Urinary stress incontinence and other maternal outcomes 2 years after caesarean or vaginal birth for twin pregnancy: a multicentre randomised trial

OBJECTIVE

Does planned caesarean compared with planned vaginal birth lower the risk of problematic urinary stress, faecal, or flatal incontinence?

DESIGN

Women between 32^0/7 and 38^6/7 weeks of gestation with a twin pregnancy were randomised to planned caesarean or planned vaginal birth.

SETTING

The trial took place at 106 centres in 25 countries.

POPULATION

A total of 2305 of the 2804 women enrolled in the study completed questionnaires at 2 years (82.2% follow-up): 1155 in the planned caesarean group and 1150 in the planned vaginal birth group.

METHODS

A structured self-administered questionnaire completed at 2 years postpartum.

MAIN OUTCOME MEASURES

The primary maternal outcome of the Twin Birth Study was problematic urinary stress, or fecal, or flatal incontinence at 2 years RESULTS: Women in the planned caesarean group had lower problematic urinary stress incontinence rates compared with women in the planned vaginal birth group [93/1147 (8.11%) versus 140/1143 (12.25%); odds ratio, 0.63; 95% confidence interval, 0.47-0.83; P = 0.001]. Among those with problematic urinary stress incontinence, quality of life (measured using the Incontinence Impact Questionnaire, IIQ-7) was not different for planned caesarean versus planned vaginal birth groups [mean (SD): 18.4 (21.0) versus 19.1 (21.5); P = 0.82]. There were no differences in problematic faecal or flatal incontinence, or in other maternal outcomes.

CONCLUSIONS

Among women with a twin pregnancy and no prior history of urinary stress incontinence, a management strategy of planned caesarean compared with planned vaginal birth reduces the risk of problematic urinary stress incontinence at 2 years postpartum. Our findings show that the prevalence but not the severity of urinary stress incontinence was associated with mode of birth.

FUNDING

Canadian Institutes of Health Research (CIHR) (grant no. MCT-63164).

TWEETABLE ABSTRACT

For women with twins, planned caesarean compared with planned vaginal birth is associated with decreased prevalence but not severity of urinary stress incontinence at 2 years.

Maternal outcomes at 3 months after planned caesarean section versus planned vaginal birth for twin pregnancies in the Twin Birth Study: a randomised controlled trial

OBJECTIVE

To compare outcomes at 3 months post partum for women randomised to give birth by planned caesarean section (CS) or by planned vaginal birth (VB) in the Twin Birth Study (TBS).

DESIGN

We invited women in the TBS to complete a 3-month follow-up questionnaire.

SETTING

Two thousand and eight hundred and four women from 25 countries.

POPULATION

Two thousand and five hundred and seventy women (92% response rate).

METHODS

Women randomised between 13 December 2003 and 4 April 2011 in the TBS completed a questionnaire and outcomes were compared using an intention-to-treat approach.

MAIN OUTCOME AND MEASURES

Breastfeeding, quality of life, depression, fatigue and urinary incontinence.

RESULTS

We found no clinically important differences between groups in any outcome. In the planned CS versus planned VB groups, breastfeeding at any time after birth was reported by 84.4% versus 86.4% (P = 0.13); the mean physical and mental Short Form (36) Health Survey (SF-36) quality of life scores were 51.8 versus 51.6 (P = 0.65) and 46.7 versus 46.0 (P = 0.09), respectively; the mean Multidimensional Assessment of Fatigue score was 20.3 versus 20.8 (P = 0.14); the frequency of probable depression on the Edinburgh Postnatal Depression Scale was 14.0% versus 14.8% (P = 0.57); the rate of problematic urinary incontinence was 5.5% versus 6.4% (P = 0.31); and the mean Incontinence Impact Questionnaire-7 score was 20.5 versus 20.4 (P = 0.99). Partner relationships, including painful intercourse, were similar between the groups.

