Prevalence of and Risk Factors for Postpartum Anxiety in a Commercially-Insured United States Cohort

Abstract

Objective:

The primary objective of this study was to estimate the prevalence of new-onset anxiety diagnoses in the postpartum period. We also aimed to estimate the prevalence of psychiatric co-morbidities, explore changes by year, and identify risk factors for new-onset postpartum anxiety.

Methods:

This retrospective cohort study used the Merative ^™ Marketscan^® Commercial Database and included commercially-insured adult women ≥18 years of age who experienced delivery of a singleton or multiple gestation between 2008 and 2021 and did not have a pre-existing or prepregnancy diagnosis of depression, anxiety, or post-traumatic stress disorder (PTSD). The primary outcome was a new-onset anxiety diagnosis based on ICD-9 and 10 codes in the postpartum period (up to 12 months after childbirth). Secondary outcomes were co-morbid anxiety with depression and PTSD. We also estimated the prevalence of each psychiatric condition by year, and identified risk factors associated with postpartum anxiety. Univariable and multivariable regression models were constructed to identify risk factors.

Results:

From 1,469,121 individuals without prenatal mental health disorders, 84,984 individuals (5.8%, 95% CI 5.7-5.8%) were diagnosed with new-onset postpartum anxiety up to 12 months following childbirth, with 9,490 who were diagnosed in the first month and 75,494 between one-month and one-year postpartum. Co-morbid anxiety and depression, and anxiety and PTSD occurred in 18.0 (95% CI 17.8-18.2) and 0.9 (95% CI 0.9-1.0) per 1000 individuals of the study cohort, respectively. Prevalence of postpartum anxiety increased from 30.8 to 122.9 per 1000 individuals from 2008 to 2021 (P value for trend <0.001). Independent risk factors for new onset postpartum anxiety diagnosed between 1 to 12 months postpartum included: younger age, north central US residence, earlier gestational age at delivery, cesarean delivery, antenatal or early postpartum sleep disorders, severe maternal morbidity (including transfusion), neglected medical conditions, and neonatal complications.

Conclusions:

Postpartum anxiety was estimated to affect nearly 6% of commercially insured patients in the U.S. and has increased four-fold since 2008. Risk factors associated with postpartum anxiety may help to identify individuals at risk who could benefit from early intervention.

Precis:

Approximately 6% of commercially insured patients developed new-onset anxiety within one year of delivery, and the prevalence of postpartum anxiety diagnoses increased four-fold from 2008-2021.

Introduction

The World Health Organization describes current rates of maternal mortality as “unacceptably high”,¹ and the Centers for Disease Control and Prevention (CDC) identifies mental health conditions as the leading cause of pregnancy-related mortality in the United States (US).² Individuals with postpartum psychiatric presentations have a nearly 4-fold higher mortality ratio compared to mothers without psychiatric history, with these deaths accounting for 41% of fatalities.^3,4 Most existing perinatal mental health research and clinical practices have centered on identification and treatment of postpartum depression, with limited attention to anxiety disorders, which are independently associated with maternal morbidity and mortality.^5-9 Screening for postpartum anxiety disorders is inconsistent despite recommendations from the American College of Obstetricians and Gynecologists (ACOG) and the United States Preventive Services Task Force (USPSTF)^10,11.

Current estimates for prevalence of postpartum anxiety range between 9% and 40%,^12-14 but are limited by utilization of self-report screening instruments rather than diagnostic tests, and short duration of follow up, with few studies reporting prevalence beyond 6 weeks.^12,15 US population data examining anxiety disorders and new-onset diagnoses are currently lacking, with most data coming from single centers, in samples that are over a decade old.¹² Additionally, the prevalence of co-occurring psychiatric diagnoses (PTSD and depression) are unknown in this vulnerable population.¹⁶ It also remains unclear whether medium- and long-term neglected medical conditions (NMC; including conditions such as pelvic floor disorders, wound complications and mastitis) and peripartum sleep disorders,^17-22, as well as neonatal or obstetric conditions are risk factors associated with postpartum anxiety.¹⁷

Epidemiologic studies exploring postpartum anxiety leveraging national US databases can help optimize timing and frequency of screening efforts, identify populations for targeted interventions, and facilitate resource allocation. The primary aim of this study was to estimate the prevalence of new-onset anxiety diagnoses in the postpartum period among commercially insured patients in the US. Secondary aims were to estimate the prevalence of co-morbid psychiatric diagnoses, describe changