The effect of the increasing prevalence of maternal obesity on perinatal morbidity.

OBJECTIVE: In this study, we assessed the temporal trends and relative and attributable perinatal risks of maternal obesity over a 20-year period. STUDY DESIGN: We conducted a retrospective cohort study between 1980 and 1999 by using a computerized perinatal database of all women who received prenatal care and delivered their infants within a regional health care system. The main outcome measures were as follows: (1) annual mean body weight and the percentage of women classified as obese at the first prenatal visit (primary definition > or = 200 lb; secondary definitions > or = 250 lb, > or = 300 lb, body mass index > 29 kg/m(2)); and (2) relative and attributable risks of obesity for selected maternal and perinatal morbidities in successive 5-year periods. RESULTS: From 1980 to 1999, the mean maternal weight of women at the first prenatal visit increased 20% (144-172 lb), as did the percentage of women > or = 200 lb (7.3-24.4), the percentage > or = 250 lb (1.9-10.7), the percentage > or = 300 lb (0.5-4.9), and the percentage with a body mass index > 29 kg/m(2) (16.3-36.4), P < .01 for all. Controlling for maternal age, race, and smoking status, obese women were at increased risk at each period for cesarean delivery (range of adjusted relative risk, 1.5-1.8), gestational diabetes (range, 1.8-2.9), and large (> 90th percentile) for gestational age infants (range, 1.8-2.2). From the earliest 5-year period (1980-1984) to the most recent (1995-1999), the percentage of obesity-attributable cesarean deliveries more than tripled from 3.9 to 11.6. Similar percentage increases were observed for the obesity-attributable risks for gestational diabetes (12.8-29.6) and large for gestational age infants (6.5-19.1). Trends for secondary obesity definitions were similar, although the magnitude of the increased attributable risks was smaller. CONCLUSIONS: Efforts to reduce the frequency of certain perinatal morbidities will be constrained unless effective measures to prevent, or limit the risks of, maternal obesity are developed and implemented.

Plasma extracellular superoxide dismutase activity in healthy pregnant women is not influenced by zinc supplementation.

We hypothesized that plasma extracellular superoxide dismutase (EC-SOD) activity reflects the zinc nutriture of healthy pregnant women. Sixty-three women were selected from 580 African-American women who participated in a clinical trial to evaluate the effect of prenatal zinc supplementation on pregnancy outcome. Half of the women received zinc (25 mg/d) and the other half was given a placebo from about 19 wk gestation to delivery. In the trial, a positive effect of zinc supplementation on birthweight was observed, indicating that the population as a whole had suboptimal zinc nutriture. Using plasma samples obtained during the trial, EC-SOD activities were measured and the values were compared with plasma zinc concentrations and plasma alkaline phosphatase activities. Plasma EC-SOD activities in our subjects were lower than previously published values for healthy adults in Korea. Although plasma EC-SOD activity may reflect severe zinc deficiency, it is not a sensitive marker for marginal deficiency status. Plasma EC-SOD activities did not prove to be a better indicator of zinc nutriture of pregnant women than either plasma zinc or plasma alkaline phosphatase activities.

Association of the C677T methylenetetrahydrofolate reductase mutation and elevated homocysteine levels with congenital cardiac malformations.

OBJECTIVE: The aim of this study was determine whether the cytosine-to-thymine mutation at base 677 of the gene for methylenetetrahydrofolate reductase (C677T MTHFR ), which has been associated with neural tube defects, is also associated with congenital cardiac malformations. STUDY DESIGN: Amniotic fluid homocysteine levels were measured and the presence or absence of the C677T MTHFR mutation in amniocytes was determined in stored amniotic fluid obtained from 26 pregnancies complicated by isolated (presumed multifactorial) fetal cardiac defects and from 116 normal pregnancies. RESULTS: The pregnancies affected by fetal cardiac defects had higher amniotic fluid homocysteine levels (1.7 +/- 1.7 vs 1.0 +/- 0.7 micromol/L; P =.07) and included more samples with homocysteine levels >90th percentile (27% vs 9%; P =.02) and more cases with the C677T MTHFR mutation (35% vs 13%; P =.01). Fifty percent of cases had either a high homocysteine level or the C677T MTHFR mutation (50% vs 20%; P =.003) and 12% had both (12% vs 0%; P =.0006). CONCLUSION: Fifty percent of these isolated congenital cardiac defects were associated with either the C677T MTHFR mutation or elevated amniotic fluid homocysteine levels, or both. This finding adds to what is already known about the multiple and complex biochemical and developmental functions of the homocysteine pathway.

Umbilical cord serum levels of thromboxane B2 in term infants of women who participated in a placebo-controlled trial of low-dose aspirin.

OBJECTIVE: Our aim was to quantify thromboxane B2 (TXB2) in umbilical cord serum of term infants of nulliparous, low-risk women who were randomly assigned to either placebo or low-dose (60 mg) aspirin (ASA) on a daily basis from 24 weeks' gestation through delivery as part of a randomized clinical trial for prevention of preeclampsia. METHODS: Umbilical cord sera from 230 singleton, term infants whose mothers were involved in our low-dose ASA trial were assayed for TXB2, the stable metabolite of thromboxane A2, without knowledge of treatment or outcome data. The data were related to assigned treatment group, longitudinal pattern of maternal serum TXB2 levels, and other maternal and newborn characteristics. The data also were analyzed according to whether or not maternal serum levels of TXB2 at 29-31, 34-36, and delivery were reduced > or =50% compared to values prior to initiation of the trial. RESULTS: Umbilical cord TXB2 levels (ng/ml, mean +/- SE) were significantly lower at term in the ASA group (36.1 +/- 3.3, n = 111) than in the placebo group (56.6 +/- 5.7, n = 119; P = 0.002). Umbilical cord TXB2 levels were correlated to those in maternal serum at delivery in the ASA group (r = 0.3441; P = 0.0005) but not in the placebo group (r = 0.0626; P = 0.53). Regardless of assigned treatment group, infants whose mothers had a > or =50% longitudinal reduction in serum TXB2 had lower umbilical cord TXB2 levels (39.2 +/- 3.6, n = 114) than infants whose mothers had <50% reductions in TXB2 (54.6 +/- 5.9, n = 116; P = 0.027). Birthweights of these infants correlated inversely (r = 0.1678, P = 0.017) with maternal serum TXB2 at delivery but not to umbilical cord TXB2 levels; the best correlation between birthweight and maternal serum TXB2 was noted in pregnancies assigned to receive placebo (r = -0.2558, P = 0.009). CONCLUSIONS: Umbilical cord serum levels of TXB2 1) are reduced in instances of long-term maternal ingestion of ASA, 2) correlate well with maternal serum levels of TXB2 at delivery when there is evidence for consistent maternal use of ASA, but 3) do not correlate with maternal serum TXB2 levels when there is no evidence for frequent maternal ingestion of cyclooxygenase inhibitors. These data suggest that the capacity for platelet production of TXA2 in fetal and maternal compartments are regulated independently. Finally, there is an inverse relationship between maternal serum TXB2 levels at delivery and birthweight of newborn infants that is most evident among the pregnancies assigned to placebo and also among pregnancies in which there was little evidence to suggest a pattern of cyclooxygenase inhibitor use during pregnancy.

Second-trimester plasma homocysteine levels and pregnancy-induced hypertension, preeclampsia, and intrauterine growth restriction.

OBJECTIVE: The purpose of this study was to determine whether second-trimester plasma homocysteine levels are elevated among women whose pregnancies are subsequently complicated by pregnancy-induced hypertension, preeclampsia, or intrauterine growth restriction. STUDY DESIGN: Women with normal but relatively low plasma zinc levels were randomly assigned to receive zinc supplementation or placebo from 19 weeks' gestation until delivery. Plasma homocysteine concentration and plasma and erythrocyte folate levels were determined for all available stored samples (zinc group, 231/294; placebo group, 206/286) at 26 and 37 weeks' gestation. Among all women with available samples, pregnancy-induced hypertension (n = 12) or preeclampsia (n = 4) developed in 16 women, and 22 pregnancies were complicated by intrauterine growth restriction. RESULTS: Mean homocysteine levels in women with pregnancy-induced hypertension and preeclampsia were similar to those of control subjects at 26 weeks' gestation but were significantly higher at 37 weeks' gestation. Homocysteine levels were similar between women with pregnancies complicated by intrauterine growth restriction and control subjects at both time points. CONCLUSION: Second-trimester plasma homocysteine concentrations do not predict the subsequent development of pregnancy-induced hypertension, preeclampsia, and intrauterine growth restriction.

Increased risk of preterm delivery with elevated maternal alpha-fetoprotein and plasma zinc levels in African-American women.

BACKGROUND: This study evaluated the relationship of maternal serum alpha-fetoprotein (MSAFP) and plasma zinc levels (PZn) to pregnancy outcome. METHODS: The subjects for this investigation consisted of 917 African-American women, who on registration for prenatal care between 7-22 weeks gestational age (GA), had PZn levels determined and also had MSAFP recorded in their charts. RESULTS: MSAFP levels greater than the 90th percentile significantly increased the risk of PTD (adjusted odds ratio or AOR=2.5, 95% C.I.=1.5-4.2) but not of IUGR. There was no significant relationship between maternal PZn level and PTD or IUGR. When subjects were stratified by MSAFP levels, in women with MSAFP greater than the 90th percentile, the AOR for PTD was 4.0 (95% C.I.=1.2-13.5) for women with PZn levels greater than the median vs. those with PZn equal to or less than the median. In women with MSAFP equal to or less than the 90th percentile, there was no such difference. Multiple regression analyses, using GA at birth as the dependent variable, indicated an interaction between MSAFP and PZn levels. CONCLUSION: In this population, the adverse pregnancy outcome associated with elevated MSAFP was seen only in women with PZn levels greater than the median. The reason for this association is not currently apparent.

Second-trimester cervical ultrasound: associations with increased risk for recurrent early spontaneous delivery.

OBJECTIVE: To determine whether short cervical length or internal os funneling before 20 weeks' gestation predicts early preterm birth or pregnancy loss in women with at least one prior spontaneous early preterm birth. METHODS: Transvaginal cervical ultrasound examinations were done every 2 weeks on 69 women with singleton gestations and histories of at least one prior spontaneous birth between 16 and 30 weeks' gestation. The results of those examinations were correlated with gestational age at delivery. RESULTS: Among 53 women who had ultrasound examinations before 20 weeks' gestation, those with cervical lengths at or below the tenth percentile for the study population (22 mm, n = 4) or funneling of the internal os (n = 5) were more likely than women without those factors to have spontaneous preterm births within 2 weeks (33% versus 0%, P = .01) or 4 weeks from the ultrasound examination (67% versus 0%, P < .001) or before 35 weeks' gestation (100% versus 19%, P < .001). Short cervical length or funneling between 20-24 and 25-29 weeks was also associated with increased risk of spontaneous preterm birth before 35 weeks' gestation (P < or = .05 and P = .002, respectively) but not with increased risk of spontaneous preterm birth within 2 or 4 weeks of ultrasound examination. CONCLUSION: Women with prior early spontaneous preterm births who have short cervical lengths or funneling of the internal cervical os before 20 weeks' gestation are at increased risk of subsequent spontaneous preterm birth.

Maternal plasma zinc concentrations and pregnancy outcome.

BACKGROUND: There is no consensus in the literature as to whether maternal zinc nutriture is associated with pregnancy outcome or fetal growth. OBJECTIVE: We evaluated the associations between plasma zinc concentrations during pregnancy and various measures of pregnancy outcome and neonatal conditions at birth. DESIGN: We measured zinc concentrations in plasma samples obtained at a mean of 16 wk of gestation (range: 6-34 wk) from 3448 women who were screened for a trial designed to evaluate the effect of zinc supplementation on fetal growth. Subjects were from low socioeconomic backgrounds and attended a public health clinic for their prenatal care. Plasma zinc concentrations were compared with pregnancy outcome, including complications during pregnancy and delivery, and anthropometric measures and Apgar scores of neonates. RESULTS: Plasma zinc concentrations declined as gestation progressed. After plasma zinc concentrations were adjusted for gestational age, they were not significantly associated with any measure of pregnancy outcome or neonatal condition. CONCLUSION: We conclude that plasma zinc concentrations during the late first trimester to the early third trimester do not predict pregnancy outcomes in women of a low socioeconomic background.

Effects of maternal infections on fetal adrenal steroid production.

We sought to determine the effect of maternal infections on the fetal hypothalamic-pituitary-adrenal axis. Umbilical cord blood was collected at vaginal delivery after labor (24-44 wk. gestation) from 361 infants of women having normal pregnancy ( apart from preterm delivery in some) and 110 infants of women diagnosed with infections: 86% of these women had amnionitis. Infants exposed to antenatal corticosteroids, being growth retarded, or having developmental abnormalities that would be expected to alter function of the hypothalamic-pituitary unit were excluded. Umbilical cord serum was assayed for dehydroepiandrosterone sulfate (DS) and for cortisol. The data were analyzed by use of SAS. The gestational age of the infants of normal women (35.8+/-0.2 wk., Mean +/- SE) was greater than that of the infants of women having infections (34.3+/-0.4 wk., P = 0.003). Umbilical cord serum levels of DS and cortisol rose as a function of gestational age in both groups of infants (P<0.01). Despite being, on average, 1 wk. younger than the normal infants are, the infants of women having infections during pregnancy had higher serum levels of cortisol and DS than did those infants of the normal women. These data are consistent with activation of the fetal hypothalamic-pituitary-adrenal axis in pregnancies complicated by maternal infections. Such a fetal response could be the consequence of transplacental passage of products of the activated maternal immune system.

Hydramnios prediction of adverse perinatal outcome.

OBJECTIVE: To determine whether hydramnios is associated with an increased risk of adverse perinatal outcomes. METHODS: Computerized records of all ultrasound examinations done at the University of Alabama at Birmingham from 1986 to 1996 (n = 40,065) were reviewed to identify 370 women with singleton pregnancies beyond 20 weeks' gestation and hydramnios diagnosed sonographically by amniotic fluid index of 25 cm or more, largest vertical pocket of 8 cm or more, or subjective impression. Controls were all women with singleton gestations with normal amniotic fluid volumes (n = 36,426). Obstetric outcomes were determined by cross-reference to our database. Cases with hydramnios were compared with controls for perinatal death, anomaly rate, fetal growth restriction (FGR), cesarean delivery, fetal aneuploidy, and maternal diabetes. Cases were sorted according to diabetes status, after which perinatal death, anomaly rate, FGR, cesarean delivery, and fetal aneuploidy were compared again. RESULTS: The incidence of hydramnios was 1%. The perinatal mortality rate in all women with hydramnios was 49 per 1000 births, compared with 14 per 1000 births in the control group (P < .001). Women with hydramnios had 25 times more anomalies than controls (8.4% versus 0.3%; P < .001), although the prevalence of fetal aneuploidy was not significantly different (one in 370 versus one in 3643; P = .10). The cesarean rate was three times higher in women with hydramnios compared with controls (47.0% versus 16.4%; P < .001). When hydramnios cases were divided according to diabetes status, all of the increased risk was in nondiabetic women: Perinatal mortality was 60 per 1000 in nondiabetic women versus 0 per 1000 in diabetic women (P = .03); the anomaly rate was 10.4% versus 0%, respectively (P = .005). CONCLUSION: Hydramnios indicated an increased risk of adverse perinatal outcomes, especially if not associated with diabetes. A comprehensive fetal evaluation, a workup to rule out maternal factors, and fetal surveillance are warranted; amniocentesis for fetal karyotype analysis might not be necessary.

Syphilis, gonorrhoea, and drug abuse among pregnant women in Jefferson County, Alabama, US, 1980-94: monitoring trends through systematically collected health services data.

