Trends in twin birth outcomes and prenatal care utilization in the United States, 1981-1997

CONTEXT: Multiple births account for an increasing percentage of all low-birth-weight infants, preterm births, and infant mortality in the United States. Since 1981, the percentage of women with multiple births who received intensive prenatal care (defined as a high number of visits, exceeding the recommendation of the American College of Obstetricians and Gynecologists by approximately 1 SD beyond the mean number of visits for women initiating care within each trimester) has increased significantly. OBJECTIVES: To explore the hypothesis that more aggressive management of twin-birth pregnancies may be associated with changes in birth outcomes in this population. DESIGN, SETTING, AND SUBJECTS: Cross-sectional and trend analysis of data from the National Center for Health Statistics' birth and infant death records for all twin births occurring in the United States between 1981 and 1997, excluding those with missing or inconsistent data. MAIN OUTCOME MEASURES: Trends in preterm birth, low birth weight, preterm and term small-for-gestational-age (SGA) births, and infant mortality, by level of prenatal care utilization. RESULTS: The preterm birth rate for twins increased from 40.9% in 1981 to 55.0% in 1997. The percentage of low-birth-weight infants increased from 51.0% to 54.0%. The preterm SGA rate also increased from 11.9% to 14.1%, while the term SGA rate decreased from 30.7% to 20.5%. For women with intensive prenatal care utilization, the preterm birth rate increased from 35.1% to 55.8%, compared with an increase from 50.6% to 59.2% among women with only adequate use. Twin preterm deliveries involving either induction or first cesarean delivery also increased from 21.9% to 27.3% between 1989-1991 and 1995-1997. The twin infant mortality rate for women with intensive prenatal care use declined between 1983 and 1996 and remained lower than the overall twin infant mortality rate. CONCLUSIONS: An apparent increase in medical interventions in the management of twins may result in the seeming incongruity of more prenatal care and more preterm births; however, these data suggest that women with intensive prenatal care utilization also have a lower infant mortality rate. JAMA. 2000;283:335-341     

Low birth weight, prematurity, and postpartum endometritis. Association with prenatal cervical Mycoplasma hominis and Chlamydia trachomatis infections

We studied associations of Mycoplasma hominis, Ureaplasma urealyticum, and Chlamydia trachomatis genital infections with pregnancy outcomes, controlling by logistic and multiple linear regression for known risk factors and for the presence of the other two infections. A sample of 1204 Navajo women enrolling for prenatal care had endocervical C trachomatis, M hominis, and U urealyticum cultures and serum samples taken at enrollment and when possible after 30 weeks. Low birth weight (less than 2500 g) was associated with M hominis infection among women with a history of spontaneous abortion. Mycoplasma hominis infection was also associated with postpartum endometritis, but only among women undergoing a cesarean section (odds ratio, 4.7; 95% confidence intervals, 1.22 to 18.3). Although women with recent C trachomatis infection (IgM titer greater than 1:32 on either sample or IgG seroconversion) were at greater risk of low birth weight (19% [3/16]) than women with chronic infection (4.5% [6/133]; relative risk, 4.2), this subgroup at risk was small (11% of women with classifiable C trachomatis infection). Mycoplasma hominis and C trachomatis infections may be important preventable causes of adverse pregnancy outcomes in identifiable subgroups of women.     

Independent associations of bacterial vaginosis and Chlamydia trachomatis infection with adverse pregnancy outcome

