The Impact of Parity on Course of Labor in a Contemporary Population

Abstract: Background: Few studies have examined in depth the labor progression of multiparas to determine if there is any additional impact of being parous beyond the first birth. The objective of this study was to determine the effect of parity on labor progression in contemporary obstetric practice. Methods: Our sample consisted of all low‐risk women who delivered a term, live‐born infant from January 2002 to March 2004 at a single institution in Delaware, United States (n = 5,589). The median duration of labor by each centimeter of cervical dilation was computed for parity = 0 (n = 2,645); parity = 1 (n = 1,839); parity = 2 (n = 750); and parity = 3 + (n = 355). Results: Multiparas had a significantly faster labor progression from 4 to 10 cm (293, 300, and 313 min, respectively, for parity = 1, parity = 2, and parity = 3 +), compared with nulliparas (383 min for parity = 0), as well as a shorter second stage of labor. However, no significant differences were found in duration of the active phase or the second stage of labor among multiparas. Conclusions: Additional childbearing appears to have no effect of on the progression of labor among multiparous subgroups. The difference in duration of the active phase between nulliparas and multiparas is substantially smaller in a contemporary population. (BIRTH 33:1 March 2006)     

Monozygotic twinning associated with day 5 embryo transfer in pregnancies conceived after IVF

BACKGROUND: This study examines the association between day of embryo transfer and monozygotic (MZ) twinning. METHODS: We used a population-based sample of 108,36 IVF/embryo transfer procedures in which the patients oocytes' were freshly fertilized (non-frozen; non-donor) and 39,98 resultant pregnancies from US clinics in 1999 and 2000. Cases were pregnancies for which the number of fetal hearts observed on ultrasound exceeded the number of embryos transferred. These pregnancies were considered to contain at least one set of MZ twins. A total of 226 MZ pregnancies were compared with two control groups: 23,880 singleton pregnancies (one fetal heart) and 15,092 other multiple-gestation pregnancies (> or = 2 fetal hearts but the number of fetal hearts on ultrasound was less than or equal to the number of embryos transferred). RESULTS: Cases of presumed MZ multiple-gestation pregnancies were more likely to have had a day 5 embryo transfer compared with day 3 embryo transfers than singleton pregnancies [adjusted odds ratio (AOR) = 3.92, 95% confidence interval (CI) = 2.97-5.17] or other multiple-gestation pregnancies (AOR = 3.91, 95% CI = 2.96-5.17) conceived with IVF/embryo transfer. CONCLUSIONS: Day 5 embryo transfer may be associated with increased MZ twinning.     

Preterm delivery rates in North Carolina: are they really declining among non-Hispanic African Americans?

The preterm delivery rate in North Carolina is consistently higher than the national average. However, recent reports suggest that singleton preterm delivery rates for non-Hispanic Whites are increasing while those for non-Hispanic African Americans are decreasing. To study this pattern further, the authors examined data on singleton non-Hispanic White and non-Hispanic African-American births in 1989 and 1999 by using North Carolina vital statistics data. They found that the frequency of preterm delivery rose 1.1% (8.5% to 9.6%) among non-Hispanic Whites but declined 1.4% (17.9% to 16.5%) among non-Hispanic African Americans over the same time period. For both subgroups, a bimodal distribution of birth weights was apparent among preterm births at 28-31 weeks of gestation. The second peak with its cluster of normal-weight infants was more prominent among non-Hispanic African Americans in 1989 than in 1999. To reduce the potential for bias due to misclassification of infant gestational age, frequencies of preterm delivery of infants who weighed less than 2,500 g were calculated. Unlike the original analysis, this calculation showed that preterm delivery increased for both subgroups. A number of non-Hispanic African-American births classified as preterm were apparently term births mistakenly assigned short gestational ages. Such misclassification was more frequent in 1989 than in 1999, inflating 1989 preterm delivery rates.     

Comparison of gestational age classifications: date of last menstrual period vs. clinical estimate

PURPOSE: The purpose was to compare the two different measures of gestational age currently used on birth certificates (the duration of pregnancy based on the date of last menstrual period [LMP] and the clinical estimate [CE] as related to health status indicators. We contrasted these measures by race/ethnicity. METHODS: NCHS natality files for 2000-2002 were used, selecting cases of single live birth to U.S. resident mothers with both LMP and CE gestational age information. RESULTS: Approximately 75% of the records had valid LMP and CE values and for approximately one-half of these, the LMP and CE values did not exactly agree. Overall and for each race and ethnic group, the LMP measures resulted in higher proportions of very preterm, preterm, postterm and SGA births. CE value provided preterm rates of 7.9% and for LMP, 9.9%. The odds ratio of preterm birth for African-Americans using the CE measure was 1.78 [95% Cl 1.77-1.79]. The odds ratio using LMP was 1.93 [95% Cl 1.92-1.94]. Whites were the referent population. CONCLUSIONS: Different measures of gestational age result in different overall and race-specific rates of very preterm, preterm, postterm, and SGA births. These findings indicate that substituting or combining these measures may have consequences.     

