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R Mittendorf

Publications and source records attributed to R Mittendorf.

13 recordsLinked to original sources

Cigarettes, coffee, and preterm premature rupture of the membranes.

Premature (prior to 37 completed weeks of gestation) rupture of the membranes (preterm PROM) is one of the most common underlying causes of preterm delivery. However, there have been few epidemiologic studies of this obstetric complication. The authors studied the relation of maternal cigarette smoking and coffee consumption to both preterm PROM and spontaneous preterm labor not complicated by premature rupture of the membranes (preterm NONPROM) in a large cross-sectional data base. The 307 preterm PROM and 488 preterm NONPROM cases who delivered during 1977-1980 at the Boston Hospital for Women were compared with 2,252 randomly selected women who delivered at term at that institution. Multiple logistic regression techniques were used to derive maximum likelihood estimates of adjusted odds ratios (OR) and 95% confidence intervals (CI). After confounders had been adjusted for, the relative risk of preterm PROM for women who reported ever having smoked during pregnancy, as compared with nonsmokers, was 1.6 (95% CI 1.1-2.4). However, no gradient between the number of cigarettes smoked per day and the risk of preterm PROM was observed. Similar results were observed for preterm NONPROM. Women who consumed three or more cups of coffee daily during the first trimester had a 2.2-fold greater risk of preterm PROM than did women who drank two or fewer cups (95% CI 1.5-3.3). Among coffee drinkers, there was some evidence of a linear trend in the risk of preterm PROM as coffee consumption increased. Consumption of three or more cups of coffee per day was less strongly associated with the occurrence of preterm NONPROM (adjusted OR = 1.4, 95% CI 1.0-1.9).

Adolescent

Prevention of preterm delivery and low birth weight associated with asymptomatic bacteriuria.

Since the first report of an association between asymptomatic bacteriuria and low birth weight (less than 2,500 g) in 1962, greater than 30 other studies on the same subject have been published. Some of these confirmed this association while others disputed it. Now, however, by using meta-analysis (a technique considered valid by many but not all statisticians) one may conclude with increased certainty that true associations between asymptomatic bacteriuria and preterm delivery (less than 37 weeks of gestation) and asymptomatic bacteriuria and low birth weight do exist. Because asymptomatic bacteriuria in pregnancy remains prevalent and preventable, a review of this important subject is relevant at this time.

Bacteriuria

The reliability of self-reported alcohol consumption in the remote past.

We examined the reliability of self-reported alcohol consumption in past age periods of women's lives. As part of a case-control study of breast cancer conducted in Massachusetts and Wisconsin in 1988-1991, the same questionnaire was administered for a second time to 211 controls (mean age = 54 years) after an interval of 6-12 months. The Spearman correlation coefficients between the average number of grams of alcohol consumed daily reported in the two interviews, by age period of consumption, were: 16-19 years, r = 0.81; 20-29 years, r = 0.84; 30-39 years, r = 0.75; and for recent consumption, r = 0.77. Self-reported alcohol consumption throughout adult life was reported with precision sufficient to make the ranking of subjects' intake consistent between interviews.

Adult

Low birth weight and preterm delivery in relation to early-gestation vaginal bleeding and elevated maternal serum alpha-fetoprotein.

OBJECTIVE: To determine whether early-gestation vaginal bleeding and elevated maternal serum alpha-fetoprotein (MSAFP) are independent risk factors for adverse infant outcomes. METHODS: We conducted a cohort study of 201 women with an elevated MSAFP (at least 2.0 multiples of the median [MOM]) and a second-trimester ultrasound evaluation at Swedish Hospital Medical Center between January 1989 and March 1991, and 211 women with MSAFP levels below 2.0 MOM who had also undergone ultrasound evaluations during the same period. RESULTS: Stratified analyses demonstrated that early-gestation bleeding and elevated MSAFP were independent risk factors for the delivery of both preterm and low birth weight infants. Compared with women with no history of early-gestation bleeding or elevated MSAFP, women with early-gestation bleeding alone had a relative risk (RR) of preterm delivery of 4.3 (95% confidence interval [CI] 1.5-12.1); non-bleeders with elevated MSAFP had an RR of 4.6 (95% CI 1.9-10.9). A combined history of early-gestation bleeding and elevated MSAFP was associated with an almost sixfold increased risk of preterm delivery (RR 5.8; 95% CI 2.2-15.6). Analyses restricted to women with normal-appearing appearing placentas by second-trimester ultrasound evaluations yielded similar results. CONCLUSIONS: These findings support an earlier report documenting the independence of early-gestation bleeding and elevated MSAFP as predictors of adverse infant outcomes.

Cohort Studies

Risk factors for abruptio placentae.

The authors studied the relation of sociodemographic, medical, and life-style factors and abruptio placentae in a large cross-sectional data base. The 143 cases of abruption identified in the Delivery Interview Program, conducted in Boston from 1977 to 1980, were compared with 1,257 randomly selected controls. The authors used multiple logistic regression techniques to derive maximum likelihood estimates of the adjusted odds ratios and 95% confidence intervals as measures of the association between exposure factors and abruption. A history of chronic hypertension was associated with a threefold increase in risk (odds ratio (OR) = 3.1, 95% confidence interval (Cl) 1.1-8.4), but pregnancy-induced hypertension was not associated with abruption. Excess risk was associated with advanced maternal age (OR = 2.3, 95% Cl 1.3-3.9), low prepregnancy body mass index (OR = 2.3, 95% Cl 1.3-4.1), a history of prior stillbirth (OR = 3.5, 95% Cl 1.8-7.0), and at least weekly use of marijuana during pregnancy (OR = 2.8, 95% Cl 1.2-6.6). Overall, the association with cigarette smoking during pregnancy was of only borderline significance (OR = 1.5, 95% Cl 1.0-2.2), although there appeared to be a dose-response relation between the number of cigarettes smoked and risk of abruption.

Abruptio Placentae

Cigarette smoking during pregnancy in relation to placenta previa.

To evaluate the relationship between cigarette smoking and the occurrence of placenta previa, we used interview and medical record data to conduct a case-control analysis of 69 placenta previa cases and 12,351 controls. The unadjusted relative risk estimate of placenta previa for women reported to have "ever smoked" during pregnancy relative to nonsmoking mothers was 1.9 (95% confidence interval, 1.2 to 3.0). The risk rose after adjusting for potential confounders (odds ratio, 2.6; 95% confidence interval, 1.3 to 5.5). In contrast to a previous report, the duration of smoking was not an independent risk factor for placenta previa. These results suggest that cigarette smoking during pregnancy is a determinant of placenta previa. Carbon monoxide hypoxemia, which is one possible mechanism for this association, may result in compensatory placental hypertrophy. Placentas with increased surface areas are more likely to cover the cervical os, causing placenta previa.

Adult

A rapid visual test for predicting fetal lung maturity.

A rapid bedside test has been devised that enables an untrained observer to predict (p less than 0.001) when amniotic fluid will be greater than or equal to 0.15 at an optical density of 650 nm, lecithin/sphingomyelin ratio will be greater than or equal to 2.0, or when phosphatidylglycerol will be present. By a visual comparison of the turbidity of unspun amniotic fluid against positive (mature) or negative (immature) controls, technicians and resident physicians who had had no special training were able to classify correctly 87.2% (82/94) of unknown amniotic fluid samples. The sensitivity of the new test is 90.8% (58/65); the specificity is 70.3% (23/29). Thus, when more sophisticated methods are not readily available, we believe that this easily performed and accurate test can provide supplemental or preliminary data for patient management. In remote geographic areas our method could serve as the primary source of information about fetal lung maturity.

Amniotic Fluid

Subfertility and the risk of low birth weight.

