Abortion Outcomes Research Articles

Racism, Poverty, Abortion, and Other Reproductive Outcomes

The Authors Reply: Rooney encourages epidemiologists to “have the courage to explore controversial risks” when seeking explanations for higher rates of preterm delivery among African-American women. Curiously, his definition of courage seems to entail considering only induced abortion as a possible risk factor. He is notably silent, however, on the courage required to address racism forthrightly as a possible determinant of population distribution of preterm delivery. 1,2 Generating a hypothesis requires at least two obligations. One is development of a plausible causal scenario. The other is a comprehensive and critical review of evidence pro and con. Rooney, however, neither proposes a plausible biological mechanism linking risk of preterm delivery to induced abortion, nor does he acknowledge (a) epidemiologic research finding no evidence of association between induced abortion and subsequent risk of preterm delivery, 3–11 (b) substantive flaws in the studies he cites in favor of his hypothesis (for example, failing to control for parity 12), or (c) research explicitly refuting his hypothesis. 13–16 Specifically, two studies comparing risk of preterm delivery among African-American compared with U.S. white women that take into account history of abortion and other relevant confounders still report a nearly twofold higher risk among the African-American women, 13,15 and two report a 1.4–1.5-fold higher risk 14,16 —and all four investigations are among the studies Rooney cites in favor of his hypothesis! As a corrective, we accordingly note that the preponderance of epidemiologic research indicates either no association or only a very small association between induced abortion and risk of preterm delivery 3–11 (the same is true for risk of breast cancer and abortion, which Rooney also invokes, despite recent studies addressing limitations of earlier investigations, superseding possible biological plausibility of a hypothesized association 17–27). The leading postulated pathway linking induced abortion and subsequent risk of preterm delivery is excessive cervical dilation, which may weaken the cervix, thereby possibly leading to cervical incompetence in a subsequent pregnancy. 3–5 Yet, at present 96.7% of legal abortions in the United States are performed by vacuum aspiration, 28 a procedure not involving excessive dilation of the cervix. Even this retelling of the evidence, however, barely begins to tackle the many other issues on which Rooney is silent. Among the nine studies Rooney cites, 12–16,29–32 six include minimal or no socioeconomic data, 12,13,16,28,29,32 even though socioeconomic position is known to be associated with both likelihood of abortion and risk of preterm delivery, thereby leaving considerable room for residual confounding. 1,33 Similarly, as noted by Collins et al, 2 to date remarkably little research has explored associations between other social phenomena that are distressingly prevalent and potentially linked to risk of preterm delivery: racism, violence, and poverty across the life course and possibly even intergenerationally. 1,2,34 Relevant distinct pathways linking these social phenomena to their embodied biological expression include links between social and material deprivation and infection; neuroendocrine disruption resulting from chronic exposure to discrimination or threats of violence; and restricted access to health care, including family planning services. Courage? It takes courage to look fairly at evidence supporting—let alone contradicting–one’s prior beliefs. Nancy Krieger Janet Rich-Edwards

The roles of clinical assessment, human chorionic gonadotropin assays, and ultrasonography in medical abortion practice

The clinical assessment of patients who request early medical abortion includes confirmation of the diagnosis of pregnancy and estimation of gestational age. Accurate gestational dating is essential, because the efficacies of medical abortion regimens decline as pregnancy advances. Whereas medical abortion researchers in the United States have relied on routine ultrasonography for gestational dating, abortion providers experienced with mifepristone and prostaglandin regimens outside the United States have reported high efficacy and safety primarily with clinical dating parameters. Diligent follow-up of patients allows clinicians to confirm that complete abortion has occurred without complications. In cases of uncertain outcome or suspected ectopic pregnancy, transvaginal ultrasonography and β-human chorionic gonadotropin assays can assist in prompt diagnosis and management. As medical abortion with mifepristone and misoprostol becomes more prevalent in the United States, studies will be needed to further evaluate the effects of these modalities on medical abortion outcomes. (Am J Obstet Gynecol 2000;183:S34-S43.)