CONCLUSION

For women with twin pregnancies randomised to planned CS compared with planned VB, outcomes at 3 months post partum did not differ. The mode of birth was not associated with problematic urinary incontinence or urinary incontinence that affected the quality of life. Contrary to previous studies, breastfeeding at 3 months was not increased with planned VB.

TWEETABLE ABSTRACT

Planned mode of birth for twins doesn't affect maternal depression, wellbeing, incontinence or breastfeeding.

Validity of autism diagnoses using administrative health data

It is necessary to monitor autism prevalence in order to plan education support and health services for affected children. This study was conducted to assess the accuracy of administrative health databases for autism diagnoses. Three administrative health databases from the province of Nova Scotia were used to identify diagnoses of autism spectrum disorders (ASD): the Hospital Discharge Abstract Database, the Medical Services Insurance Physician Billings Database and the Mental Health Outpatient Information System database. Seven algorithms were derived from combinations of requirements for single or multiple ASD claims from one or more of the three administrative databases. Diagnoses made by the Autism Team of the IWK Health Centre, using state-of-the-art autism diagnostic schedules, were compared with each algorithm, and the sensitivity, specificity and C-statistic (i.e. a measure of the discrimination ability of the model) were calculated. The algorithm with the best test characteristics was based on one ASD code in any of the three databases (sensitivity=69.3%). Sensitivity based on an ASD code in either the hospital or the physician billing databases was 62.5%. Administrative health databases are potentially a cost efficient source for conducting autism surveillance, especially when compared to methods involving the collection of new data. However, additional data sources are needed to improve the sensitivity and accuracy of identifying autism in Canada.

Diabetes mellitus following gestational diabetes: role of subsequent pregnancy

OBJECTIVE

This study was designed to determine the rate of diabetes up to 13 years after pregnancies complicated by gestational diabetes and to identify risk factors for developing diabetes. The role of a subsequent pregnancy, with and without gestational diabetes, was also examined.

DESIGN

This was a retrospective cohort study of women with gestational diabetes.

POPULATION AND SETTING

Women who had gestational diabetes in their first pregnancy between 1989 and 2002 were identified through a population-based perinatal database in Nova Scotia, Canada.

METHODS

Subsequent diagnoses of diabetes, up to 13 years after the first pregnancy, were obtained from physician billing and hospital discharge databases. Cox proportional hazards regression models were used to estimate adjusted relative risks (RR) and 95% confidence intervals.

MAIN OUTCOME MEASURES

Diagnosis of diabetes after pregnancy.

RESULTS

Of the 1401 nulliparous women with gestational diabetes, 251 women (17.9%) developed diabetes in the follow-up period. The cumulative incidence at 1, 5, and 10 years was 5.9, 14.8, and 22.2%, respectively. Factors significantly associated with an increased risk of developing diabetes mellitus included a pre-pregnancy weight of > or = 86 kg (RR = 1.8, 95% CI 1.2-2.9), insulin therapy during the index pregnancy (RR = 4.1, 95% CI 2.1-7.9), neonatal hypoglycaemia (RR = 2.6, 95% CI 1.6-4.2), and a subsequent pregnancy with gestational diabetes (RR = 2.3, 95% CI 1.6-3.4).

CONCLUSION

Indicators of the severity of gestational diabetes, defined by insulin use, neonatal hypoglycaemia, and recurrent gestational diabetes in a subsequent pregnancy, are important in predicting a subsequent diagnosis of diabetes. Our findings do not support the theory that subsequent pregnancy, per se, increases the risk of developing diabetes.

Haloacetic acids in drinking water and risk for stillbirth

BACKGROUND

Trihalomethanes (THMs) occurring in public drinking water sources have been investigated in several epidemiological studies of fetal death and results support a modest association. Other classes of disinfection by-products found in drinking water have not been investigated.

AIMS

To investigate the effects of haloacetic acid (HAA) compounds in drinking water on stillbirth risk.

