Altered fetal growth, placental abnormalities, and stillbirth

Background

Worldwide, stillbirth is one of the leading causes of death. Altered fetal growth and placental abnormalities are the strongest and most prevalent known risk factors for stillbirth. The aim of this study was to identify patterns of association between placental abnormalities, fetal growth, and stillbirth.

Methods and findings

Population-based case-control study of all stillbirths and a representative sample of live births in 59 hospitals in 5 geographic areas in the U.S. Fetal growth abnormalities were categorized as small (<10th percentile) and large (>90th percentile) for gestational age at death (stillbirth) or delivery (live birth) using a published algorithm. Placental examination by perinatal pathologists was performed using a standardized protocol. Data were weighted to account for the sampling design. Among 319 singleton stillbirths and 1119 singleton live births at ≥24 weeks at death or delivery respectively, 25 placental findings were investigated. Fifteen findings were significantly associated with stillbirth. Ten of the 15 were also associated with fetal growth abnormalities (single umbilical artery; velamentous insertion; terminal villous immaturity; retroplacental hematoma; parenchymal infarction; intraparenchymal thrombus; avascular villi; placental edema; placental weight; ratio birth weight/placental weight) while 5 of the 15 associated with stillbirth were not associated with fetal growth abnormalities (acute chorioamnionitis of placental membranes; acute chorioamionitis of chorionic plate; chorionic plate vascular degenerative changes; perivillous, intervillous fibrin, fibrinoid deposition; fetal vascular thrombi in the chorionic plate). Five patterns were observed: placental findings associated with (1) stillbirth but not fetal growth abnormalities; (2) fetal growth abnormalities in stillbirths only; (3) fetal growth abnormalities in live births only; (4) fetal growth abnormalities in stillbirths and live births in a similar manner; (5) a different pattern of fetal growth abnormalities in stillbirths and live births.

Conclusions

The patterns of association between placental abnormalities, fetal growth, and stillbirth provide insights into the mechanism of impaired placental function and stillbirth. They also suggest implications for clinical care, especially for placental findings amenable to prenatal diagnosis using ultrasound that may be associated with term stillbirths.

Perinatal outcomes associated with intrahepatic cholestasis of pregnancy. J Matern Fetal Neonatal Med 2017;31:1913-1920. [PMID: 28581354 DOI: 10.1080/14767058.2017.1332036]

OBJECTIVE

The objective of this study is to examine perinatal outcomes associated with cholestasis of pregnancy according to bile acid level and antenatal testing practice.

STUDY DESIGN

Retrospective cohort study of women with symptoms and bile acid testing from 2005 to 2014. Women were stratified by bile acid level: no cholestasis (<10 μmol/L), mild (10-39 μmol/L), moderate (40-99 μmol/L), and severe (≥100 μmol/L). The primary outcome was composite neonatal morbidity (hypoxic ischemic encephalopathy, severe intraventricular hemorrhage, bronchopulmonary dysplasia, necrotizing enterocolitis, or death).

RESULTS

785 women were included; 487 had cholestasis (347 mild, 108 moderate, 32 severe) and 298 did not. After controlling for gestational age (GA), severe cholestasis was associated with the composite neonatal outcome (aRR 5.6, 95% CI 1.3-23.5) and meconium-stained fluid (aRR 4.82, 95%CI 1.6-14.2). Bile acid levels were not correlated with the frequency of testing (p = .50). Women who underwent twice weekly testing were delivered earlier (p = .016) than women tested less frequently, but the difference in GA was ≤4 d. Abnormal testing prompting delivery was uncommon. Among women with cholestasis, there were three stillbirths. One of these women was undergoing antenatal testing, which was normal 1 d prior to the fetal demise.

CONCLUSION

Severe cholestasis is associated with neonatal morbidity which antenatal testing may not predict.

Treatment of Subclinical Hypothyroidism or Hypothyroxinemia in Pregnancy

BACKGROUND

Subclinical thyroid disease during pregnancy may be associated with adverse outcomes, including a lower-than-normal IQ in offspring. It is unknown whether levothyroxine treatment of women who are identified as having subclinical hypothyroidism or hypothyroxinemia during pregnancy improves cognitive function in their children.

METHODS

We screened women with a singleton pregnancy before 20 weeks of gestation for subclinical hypothyroidism, defined as a thyrotropin level of 4.00 mU or more per liter and a normal free thyroxine (T4) level (0.86 to 1.90 ng per deciliter [11 to 24 pmol per liter]), and for hypothyroxinemia, defined as a normal thyrotropin level (0.08 to 3.99 mU per liter) and a low free T4 level (<0.86 ng per deciliter). In separate trials for the two conditions, women were randomly assigned to receive levothyroxine or placebo. Thyroid function was assessed monthly, and the levothyroxine dose was adjusted to attain a normal thyrotropin or free T4 level (depending on the trial), with sham adjustments for placebo. Children underwent annual developmental and behavioral testing for 5 years. The primary outcome was the IQ score at 5 years of age (or at 3 years of age if the 5-year examination was missing) or death at an age of less than 3 years.

RESULTS

A total of 677 women with subclinical hypothyroidism underwent randomization at a mean of 16.7 weeks of gestation, and 526 with hypothyroxinemia at a mean of 17.8 weeks of gestation. In the subclinical hypothyroidism trial, the median IQ score of the children was 97 (95% confidence interval [CI], 94 to 99) in the levothyroxine group and 94 (95% CI, 92 to 96) in the placebo group (P=0.71). In the hypothyroxinemia trial, the median IQ score was 94 (95% CI, 91 to 95) in the levothyroxine group and 91 (95% CI, 89 to 93) in the placebo group (P=0.30). In each trial, IQ scores were missing for 4% of the children. There were no significant between-group differences in either trial in any other neurocognitive or pregnancy outcomes or in the incidence of adverse events, which was low in both groups.

CONCLUSIONS

Treatment for subclinical hypothyroidism or hypothyroxinemia beginning between 8 and 20 weeks of gestation did not result in significantly better cognitive outcomes in children through 5 years of age than no treatment for those conditions. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the National Institute of Neurological Disorders and Stroke; ClinicalTrials.gov number, NCT00388297 .).

Placenta previa and maternal hemorrhagic morbidity

OBJECTIVE

Placenta previa is associated with maternal hemorrhage, but most literature focuses on morbidity in the setting of placenta accreta. We aim to characterize maternal morbidity associated with previa and to define risk factors for hemorrhage.

METHODS

This is a secondary cohort analysis of the NICHD Maternal-Fetal Medicine Units Network Cesarean Section Registry. This analysis included all women undergoing primary Cesarean delivery without placenta accreta. About 496 women with previa were compared with 24,201 women without previa. Primary outcome was composite maternal hemorrhagic morbidity. Non-hemorrhagic morbidities and risk factors for hemorrhage were also evaluated.

RESULTS

Maternal hemorrhagic morbidity was more common in women with previa (19 versus 7%, aRR 2.6, 95% CI 1.9-3.5). Atony requiring uterotonics (aRR 3.1, 95% CI 2.0-4.9), red blood cell transfusion (aRR 3.8, 95% CI 2.5-5.7), and hysterectomy (aRR 5.1, 95% CI 1.5-17.3) were also more common with previa. For women with previa, factors associated with maternal hemorrhage were pre-delivery anemia, thrombocytopenia, diabetes, magnesium use, and general anesthesia.

CONCLUSION

Placenta previa is an independent risk factor for maternal hemorrhagic morbidity. Some risk factors are modifiable, but many are intrinsic to the clinical scenario.

Pregnancies After the Diagnosis of Mild Gestational Diabetes Mellitus and Risk of Cardiometabolic Disorders

OBJECTIVE

To assess the association of subsequent pregnancy with subsequent metabolic syndrome and type II diabetes mellitus after a pregnancy complicated by mild gestational diabetes mellitus (GDM).

METHODS

We conducted a prospective observational follow-up study of women with mild GDM randomized from 2002 to 2007 to usual care or dietary intervention and glucose self-monitoring. Women were evaluated 5-10 years after the parent study. Participants were grouped according to the number of subsequent pregnancies (group A, none [reference]; group B, one; group C, two or greater). Serum triglycerides, glucose tolerance, high-density lipoprotein cholesterol, blood pressure, and waist circumference were assessed. Metabolic syndrome was diagnosed by American Heart Association and National Heart Lung and Blood Institute criteria. Multivariable regression was used to estimate adjusted relative risks (RRs) and 95% confidence intervals (CIs).

RESULTS

Of 905 eligible women from the original trial, 483 agreed to participate, 426 of whom were included in this analysis. Groups A, B, and C consisted of 212, 143, and 71 women, respectively. Of women with subsequent pregnancies, 32% (69/214) had another pregnancy complicated with GDM. No difference between groups was observed for metabolic syndrome (group A, 34%; group B, 33%; group C, 30%). Subsequent pregnancies were associated with diabetes mellitus outside of pregnancy (group A, 5.2%; group B, 10.5%, RR 2.62, 95% CI 1.16-5.91; group C, 11.3%, RR 2.83, 95% CI 1.06-7.59), and if complicated with GDM (no subsequent GDM pregnancy, RR 1.99, 95% CI 0.82-4.84; subsequent GDM pregnancy, RR 3.75, 95% CI 1.60-8.82).

CONCLUSION

In women with prior mild GDM, subsequent pregnancies did not increase the frequency of metabolic syndrome, but subsequent pregnancies with GDM increased the risk of diabetes mellitus outside of pregnancy.

Class III Obese Women's Preferences and Concerns for Cesarean Skin Incision: A Multicenter Survey

Objective This study aims to assess class III obese women's preferences and concerns regarding cesarean delivery (CD) skin incisions. Study Design Through the National Perinatal Research Consortium (NPRC), women with body mass index ≥ 40 kg/m² at the time of enrollment completed an anonymous survey in English or Spanish. We evaluated seven domains of preferences and concerns about the cesarean skin incision. Results We surveyed 546 women at five NPRC sites. Median age (interquartile range) was 29 (25, 35) years; 364 (66%) were parous and 161 (30%) had a prior CD. Women self-identified race/ethnicity as White (31%), non-Hispanic Black (31%), Hispanic (31%), other (6%), and not reported (1%). A total of 542 women (99%) rated both delivering the baby in the best possible condition and decreasing incision opening/infection risk as important. Women were less likely to rate other domains as important (all p < 0.001), including: having least pain possible, n = 521 (95%); decreasing the risk of complications in the next pregnancy, n = 490 (90%); decreasing interference with breastfeeding, n = 474 (87%); decreasing operative time, n = 388 (71%); and having the least visible incision, n = 369 (68%). Conclusion Women with class III obesity prioritize immediate maternal and fetal safety regarding CD skin incision over other concerns including cosmetic outcome.

Relationship Between Excessive Gestational Weight Gain and Neonatal Adiposity in Women With Mild Gestational Diabetes Mellitus

OBJECTIVE

To evaluate the relationships among excessive gestational weight gain, neonatal adiposity, and adverse obstetric outcomes in women with mild gestational diabetes mellitus.

METHODS

This is a secondary analysis of a multicenter randomized clinical trial of women with mild gestational diabetes mellitus. Based on self-reported prepregnancy body weight, gestational weight gain was categorized as excessive if it was greater than 2009 Institute of Medicine guidelines. Maternal outcomes and neonatal anthropomorphic characteristics were compared between women with excessive weight gain and those without excessive weight gain. Multiple linear and logistic regression analyses were performed to adjust for confounding factors.

RESULTS

We studied 841 women who participated in the main trial and had prepregnancy body mass index (BMI) and delivery information available (n=431 treatment group, n=410 no treatment). After adjustment for factors including treatment and prepregnancy BMI, excessive weight gain remained associated with large for gestational age (adjusted odds ratio [OR] 2.94, 95% confidence interval [CI] 1.81-4.93), birth weight greater than 4,000 g (adjusted OR 2.56, 95% CI 1.54-4.40), preeclampsia (adjusted OR 2.96, 95% CI 1.35-7.03), and cesarean delivery for labor arrest (adjusted OR 2.37, 95% CI 1.30-4.44). In addition, excessive weight gain was independently associated with increased total neonatal fat (P<.001) and birth weight (P<.001).

CONCLUSION

In women with both treated and untreated mild gestational diabetes mellitus, excessive gestational weight gain was independently associated with both greater birth weight and adiposity.

Maternal and Neonatal Outcomes With Early Compared With Delayed Pushing Among Nulliparous Women

OBJECTIVE

To describe factors associated with delayed pushing and evaluate the relationship between delayed pushing and perinatal outcomes in nulliparous women with singleton term gestations.

METHODS

This was a secondary analysis of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Assessment of Perinatal Excellence cohort of 115,502 women and their neonates born in 25 U.S. hospitals from 2008 to 2011. Nulliparous women with singleton, cephalic, nonanomalous term births who achieved 10-cm cervical dilation were included. Women in whom pushing was delayed by 60 minutes or greater (delayed group) were compared with those who initiated pushing within 30 minutes (early group). Multivariable regression analyses were used to assess the independent association of delayed pushing with mode of delivery, length of the second stage, and other maternal and perinatal outcomes (significance defined as P<.05).

RESULTS

Of 21,034 women in the primary analysis sample, pushing was delayed in 18.4% (n=3,870). Women who were older, privately insured, or non-Hispanic white as well as those who had induction or augmentation of labor, diabetes, or epidural analgesia were more likely to have delayed pushing. Delayed pushing was more common when the second stage began during daytime hours or in hospitals with dedicated 24-hour obstetric anesthesia, although differences were small. After adjusting for differences in baseline and labor characteristics including center, women in the delayed group had longer mean durations of the second stage (191 compared with 84 minutes, P<.001) and of active pushing (86 compared with 76 minutes, P<.001). Delayed pushing was associated with greater rates of cesarean delivery (11.2% compared with 5.1%; adjusted odds ratio [OR] 1.86, 95% confidence interval [CI] 1.63-2.12), operative vaginal delivery (adjusted OR 1.26, 95% CI 1.14-1.40), postpartum hemorrhage (adjusted OR 1.43, 95% CI 1.05-1.95), and blood transfusion (adjusted OR 1.51, 95% CI 1.04-2.17). Delayed pushing was not associated with increased odds of adverse neonatal outcomes compared with early pushing.

CONCLUSION

In this large birth cohort, delayed pushing was associated with longer second stage duration, increased odds of cesarean delivery, and increased odds of postpartum hemorrhage, but was not associated with neonatal morbidity.

Nonresponse to 17-alpha hydroxyprogesterone caproate for recurrent spontaneous preterm birth prevention: clinical prediction and generation of a risk scoring system

BACKGROUND

Spontaneous preterm birth remains a leading cause of neonatal morbidity and mortality among nonanomalous neonates in the United States. Spontaneous preterm birth tends to recur at similar gestational ages. Intramuscular 17-alpha hydroxyprogesterone caproate reduces the risk of recurrent spontaneous preterm birth. Unfortunately, one-third of high-risk women will have a recurrent spontaneous preterm birth despite 17-alpha hydroxyprogesterone caproate therapy; the reasons for this variability in response are unknown.

OBJECTIVE

We hypothesized that clinical factors among women treated with 17-alpha hydroxyprogesterone caproate who suffer recurrent spontaneous preterm birth at a similar gestational age differ from women who deliver later, and that these associations could be used to generate a clinical scoring system to predict 17-alpha hydroxyprogesterone caproate response.

STUDY DESIGN

Secondary analysis of a prospective, multicenter, randomized controlled trial enrolling women with ≥1 previous singleton spontaneous preterm birth <37 weeks' gestation. Participants received daily omega-3 supplementation or placebo for the prevention of recurrent preterm birth; all were provided 17-alpha hydroxyprogesterone caproate. Women were classified as a 17-alpha hydroxyprogesterone caproate responder or nonresponder by calculating the difference in delivery gestational age between the 17-alpha hydroxyprogesterone caproate-treated pregnancy and her earliest previous spontaneous preterm birth. Responders were women with pregnancy extending ≥3 weeks later compared with the delivery gestational age of their earliest previous preterm birth; nonresponders delivered earlier or within 3 weeks of the gestational age of their earliest previous preterm birth. A risk score for nonresponse to 17-alpha hydroxyprogesterone caproate was generated from regression models via the use of clinical predictors and was validated in an independent population. Data were analyzed with multivariable logistic regression.

RESULTS

A total of 754 women met inclusion criteria; 159 (21%) were nonresponders. Responders delivered later on average (37.7±2.5 weeks) than nonresponders (31.5±5.3 weeks), P<.001. Among responders, 27% had a recurrent spontaneous preterm birth (vs 100% of nonresponders). Demographic characteristics were similar between responders and nonresponders. In a multivariable logistic regression model, independent risk factors for nonresponse to 17-alpha hydroxyprogesterone caproate were each additional week of gestation of the earliest previous preterm birth (odds ratio, 1.23; 95% confidence interval, 1.17-1.30, P<.001), placental abruption or significant vaginal bleeding (odds ratio, 5.60; 95% confidence interval, 2.46-12.71, P<.001), gonorrhea and/or chlamydia in the current pregnancy (odds ratio, 3.59; 95% confidence interval, 1.36-9.48, P=.010), carriage of a male fetus (odds ratio, 1.51; 95% confidence interval, 1.02-2.24, P=.040), and a penultimate preterm birth (odds ratio, 2.10; 95% confidence interval, 1.03-4.25, P=.041). These clinical factors were used to generate a risk score for nonresponse to 17-alpha hydroxyprogesterone caproate as follows: black +1, male fetus +1, penultimate preterm birth +2, gonorrhea/chlamydia +4, placental abruption +5, earliest previous preterm birth was 32-36 weeks +5. A total risk score >6 was 78% sensitive and 60% specific for predicting nonresponse to 17-alpha hydroxyprogesterone caproate (area under the curve=0.69). This scoring system was validated in an independent population of 287 women; in the validation set, a total risk score >6 performed similarly with a 65% sensitivity, 67% specificity and area under the curve of 0.66.

CONCLUSIONS

Several clinical characteristics define women at risk for recurrent preterm birth at a similar gestational age despite 17-alpha hydroxyprogesterone caproate therapy and can be used to generate a clinical risk predictor score. These data should be refined and confirmed in other cohorts, and women at high risk for nonresponse should be targets for novel therapeutic intervention studies.

Factor V Leiden, prothrombin G20210A, and methylene tetrahydrofolate reductase mutations and stillbirth: the Stillbirth Collaborative Research Network

BACKGROUND

An evaluation for heritable thrombophilias is recommended in the evaluation of stillbirth. However, the association between thrombophilias and stillbirth remains uncertain.

OBJECTIVE

We sought to assess the association between maternal and fetal/placental heritable thrombophilias and stillbirth in a population-based, case-control study in a geographically, racially, and ethnically diverse population.

STUDY DESIGN

We conducted secondary analysis of data from the Stillbirth Collaborative Research Network, a population-based case-control study of stillbirth. Testing for factor V Leiden, prothrombin G20210A, methylene tetrahydrofolate reductase C677T and A1298C, and plasminogen activating inhibitor (PAI)-1 4G/5G mutations was done on maternal and fetal (or placental) DNA from singleton pregnancies. Data analyses were weighted for oversampling and other aspects of the design. Odds ratios (OR) were generated from univariate models regressing stillbirth/live birth status on each thrombophilia marker.

RESULTS

Results were available for ≥1 marker in 488 stillbirths and 1342 live birth mothers and 405 stillbirths and 990 live birth fetuses. There was an increased odds of stillbirth for maternal homozygous factor V Leiden mutation (2/488; 0.4% vs 1/1380; 0.0046%; OR, 87.44; 95% confidence interval, 7.88-970.92). However, there were no significant differences in the odds of stillbirth for any other maternal thrombophilia, even after stratified analyses. Fetal 4G/4G PAI-1 (OR, 0.63; 95% confidence interval, 0.43-0.91) was associated with decreased odds of stillbirth. Other fetal thrombophilias were similar among groups.