Early medical abortion with methotrexate: Outcome and satisfaction among women aged 15–20 years

Background: We investigated the outcomes of women under age 21 who participated in a multi-center case series of early medical abortion using methotrexate and misoprostol.Methods: We enrolled 1973 women in a case series for medical abortion in the first seven weeks of pregnancy, using a standardized protocol and consent for methotrexate (50 mg/m2) and misoprostol (800 mg vaginally, repeated as needed).For this study, women who presented for abortion prior to their 21st birthday were compared to older women. Outcomes of abortion were classified as complete medical abortion (CMA) and suction curettage (SC). Secondary outcomes included symptoms. We did an exit interview assessing patient satisfaction during the first year of the study, and have exit interview data for approximately half of the women enrolled.We assessed the relationship of age and outcomes first by bivariate analysis using SAS (SAS Institute, Inc., Cary, NC). A multiple logistic regression model was constructed using age, gestational age, and measures of parity.Results: There were 219 women who were under 21 (18 under the age of 18). Compared to older women, adolescents presented for abortion at the same gestational ages. Compared to older women, younger women were less likely to have finished college (2.8% vs. 38.7%), and were less likely to have had previous pregnancies (45.4% vs 76.6%) and live births (20.2% vs. 51.3%)The distribution of symptoms during abortion, such as bleeding and cramping, was the same across age groups; the only symptom which was more frequently found in younger women was headache.Overall younger women had a slightly higher rate of CMA as older women (90.2% vs. 86.5%). However, the multiple regression (MR) model did not show an effect of the woman's age on CMA. MR demonstrated an adverse effect of prior live birth, and advancing gestational age on rates of CMA; younger women were less likely to have had prior live births.Younger women were just as likely to report overall satisfaction (86.7% vs. 84.6%) with the abortion procedure and other questions of satisfaction, but were less likely to agree that the bleeding and cramping were acceptable.Conclusions: Younger women having medical abortion with methotrexate and misoprostol have similar outcomes and satisfaction levels as do older women. There is no reason to discourage adolescents who seek abortion from using a medical technique.

Incidence of spontaneous abortion in Bahrain before and after the Gulf War of 1991

Objectives: To determine the incidence of spontaneous abortions in the 5 years before and 5 years after the Gulf War of 1991 and to explore the possible causes that may have affected these changes. To analyze the clinical types, associated medical problems, morbidity, length of hospital stay and mortality rate of abortions. Design: Retrospective study for the period starting on 1 January 1987–31 December 1996. Subjects: The study involved 14 850 cases of abortions admitted into Salmaniya Medical complex during this period. Setting: The Salmaniya Medical Complex (SMC) is the main referral hospital in Bahrain. Methods: Analysis of medical records of patients admitted with diagnosis of abortion during this period. Results: By comparing the incidence of abortions in the 5 years before (1 January 1987–31 December 1991) and the 5 years after (1 January 1992–31 December 1996) the Gulf War a significant rise was observed — starting from 1992, reaching a peak in 1994, which then began to decline in 1996. Conclusion: Several published reports from Iraq, Kuwait and now from Bahrain are suggestive of an increase in the incidence of abortion and adverse outcome of pregnancy after the Gulf War of 1991. The mechanism is not clear, i.e. whether this is affected by toxicity acquired through the food chain, the oil spillage, smoke pollution resulting from the burning of the Kuwaiti oil fields or stress and anxiety caused by the war.