METHODS

A population based case-control study was conducted in Nova Scotia and Eastern Ontario, Canada. Estimates of daily exposure to total and specific HAAs were based on household water samples and questionnaire information on water consumption at home and work.

RESULTS

The analysis included 112 stillbirth cases and 398 live birth controls. In analysis without adjustment for total THM exposure, a relative risk greater than 2 was observed for an intermediate exposure category for total HAA and dichloroacetic acid measures. After adjustment for total THM exposure, the risk estimates for intermediate exposure categories were diminished, the relative risk associated with the highest category was in the direction of a protective effect, and all confidence intervals included the null value.

CONCLUSIONS

No association was observed between HAA exposures and stillbirth risk after controlling for THM exposures.

A preterm birth prevention project in Nova Scotia, Canada

OBJECTIVE

The Halifax County Preterm Birth Prevention Project was designed to evaluate the effectiveness of a population-based preterm birth (PTB) prevention program in Nova Scotia from January 1995 through June 1997 (n = 10,326).

METHODS

Preterm birth rates, adjusted for risk status and maternal age, were evaluated over time in Halifax County and compared to non-Halifax County parturients in Nova Scotia. Physician participation was evaluated by means of a mailed survey.

RESULTS

There was no appreciable change in the overall (<37 weeks) or early (<34 weeks) PTB rates within or outside Halifax County during the intervention period compared to the preintervention period. Although not significant, the very (<30 weeks) PTB rate in Halifax County decreased by 40% from 0.53 to 0.32%, while outside Halifax County it remained stable (0.43-0.42%). There was a statistically significant decrease in early and very PTB associated with spontaneous labour, as well as an apparent shift in the timing of delivery from very preterm to preterm (> or =30 weeks). Participation among responding physicians was greater for high-risk than low-risk women, but full compliance with project recommendations was low.

CONCLUSION

The overall ineffectiveness of the Halifax County Preterm Birth Prevention Project may reflect the reluctance of practitioners to fully incorporate the recommended prevention strategies into their practice. However, such interventions may reduce the risk of spontaneous early preterm birth.

Causes and consequences of recent increases in preterm birth among twins

OBJECTIVE

To examine the causes and consequences of the recent increase in preterm birth among twins.

METHODS

We studied all twin births among residents of the province of Nova Scotia, Canada, between 1988 and 1997. Rates of preterm birth, preterm labor induction, preterm cesarean, small-for-gestational age (SGA), respiratory distress syndrome (RDS), stillbirth, perinatal mortality, and infant mortality were compared between past and more recent years. Changes in perinatal mortality were examined using logistic regression to adjust for the effects of other determinants.

RESULTS

The study included 2516 twin births (73 stillbirths and 2443 live births). The rate of preterm birth increased from 42.3% in 1988-1992 to 48.2% of twin live births in 1993-1997 (14% increase, P =.04). Twin live births born after preterm labor induction increased from 3.5% in 1988-1989 to 8.6% in 1996-1997 (P for trend =.007). Of live births between 34 and 36 weeks' gestation, the proportion born SGA decreased from 17.5% in 1988-1992 to 9.2% in 1993-1997 (P =.005). Over the same period, rates of prophylactic maternal steroid therapy increased substantially and rates of RDS declined. Perinatal mortality rates among pregnancies reaching 34 weeks decreased from 12.9 per 1000 total births in 1988-1992 to 4.2 per 1000 total births in 1993-1997 (P =.05).

CONCLUSION

Increases in preterm labor induction appear to be responsible for the recent increase in preterm birth among twins. These changes have been accompanied by decreases in perinatal morbidity and mortality among twin pregnancies that reach 34 weeks' gestation.

