Singleton Stillbirths Research Articles

Racial/ethnic disparity in severe maternal morbidity among women who conceived by in vitro fertilization

BackgroundIn vitro fertilization (IVF) as a fertility treatment is associated with adverse perinatal outcomes. Racial/ethnic disparity in severe maternal morbidity (SMM) in women who conceived by IVF is understudied. ObjectiveTo examine differences in the association between race/ethnicity and SMM between women who conceived spontaneously and those who conceived using IVF. MethodsWe included all singleton live births and stillbirths in the United States, 2016–2021; data were obtained from the National Center for Health Statistics. Maternal race/ethnicity included non-Hispanic White (NHW), non-Hispanic Black (NHB), American Indian and Alaska Native (AIAN), Asian, Pacific Islander (PI), Hispanic, and mixed-race categories. The SMM composite outcome included eclampsia, uterine rupture, peripartum hysterectomy, blood transfusion, and intensive care unit (ICU) admission. We used logistic regression to adjust for potential confounders (such as age, education, parity, prepregnancy body mass index, smoking during pregnancy, chronic hypertension, and preexisting diabetes) and to assess modification of the association between race/ethnicity and SMM by IVF. ResultsThe study population included 21,585,015 women: 52% were NHW, 15% NHB, 0.8% AIAN, 6% Asian, 0.2% PI, 24% Hispanic, and 2% were of mixed race. IVF was used by 183,662 (0.85%) women; the rate of the SMM composite outcome was 18.5 per 1000 deliveries and 7.9 per 1000 deliveries in the IVF and spontaneous conception groups, respectively (unadjusted rate ratio 2.34, 95% confidence interval [CI] 2.26–2.43). In women with spontaneous conception, NHB, Asian and mixed-race women had elevated odds of SMM compared with NHW women (adjusted odds ratio [aOR]=1.39, 95% CI 1.37–1.41; aOR=1.04, 95% CI 1.02–1.07; and aOR=1.42, 95% CI 1.38–1.46, respectively). Racial/ethnic disparities in SMM and its components were not different between the IVF and spontaneous conception groups for the mixed-race category. NHB and Hispanic women had significantly higher aORs for uterine rupture/intrapartum hysterectomy compared with NHW women in the IVF group, while Asian women had a higher aOR for ICU admission compared with NHW women in the IVF group. ConclusionWomen who conceived by IVF have a greater than two-fold higher risk of SMM and this higher risk is evident across all racial/ethnic groups. However, NHB and Hispanic women who conceived by IVF had a higher risk of uterine rupture/hysterectomy, and Asian women who conceived by IVF had a higher risk of ICU admission. Our results warrant further investigation examining pregnancy and postpartum care issues among racial/ethnic minority women who conceive using IVF.

Postpartum readmission risk: a comparison between stillbirths and live births

Stillbirth occurs more commonly among pregnant people with comorbid conditions and obstetrical complications. Stillbirth also independently increases maternal morbidity and imparts a psychosocial hazard when compared with live birth. These distinct needs and burden may increase the risk for postpartum readmission after stillbirth. This study aimed to examine the risk for maternal postpartum readmission after stillbirth in comparison with live birth and to identify indications for readmission and the associated risk factors. This was a retrospective cohort of patients with singleton stillbirths or live births, delivered at ≥20 weeks' gestation, who were identified from the 2019 Nationwide Readmissions Database. The primary outcome was all-cause readmission within 6 weeks of discharge from the childbirth hospitalization. The association between stillbirth (vs live birth) and risk for readmission was assessed using multivariable regression models with adjustment for maternal age, sociodemographic characteristics, maternal and obstetrical conditions, and delivery characteristics. Within the stillbirth group, risk factors for readmission were further examined using multivariable regression. The secondary outcomes included principal indication for readmission (categorized based on principal diagnosis code of the readmission hospitalization) and timing of readmission (number of weeks after childbirth hospitalization). Differences in these secondary outcomes were compared between the stillbirth and live birth groups using chi-square tests. All analyses accounted for the complex sample design to generate nationally representative estimates. Postpartum readmission occurred in 2.7% of 16,636 patients with stillbirths, whereas it occurred in 1.6% of 2,870,677 patients with live births (unadjusted risk ratio, 1.65; 95% confidence interval, 1.47-1.86). The higher risk for readmission after stillbirth (vs live birth) persisted after adjusting for maternal, obstetrical, and delivery characteristics (adjusted risk ratio, 1.27; 95% confidence interval, 1.11-1.46). The distribution of principal indication for readmission differed after stillbirth and after live birth and included hypertension (30.2% vs 39.5%; unadjusted risk ratio, 0.76; 95% confidence interval, 0.63-0.93), mental health or substance use disorders (6.8% vs 3.6%; unadjusted risk ratio, 1.90; 95% confidence interval, 1.15-3.16), and venous thromboembolism (5.8% vs 2.0%; unadjusted risk ratio, 2.87; 95% confidence interval, 1.60-5.17). Among patients with stillbirths, 56.0% of readmissions occurred within 1 week, 71.8% within 2 weeks, and 88.1% within 4 weeks; the timing of readmission did not differ significantly between the stillbirth and live birth cohorts. Pregestational diabetes (adjusted risk ratio, 1.87; 95% confidence interval, 1.20-2.93), gestational diabetes (adjusted risk ratio, 1.67; 95% confidence interval, 1.03-2.71), hypertensive disorders of pregnancy (adjusted risk ratio, 1.80; 95% confidence interval, 1.31-2.47), obesity (adjusted risk ratio, 1.46; 95% confidence interval, 1.01-2.12), and primary cesarean delivery (adjusted risk ratio, 1.74; 95% confidence interval, 1.17-2.58) were associated with a higher risk for readmission after stillbirth, whereas higher household income was associated with a lower risk for readmission (eg, adjusted risk ratio for income ≥$82,000 vs $1-$47,999, 0.48; 95% confidence interval, 0.30-0.77). When compared with live births, the risk for postpartum readmission was higher after stillbirths, even after adjustment for differences in the patient demographic and clinical characteristics. Readmission for mental health or substance use disorders and venous thromboembolism is more common after stillbirths than after live births.

