Risk of stillbirth after a previous caesarean delivery: A Swedish nationwide cohort study.

OBJECTIVES: To investigate the risk of stillbirth in relation to (1) a previous caesarean delivery (CD) compared with those following a vaginal birth (VB); and (2) vaginal birth after caesarean (VBAC) compared with a repeat CD. DESIGN: Population-based cohort study. SETTING: The Swedish Medical Birth registry. POPULATION: Women with their first and second singletons between 1982 and 2012. METHODS: Multivariable logistic regression models were performed to estimate adjusted odds ratios (aOR) and 95% confidence intervals (CI) of the association between CD in the first pregnancy and stillbirth in the second pregnancy and the association between VBAC and stillbirth. Sub-group analyses were performed by types of CD and timing of stillbirth (antepartum and intrapartum). MAIN OUTCOME MEASURES: Stillbirth (antepartum and intrapartum fetal death). RESULTS: Of the 1 771 700 singleton births from 885 850 women, 117 114 (13.2%) women had a CD in the first pregnancy, and 51 755 had VBAC in the second pregnancy. We found a 37% increased odds of stillbirth (aOR 1.37; 95% CI 1.23-1.52) in women with a previous CD compared with VB. The odds of intrapartum stillbirth were higher in the previous pre-labour CD group (aOR 2.72; 95% CI 1.51-4.91) and in the previous in-labour CD group (aOR 1.35; 95% CI 0.76-2.40), although not statistically significant in the latter case. No increased odds were found for intrapartum stillbirth in women who had VBAC (aOR 0.99; 95% CI 0.48-2.06) compared with women who had a repeat CD. CONCLUSIONS: This study confirms that a CD is associated with an increased risk of subsequent stillbirth, with a greater risk among pre-labour CD. This association is not solely mediated by increases in intrapartum asphyxia, uterine rupture or attempted VBAC. Further research is needed to understand this association, but these findings might help healthcare providers to reach optimal decisions regarding mode of birth, particularly when CD is unnecessary.

Impact of Chronic Hypertension and Antihypertensive Treatment on Adverse Perinatal Outcomes: Systematic Review and Meta-Analysis.

Background Maternal chronic hypertension is associated with adverse pregnancy outcomes. Previous studies examined the association between either chronic hypertension or antihypertensive treatment and adverse pregnancy outcomes. We aimed to synthesize the evidence on the effect of chronic hypertension/antihypertensive treatment on adverse pregnancy outcomes. Methods and Results Medline/PubMed, EMBASE, and Web of Science were searched; we included observational studies and assessed the effect of race/ethnicity, where possible, following a registered protocol (CRD42019120088). Random-effects meta-analyses were used. A total of 81 studies were identified on chronic hypertension, and a total of 16 studies were identified on antihypertensive treatment. Chronic hypertension was associated with higher odds of preeclampsia (adjusted odd ratio [aOR], 5.43; 95% CI, 3.85-7.65); cesarean section (aOR, 1.87; 95% CI, 1.6-2.16); maternal mortality (aOR, 4.80; 95% CI, 3.04-7.58); preterm birth (aOR, 2.23; 95% CI, 1.96-2.53); stillbirth (aOR, 2.32; 95% CI, 2.22-2.42); and small for gestational age (SGA) (aOR, 1.96; 95% CI, 1.6-2.40). Subgroup analyses indicated that maternal race/ethnicity does not influence the observed associations. Women with chronic hypertension on antihypertensive treatment (versus untreated) had higher odds of SGA (aOR, 1.86; 95% CI, 1.38-2.50). Conclusions Chronic hypertension is associated with adverse pregnancy outcomes, and these associations appear to be independent of maternal race/ethnicity. In women with chronic hypertension, those on treatment had a higher risk of SGA, although the number of studies was limited. This could result from a direct effect of the treatment or because severe hypertension during pregnancy is a risk factor for SGA and women with severe hypertension are more likely to be treated. The effect of antihypertensive treatment on SGA needs to be further tested with large randomized controlled trials.

Pregnancy outcomes in women with chronic kidney disease and chronic hypertension: a National cohort study.