Rates and risk factors for recurrence of gestational diabetes

OBJECTIVE

To determine the recurrence rate of gestational diabetes (GDM) during a subsequent pregnancy among women who had GDM during an index pregnancy and to identify factors associated with the probability of recurrence

RESEARCH DESIGN AND METHODS

A retrospective longitudinal study was performed in Nova Scotia, Canada, of women who were diagnosed as having GDM during a pregnancy between the years of 1980 and 1996 and who had at least one subsequent pregnancy during this time period. When only the index and first subsequent pregnancy were analyzed, the cohort included 651 women. The recurrence rate of GDM in the pregnancy after the pregnancy with the initial diagnosis of GDM was determined. Multivariate regression models were constructed to model the recurrence of GDM in a subsequent pregnancy as functions of potential predictors to estimate RRs and CIs.

RESULTS

The rate of recurrence of GDM in the pregnancy subsequent to the index pregnancy was found to the 35.6% (95% CI = 31.9-39.3%). Multivariate regression models showed that infant birth weight in the index pregnancy and maternal prepregnancy weight before the subsequent pregnancy were predictive of recurrent GDM.

CONCLUSIONS

In this large cohort of women, slightly more than one-third of the subjects had diabetes in a subsequent pregnancy, which is consistent with recurrence rates in other predominately white populations. Strategies to reduce the occurrence of neonatal macrosomia and maternal prepregnancy obesity may help lower the rate of recurrence of GDM.

Maternal complications with placenta previa

The purpose of this study is to describe the maternal complications of placenta previa. A population-based retrospective cohort study including all women delivered in the province of Nova Scotia, Canada from 1988 to 1995 was performed. Patient information was obtained from the Nova Scotia Atlee Perinatal Database and maternal complications were described for all women undergoing cesarean delivery. Prognostic factors for the risk of hysterectomy in woman with placenta previa were analyzed by multiple logistic regression. During the 8-year period, 308 cases of placenta previa were identified in 93,996 deliveries (0.33%). Maternal complications included hysterectomy [relative risk (RR) = 33.26], antepartum bleeding (RR = 9.81), intrapartum (RR = 2.48), and postpartum (RR = 1.86) hemorrhages, as well as blood transfusion (RR = 10.05), septicemia (RR = 5.55), and thrombophlebitis (RR = 4.85). Risk factors for need of hysterectomy in women with placenta previa include the presence of placenta accreta and previous cesarean delivery.

Technical factors in early amniocentesis predict adverse outcome. Results of the Canadian Early (EA) versus Mid-trimester (MA) Amniocentesis Trial

The purpose of this study was to identify risk factors for fetal loss and other pregnancy complications associated with genetic amniocentesis. Data were acquired in the Canadian Early Amniocentesis Trial (CEMAT), a multicentered (12) prospective, randomized trial comparing continuous ultrasound-guided early amniocentesis (EA) and mid-trimester amniocentesis (MA) (CEMAT Group, 1998). Details of the procedure were recorded and analysed by allocation (EA versus MA), operator and centre, and correlated with pregnancy outcome. A total of 62 spontaneous pregnancy losses occurred between the procedure and 20 weeks' gestation among the 3691 patients who received their procedures within the allocated window (EA=53/1916, MA=9/1775). Technical factors correlating with these losses included procedures 'judged to be difficult' by the operator, and post-procedure amniotic fluid leakage or bleeding. Maternal risk factors included maternal hypertension (fetal loss 11. 1 per cent, compared with non-hypertensive women, 2.6 per cent) increased body mass index (BMI) and gravidity of three or greater. Allocation to EA was predictive of fetal loss, as well as failed procedure, multiple needle insertions, amniotic fluid leakage, failed culture and talipes equinovarus, in excess compared with MA. In conclusion, in this large prospective randomized trial evaluating amniocentesis, specific maternal, fetal and procedural variables were found to be predictive of fetal loss and adverse pregnancy outcome. Performing amniocentesis before 13 weeks' gestation (EA) was the major predictive factor for adverse outcome. These data suggest that first-trimester chorionic villus sampling (CVS) and MA will likely remain the invasive procedures of choice for evaluation of fetal karyotype.