Etiology of stillbirth in a tertiary care center: a retrospective cohort study assessing ultrasound, laboratory, and pathology investigations

Background Canadian stillbirth data are limited, and a significant proportion of pregnancies resulting in stillbirth have no attributable cause. The objective of this study was to characterize stillbirth case investigations and management at a tertiary care hospital in Ontario, Canada. Methods This was a retrospective chart review study of all cases of singleton stillbirth at The Ottawa Hospital between 1 January 2012 and 31 December 2017. Terminations and multiples stillbirths were excluded. Chart reviews were conducted to extract maternal sociodemographic, obstetrical, and fetal characteristics, including results from antenatal ultrasounds, autopsy, placenta pathology, and laboratory investigations. Results A total of 155 eligible cases of stillbirth were identified, resulting in a 6-year stillbirth rate of 4.2 per 1000 total births. The median maternal age was 31.0 years (IQR: 29.0, 35.0) and the median gestational age at delivery was 28 weeks (IQR: 24, 35). A total of 9 (5.8%) pregnant individuals had a history of previous stillbirth. Of the 155 stillbirths, 35% underwent the full suite of post-loss laboratory, placental, and fetal autopsy investigations. 63.2% of cases had post-loss laboratory investigations completed. 76% and 71% of cases had fetal autopsy and placenta pathology evaluations completed, respectively. Antenatal characteristics associated with stillbirth included fetal anomalies/genetic markers (27.1%), umbilical cord and placental anomalies (24.5%), fetal growth abnormalities (27.7%), cervical/uterine abnormalities (11.6%), and amniotic fluid abnormalities (25.1%). The most common autopsy findings included evidence of infection (22.7%), fetal anomalies (12.6%), and fetal hypoxia (10%). The most common placental pathology findings included features of placental insufficiency (21.8%), retroplacental abnormalities (16.3%), and umbilical cord accident/infarct (15.4%). Conclusions Our findings demonstrate that as many as two-thirds of singleton stillbirth cases at our center did not receive the post-perinatal loss investigations recommended by clinical practice guidelines. More thorough collection of post-stillbirth data at all levels (institutional, provincial, national) is warranted to improve our understanding of stillbirth epidemiology, etiology, and management in Canada.

Prenatal aneuploidy screening and its impact on stillbirth etiology evaluation.

Stillbirth impacts 1% of all pregnancies in the USA with the underlying cause often remaining unknown. The objective of this study was to identify if prenatal aneuploidy screening impacted patient agreement to stillbirth evaluation. We performed a retrospective cohort study of patients with a singleton stillbirth after 20 weeks of gestation between October 2017 and December 2021. Demographics and stillbirth evaluation were collected for all patients. Multivariable logistic regression was performed adjusting for variables that were significant in univariate analysis. A total of 81 persons experienced stillbirth during the study period. Approximately 59.3% of patients had prenatal aneuploidy screening: 39.5% integrated screening, 37.5% non-invasive prenatal testing (NIPT), and 22.9% quad screen. Prenatal genetic screening did not significantly impact patient agreement to placental pathology, serum laboratory evaluation, or fetal autopsy. Patients with NIPT were less likely to have genetic testing sent at the time of stillbirth compared to those with another aneuploidy screening (aOR 0.27, 95% CI 0.07-0.99). Prenatal aneuploidy screening was not associated with patient acceptance of stillbirth evaluation. However, patients with NIPT were less likely to pursue further genetic testing during stillbirth evaluation, so further education regarding the benefit of karyotype and microarray should be included in patient counseling.

Maternal and perinatal outcomes in primiparous singleton pregnancies conceived with assisted reproductive technology in British Columbia

