Race and ethnicity are among the predisposing factors for fetal malpresentation at term.

OBJECTIVE: Fetal malpresentation complicates approximately 3% to 4% of all term births. It requires special considerations for delivery and exposes the mother and neonate to obstetrical interventions and potential adverse outcomes, such as umbilical cord prolapse, head entrapment and birth trauma, hypoxic ischemic encephalopathy, cesarean delivery, and cesarean delivery-related complications. We set out to explore the maternal and fetal factors associated with noncephalic malpresentation at term, with specific interest on the impact of maternal race and ethnicity on fetal malpresentation. STUDY DESIGN: This was a retrospective analysis of the Centers for Disease Control and Prevention Natality Live Birth database for the years from 2016 through 2018. All term, singleton deliveries for the following racial and ethnic groups were included: non-Hispanic White, non-Hispanic Black, Asian, and Hispanic. Race and ethnicity were assigned based on self-identification and individuals with >1 racial category were excluded from the analysis. Malpresentation was defined as a noncephalic presentation at term and included breech and transverse presentations. The malpresentation group included all noncephalic births and cephalic births that occurred following successful external cephalic version, whereas all other cephalic births served as controls. A multivariable logistic regression analysis was used to assess the rate of malpresentation, with adjustment for potential confounders including maternal age, race and ethnicity, parity, birthweight, fetal malformations, malformations of the central nervous system (CNS), and chromosomal anomalies. The results are displayed as adjusted odds ratios (aORs) with 95% confidence intervals (CIs). Statistical significance was set at a P value of <.05. Institutional review board approval was not required because the de-identified data are publicly available through a data use agreement. RESULTS: There were 9,692,203 term, singleton births during the study period. The malpresentation group included 354,689 births (3.66% of the total). The Table shows the rate of malpresentation for various maternal and fetal factors. We found a substantial racial and ethnic disparity in the malpresentation rates. Non-Hispanic White women had the highest malpresentation risk, whereas non-Hispanic Black women had the lowest risk (3.93% vs 2.81%; aOR, 1.38; 95% CI, 1.36-1.39). Hispanic and Asian women were also at increased risk for malpresentation when compared with non-Hispanic Black women (aOR, 1.30; 95% CI, 1.29-1.32 and aOR, 1.12; 95% CI, 1.10-1.14, respectively). In addition, several maternal and fetal conditions were noted to be associated with an increased risk for malpresentation at term, including older maternal age (aOR, 2.81; 95% CI, 2.74-2.88; for patients >40 years), nulliparity (aOR, 1.50; 95% CI, 1.48-1.51), low birthweight (aOR, 1.80; 95% CI, 1.77-1.83 for birthweight under 2500 g), and fetal malformations of the CNS and chromosomal anomalies (aOR, 3.53; 95% CI, 3.06-4.06 and aOR, 2.32; 95% CI, 2.05-2.63, respectively). CONCLUSION: Based on a large US population database, we identified several maternal, fetal, and racial and ethnic factors that are associated with an increased rate of noncephalic malpresentation at term. Specifically, fetal CNS malformations, congenital or chromosomal anomalies, advanced maternal age, low birthweight, and nulliparity are risk factors for noncephalic presentation. Interestingly, non-Hispanic White women have the highest risk for malpresentation, whereas non-Hispanic Black women have the lowest risk. Previous publications found that low birthweight, advanced maternal age, nulliparity, and congenital fetal malformations are risk factors for malpresentation.1-3 Nonetheless, the current data available on race and ethnicity are sporadic, with limited reports suggesting that sub-Saharan ethnicity is associated with a lower rate of malpresentation2 and that White race is associated with a higher rate.4 We present a large-scale, nationwide US-based study to confirm the racial and ethnic disparity regarding malpresentation in the United States. This may be explained by the known variation in the shape of the bony birth canal in different racial and ethnic groups and populations from different geographic locations.5 Further investigation is needed to explore the racial and ethnic disparity described.

Planned home birth and the association with neonatal hypoxic ischemic encephalopathy.