Risk scoring, fetal fibronectin, and bacterial vaginosis to predict preterm delivery

OBJECTIVE

To determine the value of markers for predicting spontaneous preterm birth.

METHODS

One hundred forty asymptomatic gravidas were recruited from 20-24 weeks' gestation. Risk score was assessed, vaginal swabs were analyzed for bacterial vaginosis, and cervical and vaginal swab were tested for fetal fibronectin FDC-6, X18A4, and CAF. Univariate analysis was used to determine potential predictors (and combinations of predictors) of outcome. Multiple logistic regression was done to identify independent predictors of spontaneous preterm birth. Sensitivity, specificity, positive and negative predictive values; and odds and likelihood ratios were calculated for significant predictors.

RESULTS

Predictors significantly associated with the primary outcome were preterm birth-risk score and vaginal fetal fibronection FDC-6 (logistic regression odds ratio [OR] 16.9 [95% confidence interval (CI) 3.1, 92.8]) and 8.0 ([95% CI 1.6, 38.2], respectively). Bacterial vaginosis, fetal fibronectin X18A4, fibronectin CAF, and cervical fetal fibronectin FDC-6 were not associated with spontaneous preterm birth; however, the statistical power to assess these variables was limited. The combination of positive preterm birth-risk score and vaginal fetal fibronectin FDC-6 had a sensitivity of 44.4%, specificity of 97.7%, positive predictive value of 57.1%, negative predictive value of 96.2%, and a significant likelihood ratio for a positive test of 19.4 (95% CI 5.1, 73.8).

CONCLUSION

The combination of preterm birth-risk score and vaginal fetal fibronectin FDC-6 predicted spontaneous preterm birth. Intervention trials are required to determine whether a combination of screening tests will reduce rates of spontaneous preterm birth.

Neonatal outcomes with placenta previa

OBJECTIVE

To identify neonatal complications associated with placenta previa.

METHODS

This was a population-based, retrospective cohort study involving all singleton deliveries in Nova Scotia from 1988 to 1995. The study group consisted of all completed singleton pregnancies complicated by placenta previa; all other singleton pregnancies were considered controls. Patient information was collected from the Nova Scotia Atlee perinatal database. Neonatal complications were evaluated while controlling for potential confounders. The data were analyzed using chi2, Fisher exact test, and multiple logistic regression.

RESULTS

Among 92,983 pregnancies delivered during the study period, 305 cases of placenta previa were identified (0.33%). After controlling for potential confounders, neonatal complications significantly associated with placenta previa included major congenital anomalies (odds ratio [OR] 2.48), respiratory distress syndrome (OR 4.94), and anemia (OR 2.65). The perinatal mortality rate associated with placenta previa was 2.30% (compared with 0.78% in controls) and was explained by gestational age at delivery, occurrence of congenital anomalies, and maternal age. Although there was a higher rate of preterm births in the placenta previa group (46.56% versus 7.27%), there was no difference in birth weights between groups after controlling for gestational age at delivery.

CONCLUSION

Neonatal complications of placenta previa included preterm birth, congenital anomalies, respiratory distress syndrome, and anemia. There was no increased occurrence of fetal growth restriction.

Perinatal outcomes in women with asthma during pregnancy

OBJECTIVE

To determine whether adverse perinatal outcome is associated with asthma or asthma medication use during pregnancy.

METHODS

A retrospective cohort study was conducted of women who resided in Halifax County, Nova Scotia, and delivered between 1991 and 1993. Asthmatic women were classified into three groups, according to medication usage: no medications, beta agonists only, and steroids with or without other asthma medications. Outcomes compared among asthmatic and nonasthmatic women included maternal complications (pregnancy-induced hypertension, cesarean delivery, gestational diabetes, preterm birth, and antepartum and postpartum hemorrhage) and neonatal outcomes (low birth weight, congenital malformations, hyperbilirubinemia, and respiratory distress syndrome).