ObjectiveTo evaluate the odds of developing adverse maternal and perinatal outcomes in primiparous singleton pregnancies conceived with assisted reproductive technology (ART) compared with pregnancies conceived without ART. Study designA retrospective population-based cohort study using data from the British Columbia Perinatal Data Registry. The population included primiparous women with singleton live or stillbirths delivering at or after 20 weeks’ gestation between April 1st 2008–March 31st, 2021. Women who conceived with ART were compared with those who conceived without ART. The main outcome measures were gestational diabetes, hypertensive disorders of pregnancy, preterm birth, low birth weight, neonatal intensive care unit admission, stillbirth, and 5-minute Apgar score. Adjusted odds ratios were calculated. ResultsThe study population included 191,059 primiparous women: 183,819 conceived without ART, 7,240 conceived using ART. After controlling for age, body mass index, pre-gestational diabetes, and smoking status, singleton pregnancies conceived by ART had significantly higher odds of gestational diabetes (OR 1.18, 95 % confidence interval [CI] 1.10–1.26) and hypertensive disorders of pregnancy (OR 1.39, 95 % CI 1.29–1.51). There were also significantly increased odds of preterm birth (OR 1.35, 95 % CI 1.25–1.46), low birth weight (OR 1.35, 95 % CI 1.23–1.49), and neonatal intensive care unit admission (OR 1.21, 95 % CI 1.11–1.32). There was not a statistically significant difference in the odds of stillbirth (OR 1.06, 95 % CI 0.72–1.57) or 5-minute Apgar score < 7 (OR 1.10, 95 % CI 0.97–1.26). ConclusionThere is an increased odds of developing several adverse maternal or neonatal outcomes in primiparous singleton pregnancies conceived by ART including gestational diabetes, hypertensive disorders of pregnancy, preterm birth, low birth weight, and increased incidence of neonatal intensive care unit admissions.

A flexible approach to modelling stillbirths using the foetuses at risk approach.

Survival analysis methods are increasingly used to model the gestational age-specific risk of perinatal phenomena such as stillbirth. To compare two types of survival analysis models, and highlight differences by estimating the relationships between pre-pregnancy BMI and gestational age-specific rates of stillbirth. The study was based on singleton live births and stillbirths in the United States in 2016-2017, with data obtained from the natality and fetal death files of the National Center for Health Statistics. We compared Cox regression versus piecewise exponential additive mixed models (PAMMs) for modelling the relationship between BMI and stillbirth across gestational age. In a second analysis, we illustrated the performance of both models for assessing the relationship between the trimester-specific number of cigarettes smoked, a time-dependent covariate, and stillbirth. The study population included 7,567,316 births, of which 42,739 were stillbirths (5.6 per 1000 total births). Stillbirth rates increased with increasing pre-pregnancy BMI and increasing gestational age. In analyses with BMI as a categorical variable, the Cox model and PAMM models yielded similar results. Analyses of BMI as a continuous variable also showed similar results when BMI associations were assumed to be linear, and the changes in gestational age-specific rates were modelled parametrically. However, results differed slightly when PAMMs, modelled with data-driven approaches, were used to estimate changes in BMI effects across gestational age; PAMMs provided a more nuanced modelling of time-varying effects. PAMM models showed an approximately linear increase in the effect of smoking on stillbirth with increasing gestational age. For survival analyses using the foetuses-at-risk approach, PAMMs provide a valuable alternative to the traditional Cox model, with increased modelling flexibility when proportional hazards assumptions are violated.

Placental inflammation and overweight or obesity in term singleton stillbirths in Stockholm County 2002-2018; a case control study.

Stillbirth is a severe pregnancy complication. Maternal obesity is one of the most important modifiable risk factors of stillbirth, yet the biological mechanisms behind this association remain unclear. The adipose tissue is an endocrine organ which, in persons with obesity, causes a hyperinflammatory state. The aim of this study was to investigate inflammation as a contributing mechanism to the risk of stillbirth in women with obesity and if there are possible signs of different BMI phenotypes with different risk. This was a case control study based on all cases of term singleton stillbirth without major fetal malformation in Stockholm County between 2002-2018. Placentas have been examined according to a standardized protocol. Placental inflammatory lesions were compared both between placentas from pregnancies with live born and stillborn infants with different class of body mass index (BMI) as well as among women with stillborn and live born infants with different classes of BMI, respectively. All inflammatory placental lesions were more common in placentas from women with stillbirth compared to placentas from women with live born infants. Vasculitis, funisitis and chronic villitis as well as overall fetal and maternal inflammatory response were present with a significantly increased proportion with increasing BMI in placentas from women with term stillbirth however, there were no differences between placentas from women in different BMI classes with term live born infants. Both acute and chronic inflammatory placental lesions were more common in cases of stillbirth compared to pregnancies with live born infants. There were increased proportions of both acute and chronic placental inflammation (vasculitis, chronic villitis, funisitis and overall fetal and maternal inflammatory response) with increasing BMI among cases with term stillbirth, however no differences among controls with term live born infants.

Validation of an ICD-9-Based Algorithm to Identify Stillbirth Episodes from Medicaid Claims Data.

In administrative data, accurate timing of exposure relative to gestation is critical for determining the effect of potential teratogen exposure on pregnancy outcomes. To develop an algorithm for identifying stillbirth episodes in the ICD-9-CM era using national Medicaid claims data (1999-2014). Unique stillbirth episodes were identified from clusters of medical claims using a hierarchy that identified the encounter with the highest potential of including the actual stillbirth delivery and that delineated subsequent pregnancy episodes. Each episode was validated using clinical detail on retrieved medical records as the gold standard. Among 220 retrieved records, 197 were usable for validation of 1417 stillbirth episodes identified by the algorithm. The positive predictive value (PPV) was 64.0% (57.3-70.7%) overall, 80.4% (73.8-87.1%) for inpatient episodes, 28.2% (14.1-42.3%) for outpatient-only episodes, and 20.0% (2.5-37.5%) for outpatient episodes with overlapping hospitalizations. The absolute difference between the dates of the algorithm-specified stillbirth delivery and the medical record-based event was 4.2±24.3 days overall, 1.7±7.7 days for inpatient episodes, 14.3±51.4 days for outpatient-only episodes, and 1.0±2.0 days for outpatient episodes that overlapped with a hospitalization. Excluding all outpatient episodes, as well as pregnancies involving multiple births, the PPV increased to 82.7% (76.8-89.8%). Our algorithm to identify stillbirths from administrative claims data had a moderately high PPV. Positive predictive value was substantially increased by restricting the setting to inpatient episodes and using only input diagnostic codes for singleton stillbirths.

The association between maternal stature and adverse birth outcomes and the modifying effect of race and ethnicity: a population-based retrospective cohort study

There are known differences in the risk of perinatal and maternal birth outcomes because of maternal factors, such as body mass index and maternal race. However, the association of maternal height with adverse birth outcomes and the potential differences in this relationship by race and ethnicity have been understudied. This study aimed to examine the association between maternal stature and adverse perinatal outcomes and the potential modification of the association by race and ethnicity. This retrospective cohort study was conducted using data on all singleton births in the United States in 2016 and 2017 (N=7,361,713) obtained from the National Center for Health Statistics. Short and tall stature were defined as <10th and >90th percentiles of the maternal height distribution (<154.9 and >172.7 cm, respectively). Race and ethnicity categories included non-Hispanic White, non-Hispanic Black, American Indian or Alaskan Native Asian or Pacific Islander, and Hispanic. The primary outcomes were preterm birth (<37 weeks of gestation), perinatal death, and composite perinatal death or severe neonatal morbidity. Logistic regression was used to obtain adjusted odds ratios and 95% confidence intervals with adjustment for confounding by maternal age, body mass index, and other factors. Multiplicative and additive effect modifications by race and ethnicity were assessed. The study population included 7,361,713 women with a singleton stillbirth or live birth. Short women had an increased risk of adverse outcomes, whereas tall women had a decreased risk relative to average-stature women. Short women had an increased risk of perinatal death and composite perinatal death or severe neonatal morbidity (adjusted odds ratios, 1.14 [95% confidence interval, 1.10-1.17] and 1.21 [95% confidence interval, 1.19-1.23], respectively). The association between short stature and perinatal death was attenuated in non-Hispanic Black women compared with non-Hispanic White women (adjusted odds ratio, 1.10 [95% confidence interval, 1.03-1.17] vs 1.26 [95% confidence interval, 1.19-1.33]). Compared with average-stature women, tall non-Hispanic White women had lower rates of preterm birth, perinatal death, and composite perinatal death or severe neonatal morbidity (adjusted odds ratios, 0.82 [95% confidence interval, 0.81-0.83], 0.95 [95% confidence interval, 0.91-1.00], and 0.90 [95% confidence interval, 0.88-0.93], respectively). The association between tall and average stature with perinatal death was reversed in Hispanic women (adjusted odds ratio, 1.27; 95% confidence interval, 1.12-1.44). Compared with average-stature women, all tall women had lower rates of preterm birth, particularly among non-Hispanic Black and Hispanic women. Relative to average-stature women, short women have an increased risk of adverse perinatal outcomes across all race and ethnicity groups; these associations were attenuated in Hispanic women and for some adverse outcomes in non-Hispanic Black and Asian women. Tall mothers have a lower risk of preterm birth in all racial and ethnic groups, whereas tall non-Hispanic White mothers have a lower risk of perinatal death or severe neonatal morbidity compared with average-stature women.

Severe Maternal Morbidity and Mortality Among Immigrant and Canadian-Born Women Residing Within Low-Income Neighborhoods in Ontario, Canada

Evidence indicates that immigrant women and women residing within low-income neighborhoods experience higher adversity during pregnancy. Little is known about the comparative risk of severe maternal morbidity or mortality (SMM-M) among immigrant vs nonimmigrant women living in low-income areas. To compare the risk of SMM-M between immigrant and nonimmigrant women residing exclusively within low-income neighborhoods in Ontario, Canada. This population-based cohort study used administrative data for Ontario, Canada, from April 1, 2002, to December 31, 2019. Included were all 414 337 hospital-based singleton live births and stillbirths occurring between 20 and 42 weeks' gestation, solely among women residing in an urban neighborhood of the lowest income quintile; all women were receiving universal health care insurance. Statistical analysis was performed from December 2021 to March 2022. Nonrefugee immigrant status vs nonimmigrant status. The primary outcome, SMM-M, was a composite outcome of potentially life-threatening complications or mortality occurring within 42 days of the index birth hospitalization. A secondary outcome was SMM severity, approximated by the number of SMM indicators (0, 1, 2 or ≥3 indicators). Relative risks (RRs), absolute risk differences (ARDs), and odds ratios (ORs) were adjusted for maternal age and parity. The cohort included 148 085 births to immigrant women (mean [SD] age at index birth, 30.6 [5.2] years) and 266 252 births to nonimmigrant women (mean [SD] age at index birth, 27.9 [5.9] years). Most immigrant women originated from South Asia (52 447 [35.4%]) and the East Asia and Pacific (35 280 [23.8%]) regions. The most frequent SMM indicators were postpartum hemorrhage with red blood cell transfusion, intensive care unit admission, and puerperal sepsis. The rate of SMM-M was lower among immigrant women (2459 of 148 085 [16.6 per 1000 births]) than nonimmigrant women (4563 of 266 252 [17.1 per 1000 births]), equivalent to an adjusted RR of 0.92 (95% CI, 0.88-0.97) and an adjusted ARD of -1.5 per 1000 births (95% CI, -2.3 to -0.7). Comparing immigrant vs nonimmigrant women, the adjusted OR of having 1 SMM indicator was 0.92 (95% CI, 0.87-0.98), the adjusted OR of having 2 indicators was 0.86 (95% CI, 0.76-0.98), and the adjusted OR of having 3 or more indicators was 1.02 (95% CI, 0.87-1.19). This study suggests that, among universally insured women residing in low-income urban areas, immigrant women have a slightly lower associated risk of SMM-M than their nonimmigrant counterparts. Efforts aimed at improving pregnancy care should focus on all women residing in low-income neighborhoods.

Prepregnancy body mass index and adverse perinatal outcomes in the presence of other maternal risk factors

High prepregnancy body mass index is one of the most common risk factors for adverse perinatal events. This study aimed to assess whether the association between maternal body mass index and adverse perinatal outcome is modified by other concomitant maternal risk factors. This was a retrospective cohort study of all singleton live births and stillbirths in the United States from 2016 to 2017, using data from the National Center for Health Statistics. Logistic regression was used to estimate the adjusted odds ratios and 95% confidence intervals between prepregnancy body mass index and a composite outcome of stillbirth, neonatal death, and severe neonatal morbidity. Modification of this association by maternal age, nulliparity, chronic hypertension, and prepregnancy diabetes mellitus was assessed on both multiplicative and additive scales. The study population included 7,576,417 women with singleton pregnancy; 254,225 (3.5%) were underweight, 3,220,432 (43.9%) had normal body mass index, 1,918,480 (26.1%) were overweight, and 1,062,177 (14.4%), 516,693 (7.0%), and 365,357 (5.0%) had class I, II, and III obesity, respectively. Rates of the composite outcome increased with increasing body mass index above normal values, compared with women with normal body mass index. Nulliparity (289,776; 38.6%), chronic hypertension (135,328; 1.8%), and prepregnancy diabetes mellitus (67,744; 0.89%) modified the association between body mass index and the composite perinatal outcome on both the additive and multiplicative scales. Nulliparous (vs parous) women had a higher rate of increase in adverse outcomes with increasing body mass index. For example, in nulliparous women, class III obesity was associated with 1.8-fold higher odds compared with normal body mass index (adjusted odds ratio, 1.77; 95% confidence interval, 1.73-1.83), whereas in parous women, the adjusted odds ratio was 1.35 (95% confidence interval, 1.32-1.39). Women with chronic hypertension or prepregnancy diabetes mellitus had higher outcome rates overall; however, the dose-response relationship with increasing body mass index was absent. Although the composite outcome rates increased with maternal age, the risk curves were relatively similar across obesity classes in all maternal age groups. Overall, underweight women had 7% higher odds of the composite outcome, and this increased to 21% in parous women. Women with elevated prepregnancy body mass index are at increased risk of adverse perinatal outcomes, and the magnitude of these risks differs by concomitant risk factors, including prepregnancy diabetes mellitus, chronic hypertension, and nulliparity. In particular, in woman with chronic hypertension or prepregnancy diabetes mellitus, there is no impact of increasing body mass index on adverse perinatal outcomes. However, overall rates remain high, and prepregnancy prevention of hypertension and diabetes mellitus should be emphasized among all women irrespective of body mass index.

Mode of conception and risk of spontaneous vs. provider-initiated preterm birth: population-based cohort study

To study the association between mode of conception and risk of preterm birth, including, spontaneous and provider-initiated subtypes. Population-based retrospective cohort study. Not applicable. All singleton livebirths and stillbirth in Ontario, Canada, 2006-2014. The main exposure was mode of conception, namely unassisted conception, infertility without fertility treatment (i.e., known infertility but conceived without assistance), ovulation induction (OI) or intrauterine insemination (IUI), and invitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). Modified Poisson regression generated risk ratios (RRs) and 95% confidence intervals for the association between exposure categories and preterm birth adjusted for clinically relevant covariates using a propensity score. The primary outcome was preterm birth <37 weeks, further categorized as spontaneous or provider-initiated subtypes. The secondary outcome was preterm birth <34 weeks. We included 732,810 singleton births born to 649,918 mothers, of which 646,926 (88.3%) were from an unassisted conception, 68,822 (9.4%) with infertility but no fertility treatment, 9,024 (1.2%) following OI/IUI, and 8,038 (1.1%) following IVF/ICSI. Preterm birth <37 weeks occurred among 6.0% of births by unassisted conception, 7.7% with infertility without fertility treatment, 8.0% with OI/IUI, and 10.8% following IVF/ICSI. Relative to unassisted conception, the unadjusted RR of provider-initiated preterm birth was 1.30 (1.26-1.33) in women with infertility without fertility treatment, 1.36 (1.26-1.45) after OI/IUI, and 1.82 (1.70-1.93) after IVF/ICSI. The corresponding adjusted RRs (aRR) were 1.23 (1.16-1.31), 1.48 (1.29-1.69), and 2.35 (2.09-2.64). The unadjusted RR of spontaneous preterm birth was 1.22 (1.18-1.27) in women with infertility without fertility treatment, 1.22 (1.12-1.34) after OI/IUI, and 1.47 (1.35-1.60) after IVF/ICSI. The corresponding aRR were 1.15 (1.10-1.19), 1.19 (1.09-1.31), and 1.40 (1.27-1.53). For preterm birth <34 weeks, the RRs followed a similar pattern as for preterm birth <37 weeks, with the exception of women with infertility without fertility treatment (aRR 1.08; confidence interval, 0.95-1.23). Infertility and receipt of fertility treatment are each associated with a higher risk of preterm birth, spontaneous and provider-initiated subtypes, even in singleton pregnancies. Strategies are needed to reduce the risk for preterm birth in these women.

