Obstetric Implications Research Articles

The Implications of a False Positive Second-Trimester Serum Screen for Down Syndrome

In Brief OBJECTIVE To investigate the genetic and obstetric implications of false positive Down syndrome serum screening results. METHODS The study population comprised 162,774 women underwent triple marker screening in the Ontario Maternal Serum Screening program between October 1995 and September 1998, with outcomes obtained from the Canadian Institute of Health Information. The study compares the incidence of chromosomal abnormalities other than Down syndrome in screen positive women with background incidence from the literature. It also compares the risks of having a fetus with congenital abnormalities or of developing obstetric complications in 11,549 screen positive women with their matched controls. RESULTS A higher incidence of trisomy 13 (12.4 per 10,000) was seen in screen positive women; the incidence of other chromosomal abnormalities in screen positive women was not increased relative to the general population. The higher incidence of trisomy 13 may have been biased by the selective uptake of amniocentesis in women who had high risks for Down syndrome or abnormal ultrasound findings. Incidences of fetal congenital abnormality in screen positive and negative women were similar. Women who screened positive for Down syndrome had increased risk of spontaneous fetal loss (odds ratio 1.80; 95% confidence interval 1.54, 2.07) but no other obstetric complications. CONCLUSION Among women who screened positive for Down syndrome, we found a higher number of spontaneous fetal losses and a possibly higher risk of having a fetus with trisomy 13. We did not find an increased risk for other chromosomal abnormalities, congenital abnormalities, or other adverse obstetric outcomes. Screening positive for Down syndrome indicated a possible higherrisk for trisomy 13 and a higher risk for spontaneous fetal loss but not other adverse outcomes.

The Webster Technique: A chiropractic technique with obstetric implications

Objective: To survey members of the International Chiropractic Pediatric Association (ICPA); regarding the use of the Webster Technique for managing the musculoskeletal causes of intrauterine constraint, which may necessitate cesarean section. Methods: Surveys were mailed to 1047 US and Canadian members of the ICPA. Results: One hundred eighty-seven surveys were returned from 1047 ICPA members, constituting a return rate of 17.86%. Seventy-five responses did not meet the study inclusion criteria and were excluded; 112 surveys (11%) provided the data. Of these 112 surveys, 102 (92%) resulted in resolution of the breech presentation, while 10 (9%) remained unresolved. Conclusion: The surveyed doctors reported a high rate of success (82%) in relieving the musculoskeletal causes of intrauterine constraint using the Webster Technique. Although the sample size was small, the results suggest that it may be beneficial to perform the Webster Technique in month 8 of pregnancy, when breech presentation is unlikely to spontaneously convert to cephalic presentation and when external cephalic version is not an effective technique. When successful, the Webster Technique avoids the costs and/or risks of external cephalic version, cesarean section, or vaginal trial of breech.In view of these findings, the Webster Technique deserves serious consideration in the health care management of expectant mothers exhibiting adverse fetal presentation. (J Manipulative Physiol Ther 2002;25:000)

Primary infertility associated with isolated cervical collecting diverticulum

Objective: To describe a previously unreported isolated congenital cervical diverticulum and its gynecologic, reproductive, and obstetrical implications. Design: Case report. Setting: A university hospital. Patient: A 31-year-old woman presenting with menometrorrhagia and primary infertility. Investigation revealed an isolated collecting cervical diverticulum causing prolonged postmenstrual spotting, possibly interfering with sperm capacitation and access to the uterine cavity. Intervention(s): The examination included hysterosalpingography and magnetic resonance imaging. The combined hysteroscopy and laparoscopy revealed a 5 × 5 cm cervical diverticulum, around 1 cm from the external cervical os, leading to a short cervical canal connected to a normal uterine cavity. The patient achieved a pregnancy after controlled ovarian hyperstimulation and ultrasonographically guided intrauterine insemination. Main Outcome Measure(s): Pregnancy and obstetrical outcome. Result(s): Extensive evaluation revealed the patient’s condition to be a previously undescribed congenital cervical anomaly. The patient’s infertility was corrected by ovulation induction and sonographically guided intrauterine insemination, which resulted in a twin pregnancy. After 27 weeks of gestation, preterm labor complicated the delivery. Conclusion(s): The diagnosis and management of this unusual congenital cervical diverticulum present a particular challenge, as this congenital abnormality has not been previously described or reported.