RESULTS

The cohort included 817 asthmatic women and 13,709 nonasthmatic women. Overall, the prevalence of pregnancies complicated by asthma increased from 4.8% in 1991 to 6.9% in 1993. Asthmatic women were at increased risk for antepartum and postpartum hemorrhage, independent of medication usage. Asthmatic women taking steroids were at increased risk for pregnancy-induced hypertension (odds ratio [OR] 1.7; 95% confidence interval [CI] 1.0, 2.9). The only significant difference in neonatal outcome between asthma medication groups and nonasthmatic women was of an increased risk of hyperbilirubinemia in infants of women taking steroids (OR 1.9; 95% CI 1.1, 3.4).

CONCLUSION

Risk of antepartum and postpartum hemorrhage is increased in asthmatic women, independent of medication usage. The increased incidence of neonatal hyperbilirubinemia and the borderline increased risk of pregnancy-induced hypertension may be complications of steroid use or may be related to poorly controlled asthma.

Transvaginal ultrasound in the prediction of preterm delivery: singleton and twin gestations

OBJECTIVE

To compare, in singleton and twin pregnancies, the effectiveness of transvaginal ultrasound versus digital examination in predicting preterm delivery in women with suspected preterm labor.

METHODS

Transvaginal ultrasound and pelvic examinations were performed on patients admitted with suspected preterm labor between 23 and 33 weeks' gestation. Ultrasound assessment of cervical length and the presence of funneling with fundal pressure were recorded for each patient, and the results were compared with dilatation and effacement as assessed by digital examination for the prediction of preterm delivery in the two groups (singletons and twins).

RESULTS

One hundred sixty-two subjects were recruited (136 singletons and 26 twin pregnancies), with no significant demographic differences between the groups. Overall, 33% of the participants delivered preterm (27% of singletons, 62% of twins). Using receiver operating characteristics curves, the best cutoff points were 30 mm for endocervical length at ultrasound, 50% for effacement, and 1.5 cm for dilatation. Of these, the best predictor was endocervical length, which was a better predictor in singleton than in twin pregnancies. Of the potential predictors, including endocervical length, funneling, dilatation, and effacement, only endocervical length was an independent predictor of preterm delivery at less than 34 weeks' gestation for both singletons and twins by multiple logistic regression. When analyzed for delivery at less than 37 weeks' gestation, this relation held true for singletons but not twins. Endocervical length less than 30 mm had a sensitivity of 81% and 75%, specificity of 65% and 30%, positive predictive value of 46% and 63%, and negative predictive value of 90% and 43% for singleton and twin pregnancies, respectively, in predicting spontaneous birth at less than 37 weeks' gestation.

CONCLUSION

Between 23 and 33 weeks' gestation, transvaginal ultrasound assessment of endocervical length is superior to funneling and digital examination in predicting preterm delivery in patients who present with suspected preterm labor, and is a better predictor in singletons than in twins.

Seroprevalence of HIV infection in childbearing women in Nova Scotia

OBJECTIVE

To determine the prevalence of HIV-1 infection in childbearing women in Nova Scotia.

DESIGN

An anonymous, unlinked seroprevalence study using "leftover" cord bloods. The study was done in 2 stages: I-Halifax Co. women delivering between February 1, 1992 and December 31, 1993; II-non-Halifax Co. women delivering between November 15, 1993 and December 15, 1994.

RESULTS

Of 9,115 deliveries during stage I and 5,515 during stage II, specimens were tested from 8,864 (97.2%) and 5,219 (95%) respectively. Halifax Co. women were older, more often married and more often reported a STD than the non-Halifax Co. participants with 20% under age 20 reporting a history of STD. There was one EIA and WB positive result among Halifax Co. women (seroprevalence 1/10,000; 95% CI 0.03-6.29) and one EIA positive, WB indeterminant result among non-Halifax Co. women (seroprevalence 0/10,000; 95% CI 0-5.7).

CONCLUSION

There is a low prevalence of HIV infection among Nova Scotia childbearing women. However, a substantial number, especially those < age 20, reported a history of STD.