BACKGROUND: Maternal chronic kidney disease and chronic hypertension have been linked with adverse pregnancy outcomes. We aimed to examine the association between these conditions and adverse pregnancy outcomes over the last 3 decades. OBJECTIVE: We conducted this national cohort study to assess the association between maternal chronic disease (CH, CKD or both conditions) and adverse pregnancy outcomes with an emphasis on the effect of parity, maternal age, and BMI on these associations over the last three decades. We further investigated whether different subtypes of CKD had differing effects. STUDY DESIGN: We used data from the Swedish Medical Birth Register, including 2,788,490 singleton births between 1982 and 2012. Women with chronic kidney disease and chronic hypertension were identified from the Medical Birth Register and National Patient Register. Logistic regression models were performed to assess the associations between maternal chronic disease (chronic hypertension, chronic kidney disease, or both conditions) and pregnancy outcomes, including preeclampsia, in-labor and prelabor cesarean delivery, preterm birth, small for gestational age, and stillbirth. RESULTS: During the 30-year study period, 22,397 babies (0.8%) were born to women with chronic kidney disease, 13,279 (0.48%) to women with chronic hypertension and 1079 (0.04%) to women with both conditions. Associations with chronic hypertension were strongest for preeclampsia (adjusted odds ratio, 4.57; 95% confidence interval, 4.33-4.84) and stillbirth (adjusted odds ratio, 1.65; 95% confidence interval, 1.35-2.03) and weakest for spontaneous preterm birth (adjusted odds ratio, 1.07; 95% confidence interval, 0.96-1.20). The effect of chronic kidney disease varied from (adjusted odds ratio, 2.05; 95% confidence interval, 1.92-2.19) for indicated preterm birth to no effect for stillbirth (adjusted odds ratio, 1.16; 95% confidence interval, 0.95-1.43). Women with both conditions had the strongest associations for in-labor cesarean delivery (adjusted odds ratio, 1.86; 95% confidence interval, 1.49-2.32), prelabor cesarean delivery (adjusted odds ratio, 2.68; 95% confidence interval, 2.18-3.28), indicated preterm birth (adjusted odds ratio, 9.09; 95% confidence interval, 7.61-10.7), and small for gestational age (adjusted odds ratio, 4.52; 95% confidence interval, 3.68-5.57). The results remained constant over the last 3 decades. Stratified analyses of the associations by parity, maternal age, and body mass index showed that adverse outcomes remained independently higher in women with these conditions, with worse outcomes in multiparous women. All chronic kidney disease subtypes were associated with higher odds of preeclampsia, in-labor cesarean delivery, and medically indicated preterm birth. Different subtypes of chronic kidney disease had differing risks; strongest associations of preeclampsia (adjusted odds ratio, 3.98; 95% confidence interval, 2.98-5.31) and stillbirth (adjusted odds ratio, 2.73; 95% confidence interval, 1.13-6.59) were observed in women with congenital kidney disease, whereas women with diabetic nephropathy had the most pronounced increase odds of in-labor cesarean delivery (adjusted odds ratio, 3.54; 95% confidence interval, 2.06-6.09), prelabor cesarean delivery (adjusted odds ratio, 7.50; 95% confidence interval, 4.74-11.9), and small for gestational age (adjusted odds ratio, 4.50; 95% confidence interval, 2.92-6.94). In addition, women with renovascular disease had the highest increased risk of preterm birth in both spontaneous preterm birth (adjusted odds ratio, 3.01; 95% confidence interval, 1.57-5.76) and indicated preterm birth (adjusted odds ratio, 8.09; 95% confidence interval, 5.73-11.4). CONCLUSION: Women with chronic hypertension, chronic kidney disease, or both conditions are at an increased risk of adverse pregnancy outcomes which were independent of maternal age, body mass index, and parity. Multidisciplinary management should be provided with intensive clinical follow-up to support these women during pregnancy, particularly multiparous women. Further research is needed to evaluate the effect of disease severity on adverse pregnancy outcomes.

Association between hypertensive disorders of pregnancy and the risk of asthma, eczema and allergies in offspring: A systematic review and meta-analysis.