The efficacy of medical abortion: a meta-analysis

Multiple clinical studies demonstrate the efficacy of medical abortion with mifepristone or methotrexate followed by a prostaglandin analogue. However, assessing predictors of success, including regimen, is difficult because of regimen variability and a lack of direct comparisons. This meta-analysis estimates rates of primary clinical outcomes of medical abortion (successful abortion, incomplete abortion, and viable pregnancy) and compares them by regimen and gestational age. We identified 54 studies published from 1991 to 1998 using mifepristone with misoprostol (18), mifepristone with other prostaglandin analogues (23), and methotrexate with misoprostol (13). Data abstracted from studies included regimen details and clinical outcomes by gestational age. We found that efficacy decreases with increasing gestational age (p <0.001), and differences by regimen are not statistically significant except at gestational age ≥57 days. For gestations ≤49 days, mean rates of complete abortion were 94–96%, incomplete abortion 2–4%, and ongoing (viable) pregnancy 1–3%. For gestations of 50–56 days, the mean rate of complete abortion was 91% (same for all regimens), incomplete abortion 5–8%, and ongoing pregnancy 3–5%. For ≥57 days, success was lower for mifepristone/misoprostol (85%, 95% confidence interval 78–91%) than for mifepristone/other prostaglandin analogues 95% (CI 91–98%, p = 0.006). For mifepristone/misoprostol, using ≥2 prostaglandin analogue doses seems to be better than a single dose for certain outcomes and gestational ages. We conclude that both mifepristone and methotrexate, when administered with misoprostol, have high levels of success at ≤49 days gestation but may have lower efficacy at longer gestation.

Threatened abortion outcome in relation to intrauterine clot site and not only volume

Threatened abortion outcome in relation to intrauterine clot site and not only volume

Outcomes of suction curettage and mifepristone abortion in the United States: A prospective comparison study

A prospective, nonconcurrent cohort analysis of 178 mifepristone/misoprostol and 199 suction curettage abortion subjects, ages ≥ 18 years, with intrauterine pregnancies ≤ 63 days estimated gestational age, was conducted to compare the outcomes of suction curettage abortion to those of medical abortion. The medical abortion subjects received 600 mg of mifeprisone orally, followed by 400 μg of oral misoprostol 2 days later. Surgical abortion subjects underwent electronic vacuum aspiration. All subjects were followed for 2 weeks or until the absence of clinical bleeding. Outcome measures included a successful abortion (complete abortion without a surgical intervention), duration of bleeding, and morbidity. Overall, 18.3% medical and 4.7% surgical patients failed their primary procedure and received an unanticipated suction curettage (RR 3.93;95% CI 1.87, 8.29). Four mifepristone subjects required curettage for acute bleeding, nine to manage ongoing pregnancy, and five for incomplete abortion. Fourteen mifepristone and eight surgical subjects required curettage for persistent bleeding. The median time delay for therapeutic curettage was significantly longer in the medical abortion group (35 versus 8 days; Mann-Whitney U = 17.0, p = 0.008). Medical subjects experienced significantly longer bleeding (mean difference = 9.6 days, 95% CI 6.8, 12.4). No significant change in hemoglobin occurred in either group. Mifepristone patients reported significantly greater pain (77.1% vs 10.5%; RR 7.4, 95% CI 4.7, 11.5), and nausea or vomiting (68.6% vs 0.6%; RR 117.9, 95% CI 16.7, 834.7). Women receiving mifepristone/misoprostol are more likely to require an unplanned surgical intervention than women who undergo suction curettage. They experience more discomfort with their procedure and in the follow-up interval, bleed for a longer period, and remain at risk for surgical completion curettage for several weeks

Success rates and estimation of gestational age for medical abortion vary with transvaginal ultrasonographic criteria

Objective: Our purpose was to evaluate differences in gestational age and success rates for medical abortion patients obtained by using several nomograms for mean sac diameter and embryonic pole. Study Design: A retrospective review of 1011 patients was performed; the data were from 8 published studies and private patients of the primary author (M.D.C.) who received methotrexate and misoprostol for abortion. The ultrasonographic findings at baseline examination were used to estimate gestational age according to criteria established by Hellman et al and Rossavik et al for mean sac diameter and Robinson, Hadlock et al, and Goldstein and Wolfson for the embryonic pole. The assigned gestational ages of the study population were then compared, and the success rates of treatment at various gestational ages were calculated for each of the dating criteria. Results: Outcomes on the basis of gestational age for those patients who had only a gestational sac were similar regardless of which gestational age criteria were used. The final assessment of gestational age by embryonic pole according to the criteria of Goldstein and Wolfson was significantly different from the others. Conclusions: Medical abortion outcomes will vary depending on which criteria are used for establishing gestational age by both mean sac diameter and embryonic pole. (Am J Obstet Gynecol 1999;180:35-41.)