OBJECTIVE: To assess the association between self reported drug abuse and syphilis and gonorrhoea among pregnant women, Jefferson County, Alabama, United States, 1980-94. STUDY DESIGN: We analysed a prenatal care database and assessed the association of self reported drug use with seropositive syphilis and gonorrhoea using prevalence rates, multiple logistic regression models, and the Pearson correlation coefficient (r) for trends. RESULTS: Overall, 5.5% of the women acknowledged drug abuse, 1.4% had seropositive syphilis, and 4.8% had gonorrhoea. In a multivariate analysis, drug abuse was associated with syphilis (odds ratio 2.9, 95% confidence interval 1.6, 5.3) but not with gonorrhoea. Trends in the annual prevalence of drug abuse closely paralleled trends in the annual prevalence of syphilis, including simultaneous peaks in 1992 (drug abuse, 9.1%; syphilis, 3.2%). There was no such parallel trend between drug abuse and gonorrhoea. Annual prevalence of drug abuse correlated with the prevalence of syphilis (r = 0.89, p = 0.001) more than with the prevalence of gonorrhoea (r = 0.45, p = 0.201). CONCLUSION: Among pregnant women, an increase in drug abuse was closely associated with an epidemic of syphilis, but not of gonorrhoea. Systematically collected prenatal care data can usefully supplement surveillance of diseases and behavioural risk factors associated with them.

72-hour discharge after cesarean delivery: results in a selected Medicaid population.

The purpose of this study was to determine the safety and cost savings of discharging low income patients at 72 hours following cesarean delivery. Predetermined criteria were used to allow discharge. Selection criteria were no medical problems, an afebrile postoperative course, documented bowel function, to have tolerated at least one regular meal, and to have reached 72 hours postdelivery by 6 o'clock PM at discharge. Each patient returned to clinic 2-3 days postdischarge for staple removal. Physicians also discharged some low income patients home at 72 hours even though strict eligibility criteria were not met. Maternal outcome and financial data were compared between patients discharged after meeting eligibility criteria versus those who did not. Of 1,299 cesareans performed from July 1, 1993-July 31, 1995, 906 (70%) were performed in low income patients and 399 (44%) of these women were discharged at 72 hours. Twenty-seven women were lost to follow-up and 286 (77%; Group A) met the eligibility criteria for 72-hour discharge. Eighty-six women (23%; Group B) who did not meet criteria were also discharged at 72 hours. When maternal outcome data from the two groups were compared, Group B patients (did not meet criteria) were more likely to have been readmitted at < or = 30 days (7 of 86; 8% vs. 8 of 286; 3%; P = 0.05) and had longer hospital stays (27 days vs. 22 days) than Group A patients (met criteria). Net cost savings in 2 years was $448 per discharge for Group A, but only $333 per discharge for Group B. In our selective 72-hour discharge program, failure to abide by predetermined guidelines established to select only low risk, afebrile patients for 72-hour discharge resulted in more hospital readmissions, and longer stays and thus was not as cost effective.

Elevated second-trimester amniotic fluid interleukin-6 levels predict preterm delivery.

OBJECTIVE: Our purpose was to determine whether early second-trimester amniotic fluid interleukin-6 levels predict delivery before 34 weeks' gestation. STUDY DESIGN: We used stored second-trimester amniotic fluid samples obtained from women undergoing genetic amniocentesis from 1988 to 1996. Interleukin-6 levels were measured by enzyme-linked immunosorbent assay in samples from every case known to result in delivery from 20 to 34 weeks' gestation (n = 290), and 290 matched controls delivering at > or =37 weeks. Fetal aneuploidies, anomalies, and all cases delivering within 30 days of the amniocentesis (which were thought to be possibly procedure related) were excluded. RESULTS: Interleukin-6 levels were higher in cases than controls (1.9 +/- 5.2 vs 1.0 +/- 2.4 ng/ml, p = 0.004). Cases were grouped according to whether the preterm delivery was indicated or spontaneous: The mean interleukin-6 levels were significantly higher than controls in the spontaneous group (1.6 +/- 3.2 vs 0.8 +/- 1.2 ng/ml, p = 0.01) but not in the indicated group (1.4 +/- 4.0 vs 0.8 +/- 1.2 ng/ml, p = 0.12). In all samples the interleukin-6 level was negatively correlated with the gestational age at delivery (R = -0.11633, p = 0.007). CONCLUSION: Elevated early second-trimester amniotic fluid interleukin-6 levels are associated with preterm delivery, confirming that in some women this indicator of very early intrauterine inflammation predicts birth before 34 weeks' gestation.

