to the developing fetus must be considered in advising the expectant mother and her obstetrician. The indications for chemotherapy and the basic principles of management of the pregnant women with active tuberculosis are essentially no different from those in the non-pregnant patient (Snider 1984). Therapy with 2 drugs is instituted at standard doses, and the duration of treatment should not be altered by the patient's pregnancy. Retrospective studies by Snider et al. (1980) have revealed a reasonable margin of safety for isoniazid, rifampicin, and ethambutol when utilised during pregnancy; questionable results have precluded the administration of streptomycin. From their research of the literature, these authors showed that 94% of all gestations terminated in delivery of apparently normal term infants. In utero exposure of fetuses to antituberculosis therapy revealed 2.8% with classified birth defects. It was suggested that with the exception of women on streptomycin, the risk of adverse gestational outcomes is no greater among pregnant women on antituberculosis regimens than among healthy pregnant females. Caution must be exercised when considering the teratogenic effects of these drugs as spontaneous abortions, stillbirths, birth defects and prematurity are common even in normal pregnancy. The possible teratogenic effects of this class of antibiotics in animal models and humans have recently been reviewed (Holdiness 1987a) and the reader is referred to this article. Snider (1984) indicated that preventive therapy should be given during the second and third trimesters of pregnancy to selected patients at high risk of development of progressive disease. Treatment should be instituted promptly when a tuberculous infection is detected. Preferred regimens are isoniazid-ethambutol, isoniazid-rifampicin, or isoniazid-ethambutol-rifampicin, although other drugs may be needed if the disease is recurrent or if there is resistance to these primary drugs.

Fetal chromosome analysis: screening for chromosome disease?

The aim of the study was to investigate the rationale of the current indications for fetal chromosome analysis. 5372 women had 5423 amniocentesis performed, this group constituting a consecutive sample at the chromosome laboratory, Rigshospitalet, Copenhagen from March 1973 to September 1980 (Group A + B). Pregnant women 35 years of age, women who previously had a chromosomally abnormal child, families with translocation carriers or other heritable chromosomal disease, families where the father was 50 years or more and women in families with a history of Down's syndrome (group A), were compared to women having amniocentesis, although considered not to have any increased risk of fetal chromosome abnormality (1390 pregnancies, group B). They were also compared with 750 consecutive pregnancies in women 25-34 years of age, in whom all heritable diseases were excluded (group C). The risk of unbalanced chromosome abnormality in group A (women with elevated risk) is significantly higher than in group B + C (women without elevated risk) (relative risk 2.4). Women with a known familial translocation and women 40 years or more have a relative risk of 5.7 of having an unbalanced chromosome abnormality compared with women without elevated risk. Spontaneous abortion rate and prematurity rate did not differ from rates expected without amniocentesis. It is concluded that current indications may be characterized as a mixture of evident high risk factors and factors with only a minor influence on risk. Indications for amniocentesis should therefore be reconsidered. Because it must be considered impractical and ethically wrong to limit amniocentesis to the two mentioned real high risk groups, and illogical to continue to present policy, which is not based on clearcut evidence, the possibility of offering amniocentesis to all who want it, is discussed. Screening for chromosome disease in all pregnancies is not without problems, but may be reasonable in some localities.

High-Risk Pregnancy

To the Editor.— The recent summary on the management of high-risk pregnancy by Pearson (229:1439, 1974) was clear, concise, and almost comprehensive. There is, however, one additional general consideration that practicing obstetricians should keep in mind. Pregnancy is a time of joy for most couples, but also a time of great stress and anxiety. There are reports suggesting that excessive amounts of emotional stress or anxiety may increase the probability of spontaneous abortion and prematurity. 1 In addition, there is a gradually increasing body of information suggesting that stress and anxiety during pregnancy can affect both the neonatal behavior of the infant and the attachment between the parents and the infant. 2,3 Since couples in high-risk pregnancies are likely to be especially anxious, it is important that obstetricians make special provisions to provide these parents with emotional support. Such support can be provided in a variety of ways, including the

Spontaneous premature rupture of the membranes.

Summary: Sixty patients with premature rupture of the membranes occurring between 26 and 37 weeks of gestation who were not in labour 48 hours later were studied prospectively. There were 12 perinatal deaths (20%). The average prolongation of pregnancy with a regime of strict bed rest was 14 days. This regime was considered preferable to one of active intervention, since the perinatal loss from infection was offset by the gain resulting from increased maturity. Progestogen therapy in the doses used was ineffective in postponing the onset of labour. Four perinatal deaths were associated with infection: in one infant a significant infection in the vagina caused a neonatal pneumonia, in another infant the pneumonia was acquired by transplacental infection, whilst in the other 2 infants the portal of entry of the infection was not demonstrated. Serial vaginal bacteriological smears and white cell counts were usually of no assistance in detecting the foetus at risk. Induction of labour in selected instances is not practicable in the absence of some means of detecting the foetus at risk. No such means of detection became apparent in this study.