We prospectively studied the relationship of pregnancy outcome to bacterial vaginosis, an anaerobic vaginal condition, and to other selected genital pathogens among 534 gravid women. Bacterial vaginosis was presumptively diagnosed by gas-liquid chromatographic identification of microbial organic acid metabolites in 102 women (19%), and cervical infection with Chlamydia trachomatis was found in 47 (9%) of the women. Although women with and without bacterial vaginosis had similar demographic and obstetric factors, neonates born to women with bacterial vaginosis had lower mean birth weight than did neonates born to women without bacterial vaginosis (2960 +/- 847 g vs 3184 +/- 758 g). Bacterial vaginosis was significantly associated with preterm premature rupture of the membranes (odds ratio [OR], 2.0; 95% confidence interval [Cl], 1.1 to 3.7), preterm labor (OR, 2.0; Cl, 1.1 to 3.5), and amniotic fluid infection (OR, 2.7; Cl, 1.1 to 6.1), but not with birth weight below 2500 g (OR, 1.5; Cl, 0.8 to 2.0). Cervical infection with C trachomatis was independently associated with preterm premature rupture of the membranes, preterm labor, and low birth weight (OR, 1.5; Cl, 0.8 to 2.0).     

Transmission of HIV-1 infections from mothers to infants in Haiti. Impact on childhood mortality and malnutrition. The CDS/JHU AIDS Project Team

Of 4588 pregnant women in a high-risk Haitian population, 443 (9.7%) were serologically positive for the human immunodeficiency virus type 1 (HIV-1). Infants born to women who were HIV-1 seropositive were more likely to be premature, of low birth weight, and malnourished at 3 and 6 months of age than were infants born to women who were HIV-1 seronegative. Increased mortality was observed in infants born to women who were HIV-1 seropositive by 3 months of age. At 12 months of age, 23.4% of the infants born to women who were HIV-1 seropositive had died compared with 10.8% of the infants born to women who were HIV-1 seronegative; at 24 months of age, the mortality rates were 31.3% and 14.2%, respectively. Maternal HIV-1 infections resulted in an 11.7% increase in the overall infant mortality rate in this population. The estimated mother-to-infant HIV-1 transmission rate in these breast-fed infants was 25%, similar to the rates reported for non-breast-fed populations in the United States and Europe.     

北京部分郊区279例孕产妇早产相关因素分析

目的 通过对早产孕妇不同的病理因素、生理因素和社会因素的分析,了解北京市部分郊区流动人口孕产妇保健状况,并能够有效的预防早产发生.方法 回顾性分析279例自2004年1月至2008年12月在解放军三○六医院住院分娩的早产孕妇.包括年龄、产次、职业、户口所在地、受教育程度、产检情况、阴道炎病史、是否胎膜早破、是否患绒毛膜羊膜炎等因素与早产的关系.结果 本组病例早产总发生率为5.34%(279/5228).早产有统计学意义(P＜0.05)指标为:绒毛膜羊膜炎、胎膜早破、以细菌性阴道病(BV)为主的阴道炎、未规范产检者、未受过高等教育者及流动人口、经产妇及低于法定婚者.而孕产妇职业因素与早产发生率差异无统计学意义(P＞0.05).结论 无规范产检、受教育程度低、阴道炎、绒毛膜羊膜炎及胎膜早破是早产的危险因素,应针对特殊人群加强孕期教育,并在孕期积极治疗生殖道炎症.

Abstract：

Objective To study the health conditions of pregnant migrant women in some suburban areas of Beijing by comparing a variety of pathological, physiological and social factors and exploring the relevant factors associated with preterm birth so as to prevent effectively preterm birth. Methods A total of 279 cases of pregnancy in preterm birth at out hospital from January 2004 to December 2008 were reviewed.The date of maternal age, parity, prenatal examinations, history of vaginitis, history of chorioamnionitis,premature rupture of membranes, occupation, residing location and education status were recorded. And the relationship between them and preterm birth were analyzed by X2 test. Results The overall incidence of preterm birth was 5.34%. And the following factors had statistically significant differences with premature birth: chorioamnionitis, vaginitis, premature rupture of membranes, a lack of prenatal examinations, low education status, migrant population or maternal parity. However there was no statistical significance ( P ＞0.05) between preterm birth and other factors, such as occupation. Conclusion The incidence of preterm birth is associated with a lack of prenatal examinations, low education status, chorioamnionitis, bacterial vaginitis and premature rupture of membranes. Therefore the migrant women in Beijing should receive targeted education programs during pregnancy. And reproductive tract inflammation should be properly treated.     