Pregnancy and Infection With Human Immunodeficiency Virus

During the past decade, there has been a dramatic increase in the number of women infected with HIV and the number of women with clinical AIDS. One of the most prominent features of HIV infection is that it is usually diagnosed during the peak reproductive years, and in 1998, HIV/AIDS was the fourth leading cause of death among women between the ages of 25 and 44 years. For this reason, there has been long-standing concern regarding the obstetric implications of HIV infection: both the impact of pregnancy on possibly accelerating the course of HIV disease and the impact of HIV infection on the course of pregnancy. There appears to be some immunologic changes associated with pregnancy, but they are not dramatic, and immune markers generally resume their prepregnancy values after delivery. With regard to long-term effects of pregnancy on HIV disease progression, no study to date has shown significant increases in mortality or in AIDS incidence associated with pregnancy. Studies have generally been small, however, and none have accounted for antiretroviral therapy usage. Many studies have shown that certain adverse outcomes are more common in HIV-positive pregnant women as compared with HIV-negative pregnant women, and concerns have been raised that spontaneous abortions may be more common among HIV-infected women and that this may impact fertility rates. Although important understanding has been acquired regarding the associations between pregnancy and the course of HIV infection, much remains to be understood. Additional, well-designed studies are clearly needed to rigorously address the many remaining questions that exist. We can anticipate that the resolution of these questions will continue to be of broad public health interest as the epidemic impacts increasing numbers of women, a large fraction of whom will be adolescents.

Obstetric Implications of Antiphospholipid Antibodies: Pregnancy Loss and Other Complications

Obstetric Implications of Antiphospholipid Antibodies: Pregnancy Loss and Other Complications

Management of stage I cervical cancer in pregnancy.

Although cervical carcinoma is the most common gynecologic malignancy associated with pregnancy, its occurrence is rare with an incidence of approximately 1 per 1,200 to 10,000 pregnancies. There are inadequate data addressing both the obstetric implications of the diagnostic evaluation and the impact of intervention on maternal and infant outcomes. Certain conclusions and recommendations, however, can be drawn from the available data. Diagnostic evaluation includes cytological screening, colposcopy and if necessary, biopsy, and selective conization. Staging of the pregnant patient is modified to minimize radiation exposure to the developing fetus. The treatment schema for patients with stage I cervical cancer in pregnancy varies with the stage of disease and gestational age at diagnosis. With close surveillance, deliberate delay of therapy to achieve fetal maturity is a reasonable option for patients with microinvasive and early stage IB cervical cancer. Tumor characteristics and maternal survival are not adversely affected by pregnancy. Conversely, cervical cancer does not seem adversely to affect pregnancy. However, timing and type of therapy may have a significant influence on the fate of the fetus. In counseling patients with cervical cancer during pregnancy, many factors must be considered, including the patient's desire for the pregnancy, stage of disease, and gestational age at diagnosis. Pregnant patients with stage I cervical cancer should be fully informed of all possible treatment options and consequences. The care of these patients should be closely coordinated by experts in perinatology and gynecologic oncology. Obstetricians & Gynecologists, Family Physicians After completion of this article, the reader will be able to describe the signs and symptoms of cervical cancer during pregnancy and the indications for conization during pregnancy, as well as being able to outline management strategies for the various stages of cervical cancer during pregnancy.

Insulin-like growth factor binding protein-1 (IGFBP-1): a multifunctional role in the human female reproductive tract.

Insulin-like growth factor-1 (IGFBP-1) is particularly important in human female reproductive physiology, where it is involved with other factors in a complex system which regulates menstrual cycles, puberty, ovulation, decidualization, implantation and fetal growth. This has implications for clinical obstetrics and gynaecology, where there is evidence for a pathophysiological role for IGFBP-1 in pre-eclampsia, intrauterine growth restriction, polycystic ovarian syndrome and trophoblast and endometrial neoplasms.