Comparison of labor progression between induced and noninduced multiparous women

OBJECTIVE: The incidence of labor induction is rising rapidly in the United States. Among multiparas, labor is often followed with traditional labor curves derived from noninduced pregnancies. We sought to determine how labor progression of multiparous women who presented in spontaneous labor differed from those who were electively induced with and from those induced without preinduction cervical ripening. METHODS: We analyzed data on all low-risk multiparous women with an elective induction or spontaneous onset of labor between 37(+0) and 40(+6) weeks of gestation from January 2002 to March 2004 at a single institution. The median duration of labor by each centimeter of cervical dilatation and the risk of cesarean delivery were computed for 61 women with preinduction cervical ripening and oxytocin induction, 735 women with oxytocin induction, and 1,885 women with a spontaneous onset of labor. An intracervical Foley catheter was used to ripen the cervix. RESULTS: Those women who experienced electively induced labor without cervical ripening had a shorter active phase of labor than did those admitted in spontaneous labor (99 minutes in induced labor versus 161 minutes in spontaneous labor, P < .001). However, the cesarean delivery rate was elevated in the induction group (3.9% versus 2.3%, P < .05). Women who underwent preinduction cervical ripening also had a shorter active phase than those admitted in spontaneous labor (109 minutes versus 161 minutes, P = .01). CONCLUSION: The pattern of labor progression differs for women with an electively induced labor without cervical ripening compared with those who present with spontaneous onset of labor.     

Family-Planning Practices Among Women With Diabetes and Overweight and Obese Women in the 2002 National Survey for Family Growth

OBJECTIVE

To examine contraceptive practices among diabetic women and obese women.

RESEARCH DESIGN AND METHODS

We analyzed the responses of 5,955 participants aged 20–44 years in the 2002 National Survey for Family Growth. Diabetes, BMI, desire for pregnancy, history of infertility treatment, sexual activity, parity, and demographic variables (age, race/ethnicity, education, marital status, income, insurance, and smoking history) were obtained by self-report. Lack of contraception was defined as absence of hormonal-, barrier-, or sterilization-based methods. Associations among contraception, diabetes, and BMI category were assessed in multivariable logistic regression models in nonsterile, sexually active women.

RESULTS

In unadjusted comparisons among sexually active women who were not sterilized, women with diabetes were more likely to lack contraception than women without diabetes (odds ratio [OR] 2.61 [95% CI 1.22–5.58]). Women with BMI ≥35 kg/m² were more likely to lack contraception than women with BMI <25 kg/m²(1.63 [1.16–2.28]), but associations between contraception use and lesser degrees of overweight and obesity were not significant. In multivariable models, women who were older (aged ≥30 vs. 20–29 years), were of non-Hispanic black race, were cohabitating, had a history of infertility treatment, and desired or were ambivalent about pregnancy were significantly more likely to lack contraception. The associations among diabetes, BMI, and contraception were no longer significant after these adjustments.

CONCLUSIONS

Older women with diabetes and obesity who desire pregnancy, regardless of pregnancy intention, should be targeted for preconceptive management.Diabetes and obesity increasingly affect women of reproductive age in the U.S. (1,2). Data from the National Health and Nutrition Examination Survey show that the prevalence of physician-diagnosed diabetes in women aged ≥20 years was 7.1% from 2001 to 2004 (3). Moreover, in 2003–2004, one in three women aged ≥20 years was identified as obese (BMI ≥30 kg/m²) (4). Women with diabetes and those who are obese are at increased risk for pregnancy complications, including those fromsurgical delivery, and their offspring areat riskfor congenital anomalies (5,6). Women with diabetes can improve pregnancy outcomes by delaying pregnancy until optimal glucose levels are reached (7). Obese women are also at risk for gestational diabetes mellitus and future onset of diabetes (8,9). Effective family planning, used in conjunction with glucose management for women with diabetes, as well as weight loss and diabetes screening before pregnancy, may reduce the risk to the mother and fetus associated with diabetes and obesity. In addition, family planning will reduce the risk of mistimed pregnancies (10).Between one-half and two-thirds of women with diabetes have experienced unplanned pregnancies (11–14). However, Chuang et al. (15) found that among sexually active women with diabetes, only a quarter reported no contraceptive use. Similarly, reports of contraceptive practices of obese women vary. While Chuang et al. (15) found that one-fifth of potentially fertile obese women reported no contraceptive use, other reports (16) have found much lower rates of contraception among obese women.It is also not clear to what extent diabetes or obesity are independent riskfactors for contraception nonuse. The objective of this study was to examine contraceptive nonuse and its associations with diabetes and categories of BMI using data from the 2002 National Survey for Family Growth (NSFG). We hypothesized that women with diabetes wouldreport less contraceptive use than nondiabetic women and that this difference would persist after adjustment for demographic factors and potential confounders, such as desire for pregnancy, history of infertility treatment, and obesity. We also hypothesized that overweight and obese women would report less frequent contraceptive use than healthy-weight women after adjustment for potential confounders.     

Experimentelles zur Pathologie und Therapie der cerebralen Neurasthenie

Ohne Zusammenfassung     

Visualization of time-dependent inactivation of human tumor cathepsin B isozymes by a peptidyl fluoromethyl ketone using a fluorescent print technique

A peptidyl fluoromethyl ketone (Z-Phe-Ala CH2F) was found to be an effective compound in a time dependent inactivation of cathepsin B isozymes from a number of tissues including human tumors. The effect was visualized by employing an activity-specific fluorescent print technique preceded by isoelectric focusing. The technique could yield additional information of selective inhibition of isozymes as observed with rat pancreas. The fluoromethyl ketone is 30-fold more potent than the known inhibitor of cathepsin B, Z-Phe-AlaCHN2 in parallel evaluation. Furthermore, the fluoromethyl ketone may have in vivo potential in the inhibition of cathepsin B, in view of the results of toxicological studies. The findings demonstrate that the application of enzyme-directed overlay membranes, impregnated with specific substrates, following isoelectric focusing could be very useful in the study of proteases and their involvement in the oncogenic process.