沙眼衣原体感染与异位妊娠关系的临床观察

目的探讨血清沙眼衣原体(CT)及其热休克蛋白60(C-HSP60)抗体反应与异位妊娠(EP)的关系.方法检测了47例EP患者(EP组)和46例宫内妊娠妇女(对照组)血清CT抗体.用基因工程的方法重组C-HSP60,以纯化后的C-HSP60蛋白为抗原,采用酶联免疫吸附法,检测了两组妇女血清C-HSP60抗体水平.结果 EP组和对照组血清沙眼衣原体IgG抗体阳性率分别为68.1%和34.8%,两组有显著性差异(P<0.05);EP妇女C-HSP60 IgG抗体阳性率为25.5%,高于对照组阳性率4.3%,两者有显著性差异(P<0.05).在沙眼衣原体血清学阳性妇女中,EP组C-HSP60 IgG抗体阳性率为34.4%,与宫内妊娠组0%(0/16)相比,有显著性差异 (P<0.05).两组在血清沙眼衣原体IgM、C- hsp60IgM抗体水平上皆无显著性差异(P>0.05).结论女性生殖道沙眼衣原体感染是导致EP的重要原因,C-HSP60与其发病机理有非常密切的关系.     

Prevalence of Chlamydia trachomatis and genital mycoplasmas in asymptomatic women.

To establish the prevalence of Chlamydia trachomatis, Mycoplasma hominis and Ureaplasma urealyticum in women attending a family planning and a prenatal clinic in Halifax, cervical swabs were obtained at the time of the first visit from 491 women who had no symptoms of genital infection. Among the women attending the family planning clinic M. hominis occurred in combination with C. trachomatis more frequently than expected (p less than 0.05). It occurred in the absence of U. urealyticum in only a few cases (13% of the occurrences in the family planning clinic and 6% of those in the prenatal clinic). C. trachomatis was significantly more prevalent in women under 25 years of age (p less than 0.04). However, mycoplasmas were as prevalent in women over 30 years as in those under 30. There were no significant differences in the infection rates of the organisms by trimester among pregnant women. More research is necessary for a proper understanding of the role of M. hominis and U. urealyticum in genitourinary infections and pregnancy outcomes.     

Chronic Chlamydia trachomatis infections in infants.

OBJECTIVE.--To study the natural history of Chlamydia trachomatis infections in infants. DESIGN.--Bacteriologic and serologic study of an inception cohort. SETTING.--University of Washington Medical Center, Seattle. PARTICIPANTS.--Twenty-two infants with C trachomatis infections either not treated early in life or recurring after antimicrobial treatment. MAIN OUTCOME MEASURES.--Persistence of infection in various anatomic sites, antibody responses to specific serovars (serologic variants) of C trachomatis, and serovars of isolates from mothers and infants. RESULTS.--The cumulative proportion of infants still infected at the age of 1 year was 35%. Infection persisted in the conjunctiva, nasopharynx, and oropharynx in one child for as long as 866 days (28.5 months), when she was cured by treatment. In none of the infants did serologic tests suggest acquisition of infection other than at birth. Isolates of C trachomatis from mothers and their respective infants were always of the same serovar. CONCLUSIONS.--Many infants infected with C trachomatis at birth remain infected for months or years in the absence of specific antimicrobial therapy. Such infections may be confused with those acquired by sexual abuse.     