Social Determinants of Health and Risk of Stillbirth in the United States.

Our aim was to evaluate the impact of social determinants of health (SDoH) risk factors on stillbirth among pregnancy-related hospitalizations in the United States. We conducted a cross-sectional analysis of delivery-related hospital discharges using annualized data (2016-2017) from the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample. The International Classification of Diseases, 10th Revision ICD-10-CM codes were used to select women with singleton stillbirth. Z-codes were utilized to identify SDoH risk factors and their subtypes. The association between SDoH risk factors and stillbirth was assessed using survey logistic regression models. We analyzed 8,148,646 hospitalizations, out of which 91,140 were related to stillbirth hospitalizations, yielding a stillbirth incidence of 1.1%. An increased incidence was observed for non-Hispanic (NH) Blacks (1.7%) when compared with NH Whites (1.0%). The incidence of stillbirth was greater in hospitalizations associated with SDoH risk factors compared with those without risk factors [2.0% vs. 1.1% (p <0.001)]. Among patients with SDoH risk factors, the rate of stillbirth was highest in those designated as NH other (3.0%). Mothers that presented with SDoH risk factors had a 60% greater risk of stillbirth compared with those without (odds ratio [OR] = 1.61 [95% confidence interval (CI) = 1.33-1.95], p < 0.001). The SDoH issues that showed the most significant risk for stillbirth were: occupational risk (OR = 7.05 [95% CI: 3.54-9.58], p < 0.001), upbringing (OR = 1.87 [95% CI: 1.23-2.82], p < 0.001), and primary support group and family (OR = 5.45 [95% 3.84-7.76], p < 0.001). We found pregnancies bearing SDoH risk factors to be associated with a 60% elevated risk for stillbirth. Future studies should target a variety of risk reduction strategies aimed at modifiable SDoH risk factors that can be widely implemented at both the population health level as well as in the direct clinical setting. · Health disparities exist in stillbirth rates, especially among NH Black women.. · Social determinants of health risk factors increase the risk of stillbirth.. · There is a need for further study on the impact of specific SDoH risk factors on stillbirth risk..

Associations of Congenital Heart Disease with Deprivation Index by Rural-Urban Maternal Residence: A Population-Based Retrospective Cohort Study in Ontario, Canada.

BackgroundThe risk of congenital heart disease (CHD) has been found to vary by maternal socioeconomic status (SES) and rural-urban residence. In this study, we examined associations of CHD with two maternal SES indicators and maternal rural-urban residence. ApproachThis was a population-based retrospective cohort study, including singleton stillbirths and live hospital births from April 1, 2012 to March 31, 2018 in Ontario, Canada. We linked the BORN data and Canadian Institute for Health Information databases. Multivariable logistic regression models were used to examine associations of CHD with material deprivation index (MDI), social deprivation index (SDI), and maternal residence while adjusting for maternal age at birth, parity, assisted reproductive technology, obesity, previous caesarean section, pre-existing health conditions, substance use during pregnancy, and infant’s sex. MDI and SDI were estimated at a dissemination area level and categorized into quintiles (Q1-Q5). ResultsThis cohort included 798,173 singletons. In maternal urban residence, the p trend (Cochran–Armitage test) was &lt; 0.0001 for both MDI and SDI; while for rural residence, it was 0.002 and 0.98, respectively. Infants living in the most materially deprived neighbourhoods (Q5) was associated with higher odd of CHD (aOR: 1.21, 95% CI: 1.12-1.29) compared to Q1. Similarly, infants living in the most socially deprived neighbourhoods (SDI Q5) had 18% increase in the odds of CHD (aOR: 1.18, 95% CI: 1.1-1.26) compared to Q1. Rural infants had 13% increase in the odds of CHD compared to their urban counterparts. After stratifying by maternal rural-urban residence, we still detected higher odds of CHD with two indices in urban residence but only MDI in rural residence. ConclusionHigher material and social deprivation and rural residence were associated with higher odds of CHD. Health interventions and policies should reinforce the need for optimal care for all families, particularly underprivileged families in both rural and urban regions.