Significance of a false-positive trisomy 18 multiple-marker screening test.

OBJECTIVE: To determine if a false-positive trisomy 18 multiple-marker screening test (all three analytes low: maternal serum alpha-fetoprotein [AFP] at most 0.75 multiples of the median [MoM], unconjugated estriol at most 0.60 MoM, and hCG at most 0.55 MoM) indicates increased risk for obstetric complications or is related to maternal weight. METHODS: We accessed our genetic database to obtain multiple-marker screening test results, fetal karyotypes, and pregnancy outcomes from all patients with a normal multiple-marker screening test (n = 3900) and from all patients with a positive trisomy 18 screening test (n = 103) seen in the prenatal diagnosis clinic from 1992 to 1996. During this period, only maternal serum AFP was adjusted for maternal weight. RESULTS: A positive trisomy 18 screen identified five of 12 trisomy 18 fetuses. Women with a false-positive trisomy 18 screen were heavier (175.6 +/- 43.8 lb versus 159.9 +/- 37.9 lb, P < .001) and younger (29.7 +/- 6.5 years versus 32.3 +/- 6.5 years, P < .001) than women with a normal multiple-marker screening test, but were not at increased risk for pregnancy complications. Weight-adjusting all three analytes reduced the false-positive trisomy 18 screen rate by 42% (from 1.9% to 1.1%) but did not change the trisomy 18 detection rate. CONCLUSION: A false-positive trisomy 18 screening test does not indicate increased risk to develop pregnancy complications and may be related to inadequate correction for increased maternal weight.

Plasma and erythrocyte zinc concentrations and their relationship to dietary zinc intake and zinc supplementation during pregnancy in low-income African-American women.

OBJECTIVE: To evaluate the effects of usual dietary intake of zinc and of zinc supplementation during pregnancy on plasma and erythrocyte zinc concentrations. DESIGN: A randomized, double-blind, placebo-controlled trial. SUBJECTS: Low-income African-American women (n = 580) assigned randomly to groups at 19 weeks of gestation. INTERVENTION: A daily dose of zinc (25 mg) or a placebo until delivery. MAIN OUTCOME MEASURES: Plasma, erythrocyte, and dietary zinc levels. STATISTICAL ANALYSES: Multiple regression and repeated measures analysis of variance. RESULTS: In both the placebo and the supplemented groups, when all subjects were grouped by usual dietary zinc intake above or below the median (12 mg/day), results were the same: Women with high dietary zinc intake had higher erythrocyte zinc levels at the time of randomization and at all subsequent measurements during pregnancy than those who had low dietary zinc intake (P < or = .06; difference not significant for zinc-supplemented group); no difference was observed for plasma zinc levels. On the other hand, when the subjects were stratified at the median by total daily zinc intake (usual dietary zinc + 25 mg zinc supplement) during pregnancy, a significant difference in plasma zinc levels (P < .005) was found between women with high total zinc intake (mean = 38 mg/day) and low total intake (mean = 13 mg/day) at 26, 32, and 38 weeks of gestation; however, no such differences were found in erythrocyte zinc levels. APPLICATIONS: These results should help dietitians and other health professionals better understand the expected changes in plasma and erythrocyte zinc levels during pregnancy, and the relationship between dietary and supplemental zinc and zinc nutriture.

Pregnancy outcomes following false-positive multiple marker screening tests.