The contribution of maternal smoking to preterm birth, small for gestational age and low birthweight among Aboriginal and non-Aboriginal births in South Australia

OBJECTIVES: To determine the contribution of maternal smoking to preterm birth (< 37 weeks' gestation), small for gestational age (SGA, birthweight < 10th percentile for gestational age) and low birthweight (< 2500 g) among Aboriginal and non-Aboriginal births in South Australia. DESIGN: Retrospective cohort analysis of population-based perinatal data. SETTING: The State of South Australia, population 1.5 million. PARTICIPANTS: 36059 women (of whom 851 were Aboriginal women) who had singleton births in 1998-1999. MAIN OUTCOME MEASURES: Relative risks and population-attributable risks of preterm birth, SGA and low birthweight from smoking in the second half of pregnancy, by age and Aboriginality. RESULTS: Aboriginal women had a higher rate of smoking in pregnancy than non-Aboriginal women (57.8% v 24.0% at the first antenatal visit) and high rates for all age groups, while the rates decreased with age among non-Aboriginal women. Heavy smoking increased with age, and Aboriginal women were heavier smokers. Women who smoked had elevated relative risks of preterm birth (1.64), SGA (2.28) and low birthweight (2.52), and all these showed a dose-response relationship. Among Aboriginal (versus non-Aboriginal) births, population-attributable risks were significantly higher for SGA (48% v 21%, and 59% for births to Aboriginal teenagers), low birthweight (35% v 23%) and preterm birth (20% v 11%). CONCLUSIONS: Health promotion programs, with a focus on smoking cessation and reducing uptake of smoking, need to be implemented in an appropriate cultural context, especially among young Aboriginal women. Such a program is being developed in South Australia.     

Prospective study of perinatal transmission of Chlamydia trachomatis

During a five-year period, 262 (4.7%) of 5,531 pregnant women had positive cervical cultures for Chlamydia trachomatis, and 131 of their infants were followed up prospectively to ascertain the outcome of chlamydial exposure during the birth process. Culture-confirmed inclusion conjunctivitis of the newborn was seen in 23 (18%) of the infants. Chlamydial pneumonia was diagnosed in 21 (16%) of the infants at risk. Chlamydia trachomatis was recovered from 47 of the infants (36%), while 79 (60%) showed serologic evidence of infection. Subclinical rectal and vaginal infections were detected in 14% of infants at risk. In our population, 2.8% of newborn infants show serologic evidence of perinatal chlamydial infection and 1.4% develop either chlamydial pneumonia or conjunctivitis. Incidence rates of this magnitude indicate the need for programs aimed at preventing perinatal transmission of C trachomatis.     

Characteristics of pregnant women exposed to cocaine in Toronto between 1985 and 1990.

OBJECTIVE: To determine the characteristics of pregnant women exposed to cocaine. DESIGN: Case-control study. SETTING: Women attending the Motherisk Program, Hospital for Sick Children, Toronto, from September 1985 to March 1990. PATIENTS: All women who had admitted using cocaine before or during pregnancy. Of the two control groups the first comprised women who had admitted using cannabinoids but not cocaine before or during pregnancy and the second those who attended the clinic just before the cocaine case but who had not used illicit drugs. OUTCOME MEASURES: Age, marital status, ethnic background, number of pregnancies, children and elective or spontaneous abortions, socioeconomic status of woman and male partner, alcohol use, cigarette use, frequency of cocaine use and total amount taken. MAIN RESULTS: Of the 1625 women 91 (5.6%) admitted to using cocaine: 86 during the current pregnancy, 3 before the current pregnancy, 1 before planning a pregnancy and 1 during a previous pregnancy. None of the cocaine users were considered to be addicts; only 20% had used the drug more than 10 times. A total of 74 women used cannabinoids only. The mean age of the cocaine users was 27.1 (standard deviation [SD] 5.3) years; this was significantly lower than that of the control subjects (30.5 [SD 5.2] years) (p less than 0.001). More of the cocaine users than of the women in either of the two control groups were single (60% v. 38% and 14%, p less than 0.001). The cannabinoid users had significantly higher parity and the nonusers a significantly lower incidence of elective abortions than the cocaine users. The cocaine users had a significantly lower socioeconomic status than the control subjects (p less than 0.001); similarly, the male partners of the cocaine users had a significantly lower socioeconomic status than the partners of the control subjects (p = 0.001). CONCLUSIONS: Pregnant cocaine users who seek drug counselling represent a unique risk group, with clustering of factors such as alcohol and cigarette use and low socioeconomic status that compound the risk to the fetus. New strategies should be explored to identify such women, especially addicts, in their communities and to urge them to seek counselling and treatment.     

Impact of a collaborative shared antenatal care program for urban Indigenous women: a prospective cohort study

OBJECTIVES: To evaluate the impact of a community-based, collaborative, shared antenatal care intervention (the Mums and Babies program) for Indigenous women in Townsville. DESIGN AND PARTICIPANTS: Prospective cohort study of women attending Townsville Aboriginal and Islander Health Service (TAIHS) for shared antenatal care with a singleton Indigenous birth between 1 January 2000 and 31 December 2003 (456 women; the MB group), compared with a historical control group of 84 women who attended TAIHS for antenatal care before the intervention between 1 January 1998 and 30 June1999, and a contemporary control group of 540 women who had a singleton birth at Townsville Hospital between 1 January 2000 and 30 June 2003, but did not attend TAIHS for antenatal care. INTERVENTION: Integration of previously autonomous service providers delivering shared antenatal care from TAIHS. MAIN OUTCOME MEASURES: Patterns of antenatal visits, proportion of women undertaking key antenatal screening, and perinatal outcomes. RESULTS: The number of Indigenous women who entered the MB program and gave birth at Townsville Hospital rose from 23.8% in 2000 to 61.2% in 2003. The number of antenatal care visits per pregnancy increased from three (interquartile [IQ] range, 2-6) in the historical control group to seven (IQ range, 4-10) in the MB group (P < 0.001). 88% of women in the MB group had at least one ultrasound. About 90% of all women attending for antenatal care were screened for sexually transmitted infections. In the MB group, there was a significant reduction in preterm births compared with the contemporary control group (8.7% v 14.3%, P < 0.01). There was no significant reduction in the prevalence of low birthweight births or perinatal mortality. CONCLUSION: A community-based collaborative approach to shared antenatal care services increased access to antenatal care and was associated with fewer preterm births among Indigenous women in Townsville. The model may be adaptable in other urban centres with multiple antenatal care providers and significant numbers of Indigenous people across Australia.     

Effect of serologic status and cesarean delivery on transmission rates of herpes simplex virus from mother to infant

CONTEXT: Neonatal herpes most commonly results from fetal exposure to infected maternal genital secretions at the time of delivery. The risk of transmission from mother to infant as it relates to maternal herpes simplex virus (HSV) serologic status and exposure to HSV in the maternal genital tract at the time of labor has not been quantified. Furthermore, no data exist on whether cesarean delivery, the standard of care for women with genital herpes lesions at the time of delivery, reduces HSV transmission. OBJECTIVE: To determine the effects of viral shedding, maternal HSV serologic status, and delivery route on the risk of transmission of HSV from mother to infant. DESIGN: Prospective cohort of pregnant women enrolled between January 1982 and December 1999. SETTINGS: A university medical center, a US Army medical center, and 5 community hospitals in Washington State. PATIENTS: A total of 58 362 pregnant women, of whom 40 023 had HSV cultures obtained from the cervix and external genitalia and 31 663 had serum samples tested for HSV. MAIN OUTCOME MEASURE: Rates of neonatal HSV infection. RESULTS: Among the 202 women from whom HSV was isolated at the time of labor, 10 (5%) had neonates with HSV infection (odds ratio [OR], 346; 95% confidence interval [CI], 125-956 for neonatal herpes when HSV was isolated vs not isolated). Cesarean delivery significantly reduced the HSV transmission rate among women from whom HSV was isolated (1 [1.2%] of 85 cesarean vs 9 [7.7%] of 117 vaginal; OR, 0.14; 95% CI, 0.02-1.08; P =.047). Other risk factors for neonatal HSV included first-episode infection (OR, 33.1; 95% CI, 6.5-168), HSV isolation from the cervix (OR, 32.6; 95% CI, 4.1-260), HSV-1 vs HSV-2 isolation at the time of labor (OR, 16.5; 95% CI, 4.1-65), invasive monitoring (OR, 6.8; 95% CI, 1.4-32), delivery before 38 weeks (OR, 4.4; 95% CI, 1.2-16), and maternal age less than 21 years (OR, 4.1; 95% CI, 1.1-15). Neonatal HSV infection rates per 100 000 live births were 54 (95% CI, 19.8-118) among HSV-seronegative women, 26 (95% CI, 9.3-56) among women who were HSV-1-seropositive only, and 22 (95% CI, 4.4-64) among all HSV-2-seropositive women. CONCLUSION: Neonatal HSV infection rates can be reduced by preventing maternal acquisition of genital HSV-1 and HSV-2 infection near term. It can also be reduced by cesarean delivery and limiting the use of invasive monitors among women shedding HSV at the time of labor.     