OBJECTIVE: We evaluated the association between subfertility and low birth weight infants. DESIGN: Women in this analysis participated in a cross-sectional investigation of maternal risk factors for adverse pregnancy outcomes. SETTING: Medical and obstetric history and life style information were obtained from women who delivered at the Boston Hospital for Women, 1977 to 1980. PATIENTS, PARTICIPANTS: Our analysis was restricted to nondiabetic married women who planned their pregnancies and subsequently delivered viable singletons (3,622). The 644 "subfertile" women (no conception during a year of unprotected intercourse) were compared with 2,978 "fertile" women (conception within 1 year). MAIN OUTCOME MEASURE(S): The relative risk of low birth weight was estimated using the cumulative incidence risk ratio. RESULTS: After adjusting for confounding, the relative risk of delivering a low birth weight infant (less than 2,500 g) for subfertile women versus fertile women was 1.9 (95% confidence interval [CI], 1.3 to 2.8). The adjusted relative risk of delivering a term low birth weight (intrauterine growth retarded) infant was 2.3 (95% CI, 1.2 to 4.4). CONCLUSIONS: In these data, subfertility is a predictor for low birth weight. The association may result from endocrinological, immunological, cervical, or other factors that interfere with optimal fetal growth.

Coffee

Chronic hypertension, cigarette smoking, and abruptio placentae.

We investigated the importance of maternal hypertension and cigarette smoking, and their interaction, as risk factors for abruptio placentae, using Massachusetts birth certificate data for 1987-1988. We used multiple logistic regression procedures to model data from 943 abruptio placentae cases and 10,648 randomly selected births. Risk of abruption was associated with a history of chronic hypertension (adjusted OR = 2.3, 95% CI: 1.5-3.5) and cigarette smoking during pregnancy (adjusted OR = 1.7, 95% CI: 1.5-2.0). There was also evidence of interaction between chronic hypertension and cigarette smoking. The hypoxemia that results from exposure to cigarette smoke and the alterations in uterine blood flow that result from hypertension may lead to placental lesions that cause abruption.

Abruptio Placentae

Rho(D) immunoglobulin (RhoGAM): how it came into being.

The story of Rho(D) immunoglobulin (RhoGAM) begins in 1909 with Theobald Smith, Fabyan Professor of Comparative Pathology at Harvard, and ends in the 1960s with completion of the clinical trials. Important in the development of RhoGAM were the search for a safe diphtheria vaccine, an interest in butterfly mimicry, the discovery of the Rhesus factor, and the contribution of Sing Sing prison inmates--seemingly unrelated occurrences. But, when all were combined, the riddle of erythroblastosis fetalis was solved.

Diphtheria Toxoid

Adverse infant outcomes associated with first-trimester vaginal bleeding.

We assessed the association between first-trimester vaginal bleeding and singleton infant outcomes in a hospital-based population of 11,444 nondiabetic women. Low birth weight (LBW), shortened gestation, LBW at term, and neonatal death occurred more often in women reporting first-trimester bleeding than in those who never bled. These relationships remained statistically significant after adjusting for confounding factors. Women who experienced vaginal bleeding limited to the first trimester (N = 1174) had double the risk of delivering a preterm infant compared with those experiencing no bleeding (adjusted risk ratio = 2.0; 95% confidence interval 1.6-2.5). Bleeding limited to the first trimester was associated with a 1.6-fold risk of delivery of a term LBW infant (95% confidence interval 1.3-2.0). These results suggest that first-trimester vaginal bleeding is an important correlate of adverse infant outcomes.

Adult

The length of uncomplicated human gestation.

By retrospective exclusion of gestations with known obstetric complications, maternal diseases, or unreliable menstrual histories, we found that uncomplicated, spontaneous-labor pregnancy in private-care white mothers is longer than Naegele's rule predicts. For primiparas, the median duration of gestation from assumed ovulation to delivery was 274 days, significantly longer than the predicted 266 days (P = .0003). For multiparas, the median duration of pregnancy was 269 days, also significantly longer than the prediction (P = .019). Moreover, the median length of pregnancy in primiparas proved to be significantly longer than that for multiparas (P = .0032). Thus, this study suggests that when estimating a due date for private-care white patients, one should count back 3 months from the first day of the last menses, then add 15 days for primiparas or 10 days for multiparas, instead of using the common algorithm for Naegele's rule.

Female