The clinical application of interphase FISH in prenatal diagnosis

Fluorescence in situ hybridization (FISH) for five chromosomes (13, 18, 21, X and Y) detected 87 of 107 (81%) of the chromosome aberrations identified by conventional chromosome analysis applied to fetal interphase cells obtained by chorionic villus sampling or amniocentesis. The choice of FISH was solely determined by prospective parents after formal genetic counselling concerning the advantages and disadvantages of FISH analysis. Excluding known familial chromosome aberrations, if FISH analysis revealed normal signals, there was an overall residual risk of 1 in 149 for an undetectable chromosome aberration. This risk varied according to the indication for prenatal diagnosis: 1 in 177 for women of advanced maternal age; 1 in 60 for women at increased risk for Down syndrome based on maternal serum screening; and, 1 in 43 for women whose ultrasound examination revealed fetal anomalies. There were 20 cases of discordance between the FISH results and standard karyotype analysis: four were the outcome of a failure to apply the appropriate FISH probe; 16 were not detectable by the available FISH probes. Of these 16, nine were chromosome abnormalities with clinical significance and seven were familial. If FISH is to become a standard part of prenatal genetic diagnosis, genetic counselling that is sensitive to patient health needs must be based on accurate information about the biological and obstetrical implications of the results of FISH analysis.

The clinical application of interphase FISH in prenatal diagnosis

Fluorescence in situ hybridization (FISH) for five chromosomes (13, 18, 21, X and Y) detected 87 of 107 (81%) of the chromosome aberrations identified by conventional chromosome analysis applied to fetal interphase cells obtained by chorionic villus sampling or amniocentesis. The choice of FISH was solely determined by prospective parents after formal genetic counselling concerning the advantages and disadvantages of FISH analysis. Excluding known familial chromosome aberrations, if FISH analysis revealed normal signals, there was an overall residual risk of 1 in 149 for an undetectable chromosome aberration. This risk varied according to the indication for prenatal diagnosis: 1 in 177 for women of advanced maternal age; 1 in 60 for women at increased risk for Down syndrome based on maternal serum screening; and, 1 in 43 for women whose ultrasound examination revealed fetal anomalies. There were 20 cases of discordance between the FISH results and standard karyotype analysis: four were the outcome of a failure to apply the appropriate FISH probe; 16 were not detectable by the available FISH probes. Of these 16, nine were chromosome abnormalities with clinical significance and seven were familial. If FISH is to become a standard part of prenatal genetic diagnosis, genetic counselling that is sensitive to patient health needs must be based on accurate information about the biological and obstetrical implications of the results of FISH analysis. Copyright © 2000 John Wiley & Sons, Ltd.

Obstetric Implications of Activated Protein C Resistance and Factor V Leiden Mutation

An increasing number of reports have focused on activated protein C resistance (APCR) as it has been shown not only to be the most common genetic factor predisposing patients to thromboembolic disease but the most common identifiable cause overall. More than 90 percent of the cases of APCR are caused by the factor V Leiden mutation, in which a guanine to adenine substitution in the factor V gene at nucleotide position 1691 results in a glutamine to arginine switch at position 506. Recent studies have also pointed to evidence of an association between APCR/factor V Leiden mutation and hypertensive disorders of pregnancy, first and second trimester miscarriage, placental infarction, and placental abruption.

Superfecundation and Dual Paternity in a Twin Pregnancy Ending with Placental Abruption

A case of superfecundation and dual paternity in a twin pregnancy is presented. Placental abruption developed at week 33 of gestation and the two boys had to be saved by emergency cesarean section. As they shared one placenta, had almost identical weight and had the same sex, they were assumed to be monozygotic. However, a subsequent paternity suit led to the conclusion, based on DNA-analysis, that the twin brothers had been fathered by two different men. Obstetrical implications are discussed.

Serum inhibin A levels in pregnant women with systemic lupus erythematosus or antiphospholipid syndrome

Maternal serum inhibin A levels are increased on average in pregnancies affected by Down syndrome (DS). However, some reports have found increased serum levels in women with pre-eclamptic toxaemia as well. In the current study, maternal serum inhibin A was retrospectively measured in a series of 32 serum samples from pregnant women previously diagnosed as having either systemic lupus erythematosus (SLE) or primary antiphospholipid syndrome (APS). For comparison, normal medians were calculated from 57 unaffected control pregnancies together with a total of 854 samples tested at 13-19 weeks of gestation as part of the routine antenatal DS screening. All results were expressed in multiples of the gestation specific normal medians (MoM). A cubic regression formula was fitted, weighting for the number of women tested at each gestation. The median MoM value in the 16 cases of SLE and the 16 cases of primary APS is 0.60 (95% confidence interval 0.40-0.91) and 0.88 (95% confidence interval 0.66-1.17), respectively. For primary APS this was not statistically significant, whereas the SLE patients had a highly statistically significant reduction of serum inhibin A (p<0.002, Wilcoxon Rank sum Test, 2 tailed). Six pregnancies in the SLE group had a complicated obstetric outcome, i.e. missed abortion, placental abruption, exacerbation of the underlying disease which necessitated delivery, and severe postpartum haemorrhage. In 85% of this subgroup, serum inhibin A levels were below the normal 10th centile. The current data suggest that serum inhibin A is decreased on average in SLE patients. Those preliminary results might have various obstetric implications such as antenatal DS screening of SLE patients, identification of pregnant women at risk of developing SLE, who have presented for routine DS screening and for monitoring SLE patients throughout their pregnancy.