138例孕妇早产高危因素及母婴结局

【目的】探讨早产的常见危险因素与母婴结局的关系。【方法】回顾性分析138例早产的临床资料,与同期足月分娩的138例相比较,分析引起早产的危险因素,并对不同孕周组的母婴结局进行比较。【结果】胎膜早破、未作产前检查和妊娠期高血压疾病是造成早产的高危因素,与足月组比较差异均有统计学意义（ P ＜0．05）。不同孕周早产组在低体质量儿、新生儿呼吸窘迫综合征、Apgar评分＜7分的比率及新生儿病死率方面比较差异具有显著性（P＜0．05）;而对母亲的影响差异不显著（P＞0．05）。【结论】早产的发生与多种因素相关,胎龄越小、体质量越轻,其病死率和并发症越高;加强孕期保健,重视产前检查对新生儿结局意义重大。     

Prevalence of gestational diabetes mellitus among Swampy Cree women in Moose Factory, James Bay

BACKGROUND: Although high rates of gestational diabetes mellitus have been documented in native populations, few studies have examined rates of the disease among native Indians in Canada. The authors conducted a study to estimate the prevalence of gestational diabetes among Swampy Cree women, to identify factors predictive of the occurrence of gestational diabetes, and to identify delivery and infant outcomes related to the presence of the disease. METHODS: Information on Swampy Cree women who gave birth at Weeneebayko Hospital, Moose Factory, James Bay, Ont., between 1987 and 1995 was obtained from medical charts. Patients with and without gestational diabetes were compared. Logistic regression analysis was used to identify independent predictors of gestational diabetes. Delivery and infant outcomes that occurred secondary to gestational diabetes were also identified by means of logistic regression. RESULTS: A total of 1401 deliveries occurred at Weeneebayko Hospital over the study period, of which 1298 were included in the study. Gestational diabetes was diagnosed in 110 (8.5% [95% confidence interval (CI) 6.9%-9.9%]) of the 1298 pregnancies. Factors predictive of gestational diabetes were age 35 years or more (relative risk [RR] 4.1, 95% CI 1.5-11.7), a history of gestational diabetes in a previous pregnancy (RR 6.4, 95% CI 3.5-11.7), diastolic blood pressure of 80 mm Hg or higher at the first prenatal visit (RR 1.7, 95% CI 1.1-2.8), weight greater than 80 kg at the first prenatal visit (RR 4.9, 95% CI 1.8-12.9) and having a first-degree relative with diabetes (RR 3.0, 95% CI 1.4-6.1). The only delivery outcome independently associated with the presence of gestational diabetes was an increased likelihood of needing assisted delivery (forceps or vacuum extraction) (RR 2.8, 95% CI 1.1-7.0). Shoulder dystocia was indirectly associated with gestational diabetes owing to increased infant birth weight. Infant outcomes associated with the presence of gestational diabetes were birth weight greater than 4500 g (RR 2.4, 95% CI 1.4-3.8), hyperbilirubinemia (RR 2.9, 95% CI 1.4-6.1), hypoglycemia (RR 7.3, 95% CI 3.7-14.4) and hypocalcemia (RR 8.9, 95% CI 2.3-33.7). INTERPRETATION: Gestational diabetes occurred in a significant minority of Swampy Cree women and was associated with a number of adverse outcomes.     

Evaluation of rubella screening in pregnant women

BACKGROUND: The rationale for rubella vaccination in the general population and for screening for rubella in pregnant women is the prevention of congenital rubella syndrome. The objective of this study was to evaluate the effectiveness of the prenatal rubella screening program in Quebec. METHODS: A historical cross-sectional study was designed. Sixteen hospitals with obstetric services were randomly selected, 8 from among the 35 "large" hospitals in the province (500 or more live births/year) and 8 from among the 50 "small" hospitals (fewer than 500 live births/year). A total of 2551 women were randomly selected from all mothers of infants born between Apr. 1, 1993, and Mar. 31, 1994, by means of stratified 2-stage sampling. The proportions of women screened and vaccinated were ascertained from information obtained from the hospital chart, the physician's office and the patient. RESULTS: The overall (adjusted) screening rate was 94.0%. The rates were significantly different between large and small hospitals (94.4% v. 89.6%). Five large hospitals and one small hospital had rates above 95.0%. The likelihood of not having been screened was statistically significantly higher for women who had been pregnant previously than for women pregnant for the first time (4.8% v. 1.4%; p < 0.001). Of the 200 women who were seronegative at the time of screening (8.4%), 79 had been vaccinated postpartum, had a positive serological result on subsequent testing or did not require vaccination, and 59 had not been vaccinated postpartum; for 62, subsequent vaccination status was unknown. INTERPRETATION: Continued improvement in screening practices is needed, especially in small hospitals. Because vaccination rates are unacceptably low, it is crucial that steps be taken to address this issue.     

流动人口中早产相关因素分析

目的：总结佛山地区流动性人口孕妇早产的相关因素,以期为流动人口早产的预防和治疗提供依据。方法通过问卷调查方式采集5474例流动人口相关资料孕妇的基本情况,根据一般人口特征、妇产科和疾病相关方面进行分析。并采用多因素回归分析早产的独立危险因素。结果本组发生早产215例,发生率3.93%。年龄<25岁和>35岁、大学及以上学历者孕妇早产发生率较高;孕产次≥2次、人工流产≥2次、胎膜早破和多胞胎的孕妇发生早产的几率明显升高,孕妇合并子宫肌瘤或子宫畸形、阴道炎、瘢痕子宫等疾病时早产的发生几率明显升高,差异有统计学意义（P<0.05）。多因素回归性分析显示,妊娠次数（95%CI：1.45～4.96）,阴道炎（95%CI：1.39～4.22）及胎膜早破（95%CI：2.01～7.69）是流动人口发生早产的独立危险因素（P<0.05）。结论佛山地区流动性人口孕妇早产与妊娠次数、阴道炎和胎膜早破等密切相关,建议产前检查项目中将阴道分泌物检验列为常规,并对有孕期阴道炎者采取积极的预防和治疗措施。     