OBJECTIVE: To evaluate the association between planned home birth and neonatal hypoxic ischemic encephalopathy (HIE). METHODS: This is a case-control study in which a database of neonates who underwent head cooling for HIE at our institution from 2007 to 2011 was linked to New York City (NYC) vital records. Four normal controls per case were then randomly selected from the birth certificate data after matching for year of birth, geographic location, and gestational age. Demographic and obstetric information was obtained from the vital records for both the cases and controls. Location of birth was analyzed as hospital or out of hospital birth. Details from the out of hospital deliveries were reviewed to determine if the delivery was a planned home birth. Maternal and pregnancy characteristics were examined as covariates and potential confounders. Logistic regression was used to determine the odds of HIE by intended location of delivery. RESULTS: Sixty-nine neonates who underwent head cooling for HIE had available vital record data on their births. The 69 cases were matched to 276 normal controls. After adjusting for pregnancy characteristics and mode of delivery, neonates with HIE had a 44.0-fold [95% confidence interval (CI) 1.7-256.4] odds of having delivered out of hospital, whether unplanned or planned. Infants with HIE had a 21.0-fold (95% CI 1.7-256.4) increase in adjusted odds of having had a planned home birth compared to infants without HIE. CONCLUSION: Out of hospital birth, whether planned home birth or unplanned out of hospital birth, is associated with an increase in the odds of neonatal HIE.

Impact of non-steroidal anti-inflammatory drugs on hypertensive disorders of pregnancy.

OBJECTIVE: Non-steroidal anti-inflammatory drug (NSAID) use has the potential to adversely affect blood pressure in women with hypertensive disorders of pregnancy. We sought to evaluate this association. STUDY DESIGN: Women affected with severe hypertensive disorders of pregnancy were identified by retrospective chart review. The medication administration record was then used to identify controls (no NSAID exposure) until a sufficient number of patients were obtained, after which the cases (NSAID exposed) were identified in a chronological manner during the same study period until a 2:1 ratio was achieved. The primary outcome was the change in mean of all postpartum mean arterial pressures (MAP) throughout the hospital stay. Power analysis showed that 146 exposed and 73 unexposed subjects were necessary to obtain 90% power to detect a MAP difference of 10mmHg between the groups. Secondary outcomes included: initiation of anti-hypertensive medication, need for increased doses of anti-hypertension medication, and adverse events related to hypertension. RESULTS: 223 women had severe hypertensive disorders of pregnancy, of whom 75 (34%) were not exposed to NSAIDs and 148 (66%) were exposed. NSAID exposure was not associated with a difference in the average MAP postpartum (p=0.70), nor any of the secondary outcomes evaluated. Exposure to NSAIDs was less likely as serum creatinine increased (p=0.012). CONCLUSION: In women with severe hypertensive disorders of pregnancy, NSAIDs did not appear to increase the average postpartum MAP, increase the requirement for anti-hypertensive medications, or increase the rate of adverse postpartum events.

Are age cutoffs still used to identify candidates for invasive testing for chromosomal abnormalities?

OBJECTIVE: Our objective was to determine whether women > or = age 35 are more likely to undergo invasive testing after risk adjustment as compared with younger women at similar adjusted risk. STUDY DESIGN: Results of first-trimester combined aneuploidy risk assessment of singleton pregnancies from 2007-2008 were reviewed. For each level of adjusted risk, the rate of invasive testing (CVS or amniocentesis) was compared for those < age 35 and those > or = age 35. Spearman correlation, Fisher's exact test, and chi2 for trend were used for statistical comparison. RESULTS: For all categories except adjusted risk of 1 in < or = 250, women > or = age 35 were significantly more likely to undergo invasive testing as compared with younger women of similar risk. In women > or = age 35 with low adjusted risk, we observed a trend towards lower rates of invasive testing over time. CONCLUSION: The higher rate of invasive testing in those > or = 35 indicates that women are still being categorized based on age, though our data suggest this may be decreasing.