Pregnancy outcomes in women with a false-positive midtrimester multiple marker screening test (MMST) were reviewed. A genetic database was used to identify all women > or = age 30 who had a MMST at 15-20 weeks of gestation, a targeted ultrasound, and amniocentesis, and complete pregnancy outcome data. All patients with an abnormal fetal ultrasound (US) or karyotype were excluded. The incidence of adverse outcomes (defined as fetal death, preterm delivery, or a birth weight less than the 10th percentile for gestational age), in those women with a positive MMST (risk of Down's syndrome > or = 1:190) was compared to the incidence of adverse outcomes in control women with negative MMST. Chi-square analysis and Fisher's exact tests were used for comparisons as appropriate. Complete data was available from 1135 women. Seventy-seven percent were over age 35. Two hundred and forty-six women (22%) had a positive multiple marker test. No significant differences in outcomes were discovered after comparisons to controls: fetal death 1 of 246 (0.4%) versus 12 of 889 (1.3%), p = 0.32; preterm delivery 32 of 246 (13.0%) versus 147 of 889 (16.5%), p = 0.17; birth weight less than the 10th percentile, 9 of 246 (3.7%) versus 30 of 889 (3.4%), p = 0.83. Our data suggest that women > or = age 30 with a false-positive MMST and a normal midtrimester obstetrical sonogram are not at an increased risk for adverse pregnancy outcomes in later gestation.

Plasma alkaline phosphatase and pregnancy outcome.

The objective was to determine the relationship between plasma alkaline phosphatase (AP) activity and birthweight (BWT) and preterm delivery (PTD). Five hundred eighty African-American women had plasma AP activities measured at various gestational ages (GA) with the results compared to a number of pregnancy outcomes. Plasma AP activity rose linearly during pregnancy from a mean of 39 U/L at 19 weeks to 130 U/L at delivery. In individual women, AP activities were consistently high or low as confirmed by correlation coefficients in adjacent time periods ranging from 0.63 to 0.87. AP at 19 weeks was not significantly associated with any outcome measure. However, at 26 weeks, AP in the highest quartile was associated with a 15.0% incidence of PTD < 37 weeks compared to 6.8% in the lower three quartiles (P = .004). For PTD < or = 32 weeks, the difference of PTD was 6.8 vs. 1.6% (P < .003). When women in the highest quartile of increase in AP from 19 to 26 weeks were compared to those in the lower quartiles, the rate of PTD < 37 weeks was 15.2 vs. 6.4% (P = .002), and the rate of PTD < or = 32 weeks was 6.1 vs. 1.7%, (P = .01). The mean BWT for the highest vs. the lower three quartiles in rate of increase was 3,058 vs. 3,288 g (P = .0005) and the mean GA was 38.1 vs. 39.2 weeks (P = .0001). Regression analyses adjusting for multiple confounders confirmed the association between high AP at 26 weeks and PTD < 37 weeks [OR (95% C.I.), 2.4 (1.2-4.8)] and PTD < or = 32 weeks [OR (95% C.I.), 3.7 (1.2-11.7)]. Similar results were found among women with a large increase in AP between 19 and 26 weeks. From these results we conclude that high or increasing AP activity at 26 weeks, but not 19 weeks, was significantly associated with subsequent PTD and a lower BWT.

The relationship between maternal characteristics and fetal and neonatal anthropometric measurements in women delivering at term: a summary.

BACKGROUND: We wanted to determine the relationship between a number of maternal characteristics and various fetal and neonatal anthropometric measurements determined by ultrasound and at birth. METHODS: A total of 1205 term singleton maternal-infant pairs were studied. Various ultrasound measurements obtained at 18, 24, 30 and 36 weeks' gestation and neonatal anthropometric measurements obtained at birth were studied in relationship to various maternal characteristics using univariate and multivariate techniques. RESULTS: Black race, female sex, cigarette smoking, drug use, having a previous low birthweight infant, maternal hypertension and being short or thin or failing to gain weight each resulted in a birthweight decrease of 100 to 300 g. The effect of each of these characteristics on each ultrasound measurement, the timing of the effect, and its ultimate effect on neonatal anthropometric measurements are described. CONCLUSION: The data presented in this paper provide a more complete understanding of the relationship between maternal characteristics, infant sex, and various fetal ultrasound and neonatal measurements.

Pregnancy outcome and intelligence at age five years.

OBJECTIVE: Our purpose was to determine the influence of being small for gestational age at term and being preterm < 34 weeks on cognitive functioning at age 5 years. STUDY DESIGN: Five hundred forty-six children of black low-income mothers, nearly all at risk for being small for gestational age, followed up prenatally with early ultrasonographic gestational age dating, were classified as either term appropriate for gestational age, term small for gestational age, or preterm at < 34 weeks. At a mean of 5.5 +/- 0.5 years, a Wechsler Preschool and Primary Scale of Intelligence-Revised intelligence quotient test was administered. An intelligence quotient < 70 was used to define mental retardation. Univariate and multivariate analyses adjusted for maternal age, smoking, education and language skills, home environment, and child gender and preschool attendance were performed. RESULTS: Term small-for-gestational-age and preterm infants at < 34 weeks had 4 and 6 point intelligence quotient reductions compared with term appropriate-for-gestational-age infants. In the regression analyses these differences in intelligence quotient remained significant after confounders were adjusted. High maternal receptive language level (8 points), a positive home environment (5 points), and attendance at preschool (5 points) were each significantly associated with an increase in intelligence quotient. CONCLUSION: Both term small-for-gestational-age infants and those born at < 34 weeks had a significantly lower mean intelligence quotient, and small-for-gestational-age infants had an increased risk of mental retardation at age 5 years. Higher maternal language skills, a positive home environment, and attendance at preschool each were associated with an increase in the mean intelligence quotient of 5 to 7 points.

Plasma ferritin and pregnancy outcome.

OBJECTIVE: Plasma ferritin is considered the best measure of total body iron, with low levels diagnostic of iron deficiency. High levels have been associated with inflammation and infection. We determined the relationship between plasma ferritin, birth weight, and preterm delivery. STUDY DESIGN: Plasma ferritin and hematocrit values were measured at 19, 26, and 36 weeks' gestational age and correlated with birth weight and preterm delivery (< or = 32 and < 37 weeks) in 580 indigent black women. RESULTS: Hematocrit levels measured at any gestational age did not correlate significantly with birth weight or preterm delivery. Regardless of the gestational age of sampling, ferritin levels in the lowest quartile did not correlate significantly with subsequent preterm delivery. However, at 26 weeks, compared with the three lower quartiles, ferritin levels in the highest quartile were significantly associated with preterm delivery < or = 32 weeks, 6.5% versus 2.3% (p = 0.02), with preterm delivery < 37 weeks, 14% versus 8% (p = 0.04), and with birth weight < 1500 gm, 6.5% versus 2.0% (p = 0.01). Plasma ferritin levels in the highest quartile at 19, 26, and 36 weeks were associated with birth weight < or = 2500 gm, 14% versus 8% (p = 0.03), 12% versus 7% (p = 0.05), and 10% versus 2% (p = 0.0001), respectively, compared with the lower quartiles. Ferritin levels in the highest quartile were always associated with a lower mean birth weight than were those in the lower three quartiles: 19 weeks, 2999 gm versus 3225 gm, (p = 0.002); 26 weeks, 3065 gm versus 3257 gm, (p = 0.005); and 36 weeks, 3182 gm versus 3323 gm, (p = 0.009). Regression analyses controlling for multiple potential confounders confirmed that at 26 weeks ferritin levels in the highest quartile had an odds ratio and 95% confidence interval for preterm birth < 37 weeks of 2.0 (1.1 to 3.8), preterm delivery < or = 32 weeks of 2.7 (0.99 to 7.6), birth weight < or = 1500 gm of 3.9 (1.2 to 12.2), and birth weight < or = 2500 gm of 2.0 (1.0 to 4.0) compared with the three lower ferritin quartiles. CONCLUSION: High, but not low, plasma ferritin levels, especially at 26 weeks, were strongly associated with subsequent preterm delivery and birth weight.