CONCLUSION

Most maternal and fetal thrombophilias were not associated with stillbirth. Maternal factor V Leiden was weakly associated with stillbirth, and the fetal PAI-1 4G/4G polymorphism was associated with live birth. Our data do not support routine testing for heritable thrombophilias as part of an evaluation for possible causes of stillbirth.

Association of Recorded Estimated Fetal Weight and Cesarean Delivery in Attempted Vaginal Delivery at Term

OBJECTIVE

To evaluate the association between documentation of estimated fetal weight, and its value, with cesarean delivery.

METHODS

This was a secondary analysis of a multicenter observational cohort of 115,502 deliveries from 2008 to 2011. Data were abstracted by trained and certified study personnel. We included women at 37 weeks of gestation or greater attempting vaginal delivery with live, nonanomalous, singleton, vertex fetuses and no history of cesarean delivery. Rates and odds ratios (ORs) were calculated for women with ultrasonography or clinical estimated fetal weight compared with women without documentation of estimated fetal weight. Further subgroup analyses were performed for estimated fetal weight categories (less than 3,500, 3,500-3,999, and 4,000 g or greater) stratified by diabetic status. Multivariable analyses were performed to adjust for important potential confounding variables.

RESULTS

We included 64,030 women. Cesarean delivery rates were 18.5% in the ultrasound estimated fetal weight group, 13.4% in the clinical estimated fetal weight group, and 11.7% in the no documented estimated fetal weight group (P<.001). After adjustment (including for birth weight), the adjusted OR of cesarean delivery was 1.44 (95% confidence interval [CI] 1.31-1.58, P<.001) for women with ultrasound estimated fetal weight and 1.08 for clinical estimated fetal weight (95% CI 1.01-1.15, P=.017) compared with women with no documented estimated fetal weight (referent). The highest estimates of fetal weight conveyed the greatest odds of cesarean delivery. When ultrasound estimated fetal weight was 4,000 g or greater, the adjusted OR was 2.15 (95% CI 1.55-2.98, P<.001) in women without diabetes and 9.00 (95% CI 3.65-22.17, P<.001) in women with diabetes compared to those with estimated fetal weight less than 3,500 g.

CONCLUSION

In this contemporary cohort of women attempting vaginal delivery at term, documentation of estimated fetal weight (obtained clinically or, particularly, by ultrasonography) was associated with increased odds of cesarean delivery. This relationship was strongest at higher fetal weight estimates, even after controlling for the effects of birth weight and other factors associated with increased cesarean delivery risk.

Is Mid-trimester Insulin Resistance Predictive of Subsequent Puerperal Infection? A Secondary Analysis of Randomized Trial Data

Objective The objective of this study was to examine whether there is an association between insulin resistance and subsequent development of puerperal infection by measuring insulin resistance in the mid-trimester using the homeostasis model assessment (HOMA:IR). Methods Secondary analysis of low-risk nulliparas enrolled in a multicenter preeclampsia prevention trial. HOMA:IR was measured on fasting plasma glucose and insulin concentrations among low-risk nulliparas between 22 and 26 weeks' gestation. Median HOMA:IR was compared between women who did and did not develop puerperal infection using Wilcoxon rank sum test. Logistic regression was used to control for potential confounders. Results Of 1,180 women with fasting glucose and insulin available, 121 (10.3%) had a puerperal infection. Median HOMA:IR was higher among those with subsequent puerperal infection (4.3 [interquartile, IQR: 2.2-20.5] vs. 2.6 [IQR: 1.5-6.7], p < 0.0001). After controlling for potentially confounding variables HOMA:IR was only marginally associated with an increased risk of development of puerperal infection, adjusted odds ratio: 1.01 (95% confidence interval: 1.00-1.02; p = 0.04) per unit increase. Elevated HOMA:IR performed poorly as a predictor of puerperal infection, with a positive predictive value of 15% and a negative predictive value of 92%. Conclusion Though associated with an increased risk of puerperal infection, insulin resistance, measured by HOMA:IR, is not a clinically useful predictor of puerperal infection.

Intrapartum Cervical Laceration and Subsequent Pregnancy Outcomes

OBJECTIVE

The objective of this study was to describe pregnancy outcomes, including cervical insufficiency and preterm birth, in the subsequent pregnancy following an intrapartum cervical laceration.

STUDY DESIGN

Retrospective cohort of women with their first two consecutive singleton pregnancies carried to ≥ 20(0/7) weeks' gestation within a tertiary health care system from 2002 to 2012. Cervical laceration cases were identified by ICD9 codes and included if suture repair was required.