Is Canada's sex ratio in decline?

In this issue (see pages 37 to 41) Dr. Bruce B. Allan and associates report a small but statistically significant decrease--of about 0.2%--in the proportion of male live births in Canada over the period 1970-90. In this editorial, factors that have been reported in the literature to influence sex ratio are examined within a Canadian context. The authors suggest that although the reasons for the apparent decline in the sex ratio in Canada are unclear, the increasing use of ovulation induction may be a contributing factor. Data from the Nova Scotia Atlee Perinatal Database are discussed with a view to explaining the trend observed in Atlantic Canada, but no obvious explanation emerges. The authors argue that when the period of observation is extended no overall change in the sex ratio is apparent. This would suggest a tendency toward stabilization rather than decline.

Evaluation of maternal fluid dynamics during tocolytic therapy with ritodrine hydrochloride and magnesium sulfate

OBJECTIVE

The purpose of the study was to observe and compare the effects of ritodrine hydrochloride and magnesium sulfate on maternal fluid dynamics.

STUDY DESIGN

Fourteen women in preterm labor were prospectively studied during tocolytic therapy with either ritodrine hydrochloride or magnesium sulfate. The cardiovascular and renal effects of a pretreatment crystalloid infusion were compared with those observed during tocolytic therapy. Profile analysis and repeated measures of variance were used to analyze the data.

RESULTS

Ritodrine hydrochloride was associated with decreased colloid osmotic pressure, hematocrit, and serum proteins and increased maternal and fetal heart rates. Arginine vasopressin levels increased during the first 2 hours of therapy, then returned to baseline. Sodium excretion was reduced and there was marked fluid retention. Intravenous magnesium sulfate also resulted in a reduction of colloid osmotic pressure, but hematocrit, serum protein concentration, arginine vasopressin, maternal and fetal heart rates, and mean arterial pressure were minimally affected. Sodium excretion increased to a maximum at 6 to 8 hours of treatment, then returned to baseline. A positive fluid balance was also noted in magnesium sulfate-treated patients but to a lesser degree than with ritodrine.

CONCLUSIONS

Sodium retention appears to be the primary cause of plasma volume expansion in ritodrine-treated patients, whereas volume expansion during magnesium sulfate therapy is probably related to intravenous overhydration. In the absence of risk factors for pulmonary capillary membrane injury, available evidence supports volume overload as the principal mechanism for pulmonary edema during tocolytic therapy.

Spontaneous small bowel obstruction associated with a spontaneous triplet gestation. A case report

Spontaneous bowel obstruction in pregnancy is a rare event and usually associated with a prior history of surgical procedures or infection. Its symptoms can mimic physiologic changes in pregnancy or preterm labor. We treated a woman who had a triplet gestation and whose lack of predisposing factors delayed the diagnosis of obstruction. The patient delivered prematurely at 22 weeks and required surgery to alleviate the obstruction. The possibility of intestinal obstruction should be entertained in any pregnant woman presenting with nausea, vomiting and an overdistended uterus.

Molecular detection of a Yp/18 translocation in a 45,X holoprosencephalic male

Prenatal diagnosis in a fetus with holoprosencephaly showed a 45,X karyotype and a suspected 18p abnormality. At birth, the fetus presented with normal male genitalia. Y chromatin was not cytogenetically detectable by Q-, G-, or G11-banding. Mosaicism for a cell line containing a Y chromosome was not observed in amniocytes, lymphocytes, or skin fibroblasts. Southern blot analysis for 11 different Y-DNA loci demonstrated the presence in the patient's genome of sequences derived from the short arm, centromeric region, and proximal long arm of the Y chromosome (intervals 1-5). The distal long arm of the Y (intervals 6 and 7) was absent. In situ hybridization with the Y-derived probe pDP105 showed silver grains over the short arm of the del(18) chromosome, suggesting a Y/18 translocation with loss of 18p and distal Yq material.