The diagnosis and obstetrical implications of bacterial vaginosis

Bacterial vaginosis (BV) is an important polymicrobial state of abnormal genital tract colonisation which is easy to diagnose and easy to treat but which is poorly understood and therefore ignored or neglected by clinicians. Despite this, or perhaps as a result, BV is increasingly being associated with adverse sequelae in the practice of both obstetrics and gynaecology.

The obstetric implications of teenage pregnancy.

A retrospective review was performed on the obstetric outcome of teenage pregnancies delivered in 1 year in a tertiary centre. The results were compared with the rest of the obstetric population in the same hospital in the same year. The teenage mothers (n = 194) had increased incidence of sexually transmitted diseases (5.2 versus 1.0%, P < 0.05), and preterm labour (13.0 versus 7.0%, P < 0.01), but decreased incidence of gestational glucose intolerance (3.1 versus 11.4%, P < 0.001), when compared with the non-teenage mothers (n = 4914). There was no difference in the types of labour, while the incidence of Caesarean section was lower (4.1 versus 12.6%, P < 0.001) in the teenage mothers. Although the incidence of low birthweight was higher in the teenage mothers (13.5 versus 6.5%, P < 0.001), there was no significant difference in the mean birthweight, gestation at delivery, incidence of total preterm delivery, or perinatal mortality or morbidity. The results indicate that the major risk associated with teenage pregnancies is preterm labour, but the perinatal outcome is favourable. The good results accomplished in our centre could be attributed to the free and readily available prenatal care and the quality of support from the family or welfare agencies that are involved with the care of teenage mothers.

Obesity and its obstetric implications

Obesity has long been regarded as an obstetric hazard. This study identified 300 primipara patients aged 20-29 years who were classified according to the estimated pre-pregnancy Body Mass Index (BMI). The study population was sub-divided into the lean (BMI < 25 kg/m2, n = 189), the overweight group (BMI 25-29, n = 73), and the obese group (BMI > 30, n = 38). The obese group had a statistically higher incidence of hypertensive disease when compared to the lean group. They also had a statistically higher incidence of oedema, glycosuria, vaginal infections and impaired glucose tolerance. There was no statistical difference in the incidence of a past history of a fetal loss, and a history of vaginal bleeding in the first two trimesters. Antenatal follow-up of the pregnancy in the obese group was more difficult requiring more frequent ultrasonic investigations. The obese group had a tendency towards a prolonged labour, but there did not appear to be any difference in the mode of delivery. Infants of obese women had significantly lower 1 min APGAR scores. These infants were significantly larger than those born to lean women. There was no increase in the incidences of post-partum problems.

Obstetric and neonatal implications of HIV infection

Obstetric and neonatal implications of HIV infection

Obstetric implications of neanderthal robusticity and bone density

Neanderthal pelvic morphology is not well understood, despite the recent find and analysis of the Kebara 2 pelvis. Many of the proposed hypotheses focus on the possible need for a larger birth canal. A previously unexplored aspect involves possible direct obstetric implications of bone robusticity and density. These characteristics ocan affect obstetrics in modern humans, especially the molding of the neonate's head during parturition: engineering studies have shown that denser neonate cranial bones undergo less deformation, and thicker (more robust) cranial bones would also be expected to deform less during the birth process. These bone characteristics may also result in a less flexible birth canal. Thus, more robust or denser bones could result in the need for a larger birth canal or a smaller neonate head, due to decreased flexibility. Examples from modern populations are discussed and the conclusions applied to Neanderthals, who are known to have had high bone robusticity and may have had high bone density, given their heavy musculature. (A positive association between muscle mass and bone density has been observed repeatedly in modern humans.) We conclude that bone robusticity and density may have obstetrical implications for Neanderthals, with particular importance for neonate head molding during birth.

Obstetrical implications in multiple pregnancies.