RESULTS

In this study, 55 women were confirmed to have a cervical laceration in the first delivery; 43 lacerations after vaginal delivery (VD) and 12 after cesarean delivery (CD). The median gestational age of the first delivery was 40(0/7) weeks and the median birth weight 3,545 g; these did not differ between VD and CD. In the second pregnancy, 2 of 55 women (4.6%) had a prophylactic cerclage placed; 1 carried to term and the other delivered at 35(6/7) weeks. In total, four women (9.3%) delivered the second pregnancy < 37 weeks: three had a prior term VD and one had a prior 34 weeks VD. There was only one case of recurrent cervical laceration, occurring in the setting of vaginal deliveries.

CONCLUSION

Obstetric cervical lacerations are uncommon. Complications in the following pregnancy were low, despite lack of additional prophylactic cerclage use.

Influenza in Infants Born to Women Vaccinated During Pregnancy

BACKGROUND

Infants <6 months old with influenza are at risk for adverse outcomes. Our objective was to compare influenza outcomes in infants <6 months old born to women who did and did not report influenza vaccine during pregnancy.

METHODS

The study included all women who delivered from 12/2005 to 3/2014 at Intermountain facilities and their infants. Influenza outcomes included infant influenza-like illness (ILI), laboratory-confirmed influenza, and influenza hospitalizations.

RESULTS

The cohort included 245 386 women and 249 387 infants. Overall, 23 383 (10%) pregnant women reported influenza immunization. This number increased from 2.2% before the H1N1 pandemic to 21% postpandemic (P < .001). A total of 866 infants <6 months old had ≥1 ILI encounter: 32 (1.34/1000) infants born to women reporting immunization and 834 (3.70/1000) born to women who did not report immunization (relative risk [RR] 0.36; 95% confidence interval [CI], 0.26-0.52; P < .001). A total of 658 infants had laboratory-confirmed influenza: 20 (0.84/1000) born to women reporting immunization and 638 (2.83/1000) born to unimmunized women (RR 0.30; 95% CI, 0.19-0.46; P < .001). A total of 151 infants with laboratory-confirmed influenza were hospitalized: 3 (0.13/1000) born to women reporting immunization and 148 (0.66/1000) born to unimmunized women (RR 0.19; 95% CI, 0.06-0.60; P = .005).

CONCLUSIONS

Self-reported influenza immunization during pregnancy was low but increased after the H1N1 pandemic. Infants born to women reporting influenza immunization during pregnancy had risk reductions of 64% for ILI, 70% for laboratory-confirmed influenza, and 81% for influenza hospitalizations in their first 6 months. Maternal influenza immunization during pregnancy is a public health priority.

Evaluation of delivery options for second-stage events

BACKGROUND

Cesarean delivery in the second stage of labor is common, whereas the frequency of operative vaginal delivery has been declining. However, data comparing outcomes for attempted operative vaginal delivery vs cesarean in the second stage are scant. Previous studies that examine operative vaginal delivery have compared it to a baseline risk of complications from a spontaneous vaginal delivery and cesarean delivery. However, when a woman has a need for intervention in the second stage, spontaneous vaginal delivery is not an option she or the provider can choose. Thus, the appropriate clinical comparison is cesarean vs operative vaginal delivery.

OBJECTIVE

Our objective was to compare outcomes by the first attempted operative delivery (vacuum, forceps vs cesarean delivery) in patients needing second-stage assistance at a fetal station of +2 or below.

STUDY DESIGN

We conducted secondary analysis of an observational obstetric cohort in 25 academically affiliated US hospitals over a 3-year period. A subset of ≥37 weeks, nonanomalous, vertex, singletons, with no prior vaginal delivery who reached a station of +2 or below and underwent an attempt at an operative delivery were included. Indications included for operative delivery were: failure to descend, nonreassuring fetal status, labor dystocia, or maternal exhaustion. The primary outcomes included a composite neonatal outcome (death, fracture, length of stay ≥3 days beyond mother's, low Apgar, subgaleal hemorrhage, ventilator support, hypoxic encephalopathy, brachial plexus injury, facial nerve palsy) and individual maternal outcomes (postpartum hemorrhage, third- and fourth-degree tears [severe lacerations], and postpartum infection). Outcomes were examined by the 3 attempted modes of delivery. Odds ratios (OR) were calculated for primary outcomes adjusting for confounders. Final mode of delivery was quantified.

RESULTS

In all, 2531 women met inclusion criteria. No difference in the neonatal composite outcome was observed between groups. Vacuum attempt was associated with the lowest frequency of maternal complications (postpartum infection 0.2% vs 0.9% forceps vs 5.3% cesarean, postpartum hemorrhage 1.4% vs 2.8% forceps vs 3.8% cesarean), except for severe lacerations (19.1% vs 33.8% forceps vs 0% cesarean). When confounders were taken into account, both forceps (OR, 0.16; 95% confidence interval, 0.05-0.49) and vacuum (OR, 0.04; 95% confidence interval, 0.01-0.17) were associated with a significantly lower odds of postpartum infection. The neonatal composite and postpartum hemorrhage were not significantly different between modes of attempted delivery. Cesarean occurred in 6.4% and 4.4% of attempted vacuum and forceps groups (P = .04).

CONCLUSION

In patients needing second-stage delivery assistance with a station of +2 or below, attempted operative vaginal delivery was associated with a lower frequency of postpartum infection, but higher frequency of severe lacerations.