双胎妊娠早产原因的回顾性分析

目的寻求防治双胎早产发生的方法,降低双胎妊娠早产的发生率。方法回顾分析自2005—2007年在我院分娩的资料完整的双胎妊娠66例,其中早产组36例,足月产组30例,分析早产的原因,分别计算双胎新生儿出生体重的差比值、孕期宫高增长幅度及腹围增长幅度。结果1.双胎妊娠早产组的病因:胎膜早破11例(30.5%);不明原因的早产9例(25%);生殖道感染7例(19.4%);妊娠期高血压疾病4例(11%);前置胎盘2例(5.6%);胎儿畸形2例(5.6%),一胎死胎1例(3%)。2.早产组中胎膜早破和不明原因早产者的两新生儿出生体质量的差比值较足月产组大,差异有显著性。3.早产组中中胎膜早破和不明原因早产者的宫高及腹围增长幅度均比足月产组高,差异有显著性。结论双胎妊娠早产的常见原因有胎膜早破、不明原因早产,其孕期子宫增长过快、宫内两胎儿生长不平衡可能是其诱因;感染也是引起早产的一个较常见诱因;所以,孕前及孕期初检时应积极处理感染灶;孕中期要控制宫高腹围增长速度,监测两胎儿之间体重变化,及早发现双胎早产危险信号,给予积极预防。     

Relationship between serum antisperm antibodies and anticardiolipin antibodies and clinical pregnancy outcome in an in vitro fertilization and embryo transfer program

Objective　To study the influence of maternal immunological factors on clinical pregnancy outcome in an in vitro fertilization and embryo transfer (IVF-ET) program. Methods　One hundred and fifty IVF-ET treatment cycles from November 1995 to November 1996 were studied. The indication for IVF-ET treatment was bilateral blocked tubes. Serum antisperm antibodies and anticardiolipin antibodies were measured using enzyme-linked immunosorbent assay (ELISA). Cleavage rate and successful pregnancy rate in relation to antibody status of infertile women after IVF-ET treatment were assessed. Results　Lower cleavage rate (64.2%±32.1%) was found in 44 cycles of antisperm antibody seropositive women, compared with 84.8%±18.7% in 106 cycles of seronegative women (P&lt;0.05). The clinical pregnancy rate was 31.8% in antisperm antibody-positive cycles and 20.8% in negative cycles (P&gt;0.05). The abortion rates of the two groups were similar (P&gt;0.05). Lower pregnancy rate (9.5%) was found in 21 cycles of serum anticardiolipin antibody-positive group, compared with 26.3% in 129 cycles of seronegative women (P&lt;0.05). Of patients with bio-chemical pregnancy and no pregnancy, 20.0% and 16.2%, respectively, had seropositive anticardiolipin antibody, compared with 5.6% of patients with clinical pregnancy (P&lt;0.05). Conclusion　Serum immunological factors may play a part in clinical pregnancy outcome in IVF-ET.     

Prospective study of human immunodeficiency virus infection and pregnancy outcomes in intravenous drug users

To determine the effects of human immunodeficiency virus (HIV) infection on pregnancy outcomes, we prospectively studied female intravenous drug users in a methadone program in New York City. Of 191 women with HIV status known prior to pregnancy, 17 (24%) of 70 seropositives and 26 (22%) of 121 seronegatives became pregnant during 28 months of follow-up. Including 54 additional women first tested for HIV antibody after becoming pregnant, 125 pregnancies were studied in 97 women (39 seropositive, 58 seronegative). None of the seropositive pregnant women had advanced HIV-related disease at entry, and only one developed symptomatic disease (oral candidiasis) during pregnancy. No differences were observed between groups in the frequency of spontaneous or elective abortion, ectopic pregnancy, preterm delivery, stillbirth, or low-birth-weight births. Among women giving birth to live infants, seropositives were more likely than seronegatives to be hospitalized for bacterial pneumonia during pregnancy and had an increased tendency for breech presentation, although these events were infrequent. There were otherwise no differences between groups in the occurrence of antenatal, intrapartum, or neonatal complications. Results suggest that asymptomatic HIV infection is not associated with a decreased pregnancy rate or an increased risk of adverse pregnancy outcomes in intravenous drug users, and that an acceleration in HIV-disease status during pregnancy is uncommon.