In the present study 90 multiple pregnancies were examined. These were subdivided on the basis of the number of embryos involved (74 twins, 10 triplets, 6 quintuplets) and on whether they were followed at our clinic for the entire pregnancy or not. In each group we analysed certain variables, calculating the respective mean values and standard deviations. We used the ANOVA test to discriminate the eventual differences in the means of the variables analysed, operating a p < 0.05 significance value. In addition, significant differences were analysed by the test of Contrasts (Scheffe F-test). The concept that emerged from the data investigated is that careful management of these pregnancies, carried out in high-level structures, can reduce the incidence of complications on both the maternal and fetal side and thus prevent "minimal brain damage" in the newborn.

MATERNAL SERUM SCREENING FOR ANEUPLOIDY AND OPEN FETAL DEFECTS

The application of population-based maternal serum screening to prenatal diagnosis has been shown to be practical and is now wide-spread. It has been estimated that more than 40% of genetics programs in the United States that offer second trimester maternal serum screening now use at least one analyte in addition to AFP (Dr. George J. Knight, personal communication). The studies described here suggest that additional refinements in maternal serum screening are not only possible but inevitable. The use and interpretation of the analytes AFP, uE3, and hCG continue to be examined and expanded upon (Table 1). In the future, it seems logical that other analytes may be added or may replace one or more of these currently used markers. We have demonstrated that with AFP, uE3, and hCG, a separate protocol will identify a significant portion of trisomy 18 fetuses with a minimal increase in the number of amniocenteses performed. Other significant aneuploidies, including Turner syndrome and triploidy, will be identified in screening for Down syndrome and trisomy 18. Although separate screening protocols for the detection of Turner syndrome and triploidy would not be of practical value, their detection within a screening protocol for Down syndrome is an added benefit and increases the value of the screening markers. The use of first trimester screening is being investigated. Although earlier diagnosis is attractive, routine first trimester screening for aneuploidy would necessitate the creation of an entirely new protocol for the collection of maternal serum samples and their interpretation, as well as a second round of screening for open fetal defects during the early second trimester. In contrast, an advantage of the current protocols is that screening for both types of abnormalities is possible using the same serum sample. Although research may eventually demonstrate that first trimester screening is technically feasible, an evaluation of the logistics of such screening may show it to be impractical. Obstetric implications of elevations and decreases in the new serum markers have not yet been studied carefully. It is logical, however, that just as with abnormal AFP (not explainable on a genetic basis), extreme levels of uE3 and hCG may also be associated with particular obstetric problems. Information on such deviations in analyte levels is just beginning to emerge. Finally, the study of maternal serum markers may contribute to an understanding of placental function in the second trimester, and ultimately advance our understanding of the underlying pathophysiologies of various fetal chromosomal and morphologic defects.(ABSTRACT TRUNCATED AT 400 WORDS)

HIV Seropositivity among Female Prostitutes and Nonprostitutes: Obstetric and Perinatal Implications

Serum samples totaling 600 were obtained from female prostitutes (300) resident in different hotels in Lagos, Nigeria and nonprostitutes (300) attending different health centers for routine check-up in Lagos, Nigeria. Sera obtained were screened for the prevalence of HIV seropositivity among prostitutes in comparison with nonprostitutes by the enzyme linked immunosorbent assay (ELISA) using the Abbott test kits as recommended by the manufacturers. Positive sera were subjected to confirmatory testing using the Western Blot test-New Lav Blot I and II. Our results revealed that of the 300 prostitutes and nonprostitutes screened, 50 (16.67%) and 6 (2%) were HIV seropositive, respectively, and the difference was statistically significant (P < 0.01). For antibody to HIV-1, 44 (88%) and 5 (83%) of the positive cases recorded among prostitutes and nonprostitutes were seropositive. Four (8%) and one (16.67%) of the positive cases were HIV-2 seropositive for prostitutes and nonprostitutes, respectively. Only 2 (4%) of the positive samples from prostitutes showed reactivities with HIV-1 and HIV-2 (simultaneous infection or dual reactivity). Incidence of the dual reactivity was not recorded among the nonprostitutes screened. This study is expected to provide baseline data on HIV seropositivities among prostitutes and nonprostitutes in Nigeria. The biomedical application of this study is that it will also serve as strong evidence to indicate the high prevalence of HIV seropositivity among prostitutes in order to attract government intervention to step-up control measures.