Risk of preterm delivery, low birthweight and growth retardation following spontaneous abortion: a registry-based study in Denmark.

Some studies have found an association between spontaneous abortion and adverse birth outcome in the subsequent pregnancy, but results are conflicting, maybe due to lack of confounder control. Using population-based registries we identified a cohort of 45 449 women having a livebirth preceded by a spontaneous abortion ('abortion cohort'), and a random sample of 9752 women with two consecutive livebirths ('reference cohort'). We examined the risk of preterm (<37 weeks gestation) and very preterm delivery (<34 weeks), low birthweight and growth retardation in both births in the reference cohort compared with births following an abortion, controlling for social factors and interpregnancy interval. Compared to second births in the reference cohort, the abortion cohort had higher risks for preterm (odds ratio [OR] = 1.74, 95% CI: 1.5-2.0) and very preterm delivery (OR = 2.17, 95% CI : 1.7-2.7), low birthweight (OR = 1.76, 95% CI: 1.5-2.1), and growth retardation (OR = 1.50, 95% CI: 1.4-1.6). In the reference cohort 3.9% of the pregnancies ended as preterm deliveries, 1 % as very preterm, 3.3% as low birthweight, and 8.1% as growth retarded. Women with two or more previous abortions had a higher risk for preterm and very preterm delivery. When first liveborns of women in the reference cohort were compared with first liveborns in the abortion cohort, only deliveries before 34 and 37 weeks' gestation were associated with previous abortion. Spontaneous abortion is associated with preterm delivery (both <34 and <37 weeks) in the subsequent pregnancy. Women who become pregnant following an abortion should receive special attention in the antenatal clinics.

Chlamydial lower genital tract infection and spontaneous abortion

Objective Few previous studies have examined the role that acute Chlamydia trachomatis lower genital tract infection plays in the development of spontaneous abortion. This study evaluated cervical C. trachomatis infections among 52 women experiencing spontaneous abortion and 59 controls. Methods Pregnant women at less than 22 weeks of gestation who sought medical care in an emergency department in West Philadelphia were eligible for enrollment. Urine samples from enrolled women were tested for chlamydia using ligase chain reaction DNA amplification. All women were followed up to 22 weeks of pregnancy to ascertain the outcome of spontaneous abortion. Results The proportion of women with chlamydial infection was 3.8% among spontaneous abortion cases and 8.5% among controls. After adjustment for potentially confounding factors, there was no substantial difference in the rate of chlamydial infection between women with and without spontaneous abortion (odds ratio 1.8, 95% confidence interval 0.3–10.7). Conclusion These data do not support a relationship between acute C. trachomatis infection and the development of spontaneous abortion. Infect. Dis. Obstet. Gynecol. 6:8–12, 1998. © 1998 Wiley-Liss, Inc.

Chlamydial Lower Genital Tract Infection and Spontaneous Abortion

Objective:Few previous studies have examined the role that acuteChlamydia trachomatislower genital tract infection plays in the development of spontaneous abortion. This study evaluated cervicalC. trachomatisinfections among 52 women experiencing spontaneous abortion and 59 controls.Methods:Pregnant women at less than 22 weeks of gestation who sought medical care in an emergency department in West Philadelphia were eligible for enrollment. Urine samples from enrolled women were tested for chlamydia using ligase chain reaction DNA amplification. All women were followed up to 22 weeks of pregnancy to ascertain the outcome of spontaneous abortion.Results:The proportion of women with chlamydial infection was 3.8% among spontaneous abortion cases and 8.5% among controls. After adjustment for potentially confounding factors, there was no substantial difference in the rate of chlamydial infection between women with and without spontaneous abortion (odds ratio 1.8, 95% confidence interval 0.3–10.7).Conclusion:These data do not support a relationship between acuteC. trachomatisinfection and the development of spontaneous abortion.