Racial and ethnic differences in severe maternal morbidity among singleton stillbirth deliveries

Despite growing evidence suggesting racial or ethnic disparities in the risk of severe maternal morbidity among live births, there is little research investigating potential differences in severe maternal morbidity risk among stillbirths across race and ethnicity. This study aimed to compare the risk of severe maternal morbidity by race and ethnicity among patients with singleton stillbirth pregnancies. We used the California Linked Birth File database to perform a retrospective analysis of singleton stillbirth pregnancies delivered at 20 to 42 weeks' gestation between 2007 and 2011. The database contained information from fetal death certificates linked to maternal hospital discharge records. We defined severe maternal morbidity using the Centers for Disease Control and Prevention composite severe maternal morbidity indicator and compared rates of severe maternal morbidity across racial and ethnic groups. Multivariable regression analysis was used to examine how race and ethnicity were associated with severe maternal morbidity risk after accounting for the influence of patients' clinical risk factors, socioeconomic characteristics, and attributes of the delivery hospital. Of the 9198 patients with singleton stillbirths, 533 (5.8%) experienced severe maternal morbidity. Non-Hispanic Black patients had a significantly higher risk of severe maternal morbidity (10.6% vs 5.2% in non-Hispanic White patients, 5.2% in Hispanic patients, and 5.1% in patients with other race or ethnicity; P<.001). The higher risk of severe maternal morbidity among non-Hispanic Black patients persisted even after adjusting for patients' clinical, socioeconomic, and hospital characteristics (adjusted odds ratio for non-Hispanic Black vs non-Hispanic White patients, 1.74; 95% confidence interval, 1.21-2.50). Further analysis separating blood-transfusion and nontransfusion severe maternal morbidity showed a higher risk of blood transfusion in non-Hispanic Black patients, which remained significant after adjusting for patients' clinical, socioeconomic, and hospital characteristics (adjusted odds ratio for non-Hispanic Black vs non-Hispanic White patients, 1.64; 95% confidence interval, 1.11-2.43). However, the higher risk of nontransfusion severe maternal morbidity in non-Hispanic Black patients was no longer significant after adjusting for patients' clinical risk factors (adjusted odds ratio for non-Hispanic Black vs non-Hispanic White patients, 1.38; 95% confidence interval, 0.83-2.30). Severe maternal morbidity occurred in 5.8% of patients with a singleton stillbirth. Risk of severe maternal morbidity in stillbirth was higher in patients with non-Hispanic Black race, which was likely owing to a higher risk of hemorrhage, as evidenced by increased rate of blood transfusion.

Associations of congenital heart disease with deprivation index by rural-urban maternal residence: a population-based retrospective cohort study in Ontario, Canada

BackgroundThe risk of congenital heart disease (CHD) has been found to vary by maternal socioeconomic status (SES) and rural-urban residence. In this study, we examined associations of CHD with two maternal SES indicators and stratified the analysis by maternal rural-urban residence.MethodsThis was a population-based retrospective cohort study. We included all singleton stillbirths and live hospital births from April 1, 2012 to March 31, 2018 in Ontario, Canada. We linked the BORN Information System and Canadian Institute for Health Information databases. Multivariable logistic regression models were used to examine associations of CHD with material deprivation index (MDI), social deprivation index (SDI), and maternal residence while adjusting for maternal age at birth, assisted reproductive technology, obesity, pre-pregnancy maternal health conditions, mental health illness before and during pregnancy, substance use during pregnancy, and infant’s sex. MDI and SDI were estimated at a dissemination area level in Ontario and were categorized into quintiles (Q1-Q5).ResultsThis cohort study included 798,173 singletons. In maternal urban residence, the p trend (Cochran–Armitage test) was less than 0.0001 for both MDI and SDI; while for rural residence, it was 0.002 and 0.98, respectively. Infants living in the most materially deprived neighbourhoods (MDI Q5) had higher odds of CHD (aOR: 1.21, 95% CI: 1.12–1.29) compared to Q1. Similarly, infants living in the most socially deprived neighbourhoods (SDI Q5) had an 18% increase in the odds of CHD (aOR: 1.18, 95% CI: 1.1–1.26) compared to Q1. Rural infants had a 13% increase in the odds of CHD compared to their urban counterparts. After stratifying by maternal rural-urban residence, we still detected higher odds of CHD with two indices in urban residence but only MDI in rural residence.ConclusionHigher material and social deprivation and rural residence were associated with higher odds of CHD. Health interventions and policies should reinforce the need for optimal care for all families, particularly underprivileged families in both rural and urban regions. Future studies should further investigate the effect of social deprivation on the risk of CHD development.

Holding a baby after stillbirth: the impact of fetal congenital and structural abnormalities.

ObjectiveStillbirth can result in numerous adverse psychosocial sequelae. Recommendations vary with regard to holding the baby after a stillbirth. Few studies have addressed the impact of fetal abnormalities on these outcomes.Study designAnalyses of singleton stillbirths within the Stillbirth Collaborative Research Network were conducted. Patient and stillbirth characteristics were compared between those who did and did not hold their baby. Results from psychometric surveys were compared between cases with and without visible fetal anomalies.ResultThere were no significant differences between those who held and those who did not hold in any patient or stillborn characteristics. Visible fetal abnormalities were not associated with adverse psychological outcomes.ConclusionFetal abnormalities, including congenital and post-demise changes, do not differ between those who held and did not hold their baby after stillbirth. This suggests that patients should not be discouraged from holding their stillborn infant in the presence of visible abnormalities.