OBJECTIVE: Conduct a systematic review and meta-analysis examining the association between hypertensive disorders of pregnancy (HDP) and risk of asthma, eczema, food allergies and allergic rhinitis in the offspring. DESIGN: A systematic review and random-effects meta-analyses were used to synthesize the published literature. PRISMA guidelines were followed throughout. Two independent reviewers carried out data extraction and quality assessment of included studies. Grading of Recommendations Assessment, Development and Evaluation (GRADE) was used to assess certainty of findings. DATA SOURCES: A systematic search of PubMed, Embase, Web of Science and CINAHL was performed from inception of databases-21 April 2020, supplemented by hand-searching reference lists of included articles. ELIGIBILITY CRITERIA: Two reviewers independently reviewed titles, abstracts and full-text articles. English language, cohort, case-control and cross-sectional published studies examining the association between HDP (primary exposure: pre-eclampsia; secondary exposures: all other HDP) and asthma, eczema, food allergies and allergic rhinitis were included. RESULTS: Of the 2833 studies retrieved, 14 studies met inclusion criteria. Of these, 11 studies reported evidence of association between HDP and atopic disorders. Thirteen studies reported estimates for asthma. Seven of these included adjusted estimates (including 3 645 773 participants) for a pre-eclampsia-asthma relationship resulting in a pooled odds ratio (OR) of 1.14 (95% CI: 1.04, 1.26) (I2  = 62%). However, this OR was reduced to 1.08 (95% CI: (0.78, 1.48) when the large registry-based cohort studies were excluded, and only studies using parent-reported measures to determine a diagnosis of asthma were included. Four studies included adjusted estimates (including 254 998 participants) for other HDP and asthma (pooled OR: 1.02, 95% CI: 0.96, 1.09) (I2  = 0%). Two studies provided adjusted estimates (including 1 699 663 participants) for a pre-eclampsia-eczema relationship (pooled OR: 1.06, 95% CI: 0.98, 1.14) (I2  = 0%). One study including pre-eclampsia-food allergies was identified (OR: 1.28, 95% CI: 1.11, 1.46). Three studies examined a HDP (including pre-eclampsia) and allergic rhinitis relationship, with effect estimates ranging from 1.14 to 2.10. Studies were classified as low or low-moderate risk of bias, while GRADE certainty of findings were low to very low. CONCLUSIONS: While pre-eclampsia was associated with a possible increased risk of asthma in offspring, there was no evidence for a relationship between other HDP and asthma. There is a lack of published literature examining the association between HDP and eczema, food allergy and allergic rhinitis. Further primary research is warranted to gain a better understanding of the association between HDP and the risk of childhood atopic disease. SYSTEMATIC REVIEW REGISTRATION: Review protocol in appendix.

The impact of obstetric mode of delivery on childhood behavior.

PURPOSE: We investigated the hypothesis that mode of delivery affects childhood behavior and motor development and examined whether there are sex-specific associations, i.e., whether males and females have different risk estimates. METHODS: Families with infants born between December 2007 and May 2008 (N = 11,134) were randomly selected and recruited to the Growing Up in Ireland study. Mode of delivery was classified into spontaneous vaginal delivery; instrumental vaginal delivery; emergency Cesarean section (CS); and elective CS. The 'Ages and Stages Questionnaire' was completed at age 9-months and the 'Strengths and Difficulties Questionnaire' at 3 years. Data were weighted to represent the national sample (N = 73,662) and multivariate logistic regression was used for the statistical analyses. RESULTS: At age 9 months, elective CS was associated with a delay in personal social skills [adjusted odds ratio, aOR 1.24; (95% confidence interval, CI 1.04, 1.48)] and gross motor function [aOR 1.62, (95% CI 1.34, 1.96)], whereas emergency CS was associated with delayed gross motor function [aOR 1.30, (95% CI 1.06, 1.59)]. At age 3 years there was no significantly increased risk of an abnormal total SDQ score across all modes of delivery. CONCLUSIONS: Children born by elective CS may face a delay in cognitive and motor development at age 9 months. No increase in total SDQ score was found across all modes of delivery. Further investigation is needed to replicate these findings in other populations and explore the potential biological mechanisms.