Traditions and reproductive technology in an urbanizing north Indian village

This article addresses the practices of prenatal sex determination and sex-selective abortion through ethnographic research in Shahargaon, a Jat village undergoing rapid urbanization and cultural change in north India. The paper presents the sociodemographic outcomes of sex-selective abortion practiced within a system of patriarchy, manifested in terms of son preference and daughter disfavor. It argues that changes from an agriculture to an urban economy have led to a decrease in family size among Shahargaon Jats. In spite of improvements in educational and economic status, there is a reinforcement of son preference and daughter disfavor in the Jat community in Shahargaon. Jat couples are using prenatal sex determination and sex-selective abortion to achieve smaller family size and to reduce the number of daughters in a family.

Urine beta-core fragment, a potential screening test for ectopic pregnancy and spontaneous abortion.

The incidence of ectopic pregnancy in the United States has risen 6-fold in the last three decades. It now accounts for about 2% of reported pregnancies. Tests are now needed to identify ectopic pregnancy before it is clinically evident. We evaluated human chorionic gonadotropin beta-core fragment as a test to predict ectopic pregnancy and spontaneous abortion. Urine samples were collected from women with in vitro fertilized pregnancies, 2 1/2-5 weeks after embryo transfer. Fifty samples were collected from those later shown to have normal intrauterine pregnancies, samples from 13 women subsequently found (at 5-9.3 weeks) to have ectopic gestations, and 15 from those with impending spontaneous abortion. Beta-Core fragment levels were determined by immunoassay, and results normalized to creatinine concentration. Median beta-core fragment levels at 2 1/2-3, 3-4, and 4-5 weeks after embryo transfer, were 6.7, 91 and 737 microg/g for unaffected pregnancies, 1.0, 5.9 and 0.6 microg/g for impending ectopic pregnancies (0.15, 0.065 and 0.0008, multiples of the unaffected pregnancy median, MoM), and 0.75, 6.8 and 12 microg/g for impending spontaneous abortions (0.11, 0.07 and 0.016 MoM). A gestation-linked curve was modeled to discriminate unaffected pregnancy from impending ectopic gestation or spontaneous abortion. Plotted beta-core fragment levels were below this curve in 12 of 13 (92%) women with impending ectopic pregnancy, in 10 of 15 (67%) with spontaneous abortion outcome, and in 2 of 50 (4%) with intrauterine pregnancy and term outcome. Measurement of urine beta-core fragment at 2 1/2-5 weeks after embryo transfer (4 1/2-7 weeks after last menstrual period) might be useful for identifying failing pregnancies. Over three quarters (predictive value positive 76%) of those with low beta-core fragment levels have ectopic pregnancy or spontaneous abortion. On the contrary, 95% (predictive value negative) of those with normal range test values may be predicted to have a nonfailing term pregnancy. Diagnosis of ectopic pregnancy could be confirmed by transvaginal ultrasound, and ectopic pregnancy terminated early by nonsurgical methods, with minimal mortality or fertility loss. Major fetal defects that cause spontaneous abort pregnancies may also be recognized by transvaginal ultrasound. In such cases, chorionic villous sampling or possibly termination may be considered.

Early Predictors of Nonmarital First Pregnancy and Abortion

Most research on abortion has focused on women's characteristics at the time of the procedure, but individuals' behavior may also be shaped by their experiences from younger ages. This study uses longitudinal data on 351 California white women aged 27-30 in 1990-1991 to identify characteristics in childhood and adolescence that predict who will have a nonmarital first pregnancy and, of those who do, which women will seek an abortion. Bivariate analyses reveal that psychosocial characteristics indicating a strong sense of autonomy, such as feeling it is important not to be tied down and engaging in socially undesirable behavior, are significantly associated with the likelihood of having a nonmarital first pregnancy (odds ratios of 1.7 and 1.5, respectively), but family characteristics are not. However, among women who have a first pregnancy out of wedlock, the odds of having an abortion are mostly influenced by family rather than psychological characteristics, particularly having been a good student and having a well-educated mother (2.0 and 1.7).

Endometriosis: a stage by stage analysis—the role of in vitro fertilization

To investigate the impact of endometriosis stage on IVF. A retrospective study of 214 patients diagnosed with endometriosis who underwent 360 cycles of IVF at The New York Hospital-Cornell Medical Center. Meanwhile, 111 pure mechanical (tubal) infertility patients treated in 160 cycles at the same time were designated as the control group for comparison. Patient's hormone and semen profiles, hormonal response and outcome to stimulation, as well as the outcome of pregnancy, abortion, and delivery rate were analyzed. No differences in the pregnancy outcome between the endometriosis and control groups were noted when compared among the subgroups of pure endometriosis, endometriosis plus tubal factor, endometriosis plus others (primarily endometriosis plus male factor), and control. Comparing the outcomes in pure endometriosis cases by staging, we could not find any discrepancies in terms of pregnancy rates (PRs) according to the severity of the disease. The addition of GnRH analogur down-regulation to gonadotropin stimulation resulted in an increase in PR. A relatively high delivery rate (38.9% per cycle, 41.9% per retrieval, and 43.2% per transfer) was achieved when the pure endometriosis patients were treated with concomitant leuprolide acetate down-regulation and gonadotropin. We have observed that pregnancy outcome in patients with endometriosis was not different than the outcome for patients with mechanical (tubal) infertility. There were no differences in PRs by stage of endometriosis.

Early Childbearing: Perspectives of Black Adolescents on Pregnancy, Abortion, and Contraception.

Studying the Problem of Teenage Pregnancy Risking Pregnancy Avoidance, Ignorance, and Delay of Contraceptive Use Wanting Pregnancy Teenager's Attitudes, Goals, and Perceived Support Choosing Abortion or Delivery Influences and Outcomes Avoiding Childbearing Teenagers Who Terminated a First Pregnancy Compared to Never-Pregnant Peers Pregnancies After Study Enrollment 'Pregnant Because They are Different or Different Because They are Pregnant?' Family Involvement in Preventing Early Teenage Childbearing Male Teenagers and Contraception Conclusions and Recommendations

Assessment of the fetomaternal circulation in threatened abortion by transvaginal color Doppler.

Transvaginal color Doppler was used to investigate blood flow in the fetomaternal circulation of 60 women with threatened abortion and 90 women with normal intrauterine pregnancy. The obtained Doppler sonograms were analyzed and the resistance index (RI) was calculated in the maternal circulation, while in the fetal circulation the pulsatility index (PI) was used. There was no significant difference in the RI values of the maternal circulation between women with normal pregnancies and pregnancies complicated by bleeding, but with normal pregnancy outcome (p > 0.05). No differences in RI values of the uterine, arcuate and radial arteries were found between pregnancies with threatened abortion and normal pregnancy outcome and women with abnormal outcome (p > 0.05). In 9 of 21 women with visible retrochorionic hematoma, the RI of the spiral arteries was higher on the hematoma side in comparison to the opposite side (p < 0.01). This could be a consequence of the mechanical compression caused by the hematoma. In 3 of 4 cases of missed abortion, the RI of the spiral arteries was lower in comparison to the control group. Such findings could be caused by the vasodilatating products of inflammation which probably exist in such areas. There was no significant difference in terms of the PI of fetal blood vessels between normal pregnancy and threatened abortions with normal outcome, as well as between threatened abortions with normal outcome and subsequent abortions of live fetuses (p > 0.05).

Epidemiological studies in monitoring reproductive effects.

The possible hazards of occupational exposure on the reproductive health of workers is of great interest. In this review, epidemiological study designs suitable for reproductive studies and sources of outcome and exposure data are described with a few examples. Studies have been conducted on hormonal changes, semen quality, fertility, and various outcomes of pregnancy, e.g., spontaneous abortion, congenital malformations, perinatal mortality, birth weight, and health and development of the children. Also, sex distribution of children has been investigated as a possible risk indicator in some recent studies. In epidemiological studies, retrospective or prospective cohort design, case referent and nested case referent designs have been used. The validity of epidemiological studies depend on reliable data on the health effect and the exposure. The registers on congenital malformations and on births and other outcomes of pregnancy are useful sources of data for epidemiological studies. The coverage of the register and the accuracy of its contents should be known if the register is used for research. Personal interview of the worker is an important source of information, although recall problems may weaken the quality of the data. The reliability of the answers may be increased by using a few complementary questions on possible medical confirmation of the event. If both the interview and register data are available, the reliability of the information increases, the same concerns exposure information also. Examples of some conducted studies are given.

Abortion and Pregnant Adolescents

Statistics indicate that the incidence of pregnancy termination through abortion is on the rise among adolescents. This trend is particularly disturbing because many teenagers opting for an abortion disclose that they engaged in unprotected sexual activities. Despite the ostensible willingness of teenagers to rely upon abortion as a method of birth control, evidence suggests that the procedure may have enduring negative repercussions. Previewing, which focuses the adolescent on predicting the likely consequences of her behavior, may be a beneficial therapeutic intervention in these cases. During short-term psychotherapy, previewing may help teenagers anticipate the likely outcome of abortion and thus modify behavior patterns so that pregnancy and abortion may be avoided.

Recent advances in the Doppler study of early fetomaternal circulation.

Transvaginal color Doppler has enabled precise investigation of feto-maternal circulation in early pregnancy. Decrease of peripheral impedance, as well as increase of blood flow velocity was found in all segments of the uteroplacental circulation with gestational age. The same finding was observed in umbilical artery, fetal aorta and intracranial blood vessels. A significant decrease of vascular impedance in cerebral blood vessels exists earlier than in fetal aorta or umbilical artery which could be explained by the establishment of cerebral autoregulation mechanisms which ensure adequate oxygen and glucose supply to embryonic brain. There was no significant difference for RI values of luteal blood flow from the 6th to the 12th gestational week. No difference was found between RI values of luteal blood flow in normal and ectopic pregnancy. In threatened, incomplete and missed abortions RI of luteal blood flow was significantly higher in comparison with normal pregnancy. It seems that in the group of patients with threatened abortion, follow up of the luteal flow might give some prognostic value. No difference in peripheral impedance and blood flow velocity of the uteroplacental blood vessels was found between women with normal pregnancies and women with threatened abortions and normal pregnancy outcome. There was no significant difference in terms of RI and PSV in uteroplacental blood vessels between women with threatened abortion and normal pregnancy outcome and women with threatened abortion whose pregnancy terminated with complete abortion and blighted ovum. In 46% of 21 women with visible retrochorionic hematoma RI in spiral arteries was higher and PSV was lower on the side of the hematoma. These values could be explained by compression of the wall of the spiral arteries caused by hematoma. In missed abortion the mean RI value of the uterine artery was lower than the mean value in normal pregnancy, but was not in spiral arteries. Some authors reported RI values in cases of missed abortions around and above the cutoff point value of 0.63. In blighted ovum RI in uterine and spiral arteries was lower in comparison to normal pregnancy, but in the other studies this was not the case. Increased blood flow in radial arteries in patients with pregnancy associated with uterine myomata could be explained by higher levels of estriol hormone metabolized in the placenta. Transvaginal color Doppler could be helpful in diagnosis and differentiation of the different forms of a gestational trophoblastic disease. It seems that this technique is a good substitute for pelvic angiography.(ABSTRACT TRUNCATED AT 400 WORDS)