Carpenter-Coustan Compared With National Diabetes Data Group Criteria for Diagnosing Gestational Diabetes

OBJECTIVE

Use of Carpenter-Coustan compared with National Diabetes Data Group criteria increases the number of women diagnosed with gestational diabetes mellitus (GDM) by 30-50%, but whether treatment of this milder GDM reduces adverse outcomes is unknown. We explored the effects of the diagnostic criteria used on the benefits of GDM treatment.

METHODS

This was a secondary analysis of a randomized trial for treatment of mild GDM diagnosed using Carpenter-Coustan criteria. We evaluated the effect of treatment within two mutually exclusive diagnostic groups: 1) women who met the stricter National Diabetes Data Group as well as Carpenter-Coustan criteria (National Diabetes Data Group), and 2) those diagnosed by Carpenter-Coustan but not meeting National Diabetes Data Group criteria (Carpenter-Coustan only). Maternal outcomes examined were pregnancy-induced hypertension, shoulder dystocia, maternal weight gain, and cesarean delivery. Neonatal outcomes were large for gestational age, macrosomia (greater than 4,000 g), fat mass, small for gestational age, and a composite outcome of perinatal death, birth injury, hypoglycemia, hyperbilirubinemia, and hyperinsulinemia. Analysis of variance or the Breslow-Day test, as appropriate, was used to test for the interaction between diagnostic criteria and GDM treatment on the outcomes of interest.

RESULTS

Of 958 patients, 560 (58.5%) met National Diabetes Data Group criteria and 398 (41.5%) met Carpenter-Coustan only. Compared with untreated women, the direction of treatment effect did not differ by diagnostic criteria used and was consistent with the original trial. The P value for interaction between diagnostic criteria and treatment status was not significant for any outcome.

CONCLUSION

The overall beneficial treatment effect on pregnancy-induced hypertension, shoulder dystocia, cesarean delivery, and macrosomia was seen in patients diagnosed by the higher National Diabetes Data Group and by the lower thresholds of the Carpenter-Coustan criteria.

Patient Counseling and Preferences for Elective Repeat Cesarean Delivery

Objective We sought to identify factors influencing a woman's decision to have an elective repeat cesarean delivery (ERCD) versus vaginal birth after cesarean (VBAC). Methods and Materials A prospective study at two academic medical centers of women with one prior cesarean, and no contraindication to a trial of labor, delivered by ERCD from October 2013 to June 2014. Participants completed anonymous surveys during their delivery hospitalization. Counseling was considered adequate if women reported being counseled, recalled being quoted a VBAC success probability, and this probability was within 20% of that derived from an established VBAC success prediction model. Participants were also asked why they chose ERCD. Results Of 68 participants, only 8 (11.8%) had adequate counseling. Of those with inadequate counseling, 21.7% did not recall being counseled, 63.3% were not quoted a chance of success, and 60.0% had more than a 20% discrepancy between their recalled and predicted success rates. Eighteen women were calculated to have more than 70% chance of successful VBAC. Of these, 16 (88.9%) were not adequately counseled. Conclusion Most women were inadequately counseled about delivery options. The most important factors influencing the choice of ERCD over VBAC were patient preferences, risk for fetal injury, and perceived physician preference.

Pregnancy-Associated Hypertension in Glucose-Intolerant Pregnancy and Subsequent Metabolic Syndrome

OBJECTIVE

To evaluate whether pregnancy-associated hypertension (preeclampsia or gestational hypertension) among women with varying degrees of glucose intolerance during pregnancy is associated with maternal metabolic syndrome 5-10 years later.

METHODS

This was an observational cohort study of women previously enrolled in a treatment trial of mild gestational diabetes mellitus or an observational study of lesser degrees of glucose intolerance evaluated 5-10 years after their index pregnancy. At follow-up, women underwent anthropometric and blood pressure measurements and analysis of fasting glucose and serum lipids.

RESULTS

A total of 825 women (47% of eligible women from the original study) were included in this analysis and evaluated at a median 7 years after their index pregnancy at a median age of 35 years. Overall, 239 (29%) had subsequent metabolic syndrome. The frequency of metabolic syndrome and its components was highest in the women who had pregnancy-associated hypertension and delivered preterm. After adjusting for confounding factors, pregnancy-associated hypertension in women who delivered preterm was associated with subsequent hypertension (130/85 mm Hg or greater; relative risk 3.06, 95% confidence interval [CI] 1.95-4.80, P<.001), high triglycerides (150 mg/dL or greater; relative risk 1.82, 95% CI 1.06-3.14, P=.03), and metabolic syndrome (per the American Heart Association and National Heart Lung and Blood Institute Scientific Statement; relative risk 1.78, 95% CI 1.14-2.78, P=.01) compared with women who remained normotensive throughout their index pregnancy and were delivered at term.

CONCLUSION

Women with varying degrees of glucose intolerance who experienced pregnancy-associated hypertension and then delivered preterm had a higher frequency of subsequent hypertension, high triglycerides, and metabolic syndrome 5-10 years later.

Association of the Duration of Active Pushing With Obstetric Outcomes

OBJECTIVE

To estimate the associations between the duration of active pushing during the second stage of labor and maternal and neonatal outcomes.

METHODS

We performed an observational study in which data were obtained by trained abstractors from maternal and neonatal charts of deliveries at 25 hospitals over a 3-year period. In this secondary analysis, women with no prior cesarean delivery who had a term, singleton, cephalic gestation and reached complete dilation were analyzed. The duration of pushing, defined as the time from initiation of pushing to either vaginal delivery or the decision to proceed with a cesarean delivery, was determined. The primary maternal outcome was cesarean delivery and the primary neonatal outcome was a composite that included: mechanical ventilation, proven sepsis, brachial plexus palsy, clavicular fracture, skull fracture, other fracture, seizures, hypoxic-ischemic encephalopathy, or death. Nulliparous and parous women were analyzed separately in univariable and then multivariable analyses.

RESULTS

A total of 53,285 women were analyzed. In both nulliparous and parous women, longer duration of pushing was associated with increased odds of both cesarean delivery and the neonatal adverse outcome composite. Nevertheless, even after 4 hours of pushing, approximately 78% of nulliparous women who continued with active pushing had a vaginal delivery and more than 97% did not have the composite adverse neonatal outcome. Similarly, after more than 2 hours of pushing, approximately 82% of parous women who continued active pushing delivered vaginally and more than 97% did not have the adverse neonatal outcome.

CONCLUSION

A longer duration of pushing is associated with an increased relative risk, but small absolute difference in risk, of neonatal complications. Approximately 78% of nulliparous women delivered vaginally even after 4 hours of pushing.

Predictors of response to 17-alpha hydroxyprogesterone caproate for prevention of recurrent spontaneous preterm birth

BACKGROUND

Prematurity is the leading cause of neonatal morbidity and death among nonanomalous neonates in the United States. Intramuscular 17-alpha hydroxyprogesterone caproate injections reduce the risk of recurrent prematurity by approximately one third. Unfortunately, prophylactic 17-alpha hydroxyprogesterone caproate is not always effective, and one-third of high-risk women will have a recurrent preterm birth, despite 17-alpha hydroxyprogesterone caproate therapy. The reasons for this variability in response are unknown. Previous investigators have examined the influence of a variety of factors on 17-alpha hydroxyprogesterone caproate response but have analyzed data that used a fixed outcome of term delivery to define progesterone response.

OBJECTIVE

We hypothesized that the demographics, history, and pregnancy course among women who deliver at a similar gestational age with 17-alpha hydroxyprogesterone caproate for recurrent spontaneous preterm birth prevention differs when compared with those women who deliver later with 17-alpha hydroxyprogesterone caproate and that these associations could be refined by the use of a contemporary definition of 17-alpha hydroxyprogesterone caproate "responder."

STUDY DESIGN

This was a planned secondary analysis of a prospective, multicenter, longitudinal study of women with ≥1 previous documented singleton spontaneous preterm birth at <37 weeks gestation. Data were collected at 3 prespecified gestational age epochs during pregnancy. All women who were included in this analysis received 17-alpha hydroxyprogesterone caproate during the studied pregnancy. We classified women as a 17-alpha hydroxyprogesterone caproate responder or nonresponder by calculating the difference in delivery gestational age between the 17-alpha hydroxyprogesterone caproate-treated pregnancy and her earliest spontaneous preterm birth. Responders were defined as those with pregnancy that extended ≥3 weeks later with 17-alpha hydroxyprogesterone caproate, compared with the delivery gestational age of their earliest previous spontaneous preterm birth. Data were analyzed with the use of chi-square test, t-test, and logistic regression.

RESULTS

One hundred fifty-five women met the inclusion criteria. The 118 responders delivered later on average (37.7 weeks gestation) than the 37 nonresponders (33.5 weeks gestation; P < .001). Among responders, 32% (38/118 women) had a recurrent spontaneous preterm birth. Demographics (age, race/ethnicity, education, and parity) were similar between groups. In the regression model, the gestational age of the previous spontaneous preterm birth (odds ratio, 0.68; 95% confidence interval, 0.56-0.82; P < .001), vaginal bleeding/abruption in the current pregnancy (odds ratio, 0.24; 95% confidence interval, 0.06-0.88; P = .031), and first-degree family history of spontaneous preterm birth (odds ratio, 0.37; 95% confidence interval, 0.15-0.88; P = .024) were associated with response to 17-alpha hydroxyprogesterone caproate. Because women with a penultimate preterm pregnancy were more likely to be 17-alpha hydroxyprogesterone caproate nonresponders, we performed an additional limited analysis examining only the 130 women whose penultimate pregnancy was preterm. In regression models, the results were similar to those in the main cohort.

CONCLUSION

Several historic and current pregnancy characteristics define women who are at risk for recurrent preterm birth at a similar gestational age, despite 17-alpha hydroxyprogesterone caproate therapy. These data should be studied prospectively in larger cohorts and combined with genetic and environmental data to identify women who are most likely to benefit from this intervention.