Maternal acute thermophysiological stress and stillbirth in Western Australia, 2000–2015: A space-time-stratified case-crossover analysis

The extreme thermal environment driven by climate change disrupts thermoregulation in pregnant women and may threaten the survival of the developing fetus. To investigate the acute effect of maternal exposure to thermophysiological stress (measured with Universal Thermal Climate Index, UTCI) on the risk of stillbirth and modification of this effect by sociodemographic disparities. We conducted a space-time-stratified case-crossover analysis of daily UTCI and 2835 singleton stillbirths between 1st January 2000 and 31st December 2015 across multiple small areas in Western Australia. Distributed lag non-linear models were combined with conditional quasi-Poisson regression to investigate the effects of the UTCI exposure from the preceding 6 days to the day of stillbirth. We also explored effect modification by fetal and maternal sociodemographic factors. The median UTCI was 13.9 °C (representing no thermal stress) while the 1st and 99th percentiles were 0.7 °C (slight cold stress) and 31.7 °C (moderate heat stress), respectively. Relative to median UTCI, we found positive associations between acute maternal cold and heat stresses and higher risks of stillbirth, increasing with the intensity and duration of the thermal stress episodes. The cumulative risk from the preceding 6 days to the day of stillbirth was stronger in the 99th percentile (RR = 1.19, 95% CI: 1.17, 1.21) than the 1st percentile (RR = 1.14, 95% CI: 1.12, 1.15), relative to the median UTCI. The risks were disproportionately higher in term and male stillborn fetuses, smoking, unmarried, ≤19 years old, non-Caucasian, and low socioeconomic status mothers. Acute maternal exposure to both cold and heat stresses may contribute to the risk of stillbirth and be exacerbated by sociodemographic disparities. The findings suggest public health attention, especially for the identified higher-risk groups. Future studies should consider the use of a human thermophysiological index, rather than surrogates such as ambient temperature.

Mode of Delivery in Antepartum Singleton Stillbirths and Associated Risk Factors.

This study was aimed to investigate delivery management of patients with antepartum stillbirth. Using data from fetal death certificates and linked maternal hospital discharge records, we identified a population-based sample of patients with singleton antepartum stillbirth at 20 to 42 weeks of gestation in California in 2007 to 2011. Primary outcomes were intended mode of delivery and actual mode of delivery. We used multivariable regressions to examine the association between patient demographic, clinical, and hospital characteristics and their mode of delivery. Separate analysis was performed for patients who had prior cesarean delivery versus those who did not. Of 7,813 patients with singleton antepartum stillbirth, 1,356 had prior cesarean, while 6,457 had no prior cesarean. Labor was attempted in 51.8% of patients with prior cesarean and 93.7% of patients without prior cesarean, with 76.2 and 95.8% of these patients, respectively, delivered vaginally. Overall, 18.9% of patients underwent a cesarean delivery (60.5% among those with prior cesarean and 10.2% among those without prior cesarean). Multivariable regression analysis identified several factors associated with the risk of cesarean delivery that were not medically indicated. For instance, among patients without prior cesarean, malpresentation (of which the vast majority was breech presentation) was associated with an increased likelihood of planned cesarean (adjusted odds ratio [OR] = 3.26, 95% confidence interval [CI]: 2.53-4.22) and cesarean delivery after attempting labor (adjusted OR = 3.09, 95% CI: 2.25-4.25). For both patients with and without prior cesarean, delivery at an urban teaching hospital was associated with a lower likelihood of planned cesarean and a lower likelihood of cesarean delivery after attempting labor (adjusted ORs ranged from 0.28 to 0.56, p < 0.001 for all). Over one in six patients with antepartum stillbirth underwent cesarean delivery. Among patients who attempted labor, rate of vaginal delivery was generally high, suggesting a potential opportunity to increase vaginal delivery in this population. · In singleton antepartum stillbirths, 18.9% underwent cesarean delivery.. · Rate of vaginal delivery was high when labor was attempted.. · Both clinical and non-clinical factors were associated with risk of cesarean delivery..

Stillbirth aftercare in a tertiary obstetric center- parents' experiences.

This study aimed to assess parents' satisfaction with received care and support when experiencing stillbirth. This was a questionnaire survey conducted at Helsinki University Hospital, Helsinki, Finland during 2016-2020. Separate questionnaires were sent to mothers and partners who had experienced an antepartum singleton stillbirth at or after 22 gestational weeks during 2016-2019. The questionnaire covered five major topics: stillbirth diagnosis, delivery, information on postmortem examinations, aftercare at the ward, and follow-up appointment. One hundred nineteen letters were sent and 57 (47.9%) of the mothers and 46 (38.7%) of their partners responded. Both mothers and their partners felt well supported during delivery. They were also satisfied with the time holding their newborn. Partners reported even higher satisfaction in this aspect with a significant within-dyad difference (p=0.049). Parents were generally pleased with the support at the ward. However, both groups were less satisfied with social worker counseling (mothers 53.7%, partners 61.0%). The majority felt that the follow-up visit was helpful. Nonetheless, a remarkable proportion felt that the follow-up visit increased their anxiousness (25.9%, 14.0%, p=0.018). Partners rated their mood higher than mothers (p=0.001). Open feedback revealed that the support received after discharge from hospital was often insufficient. Our study showed that the parents who experience stillbirth in our institution receive mostly adequate care and support during their hospital stay. However, there is room for further training of healthcare professionals and other professionals contributing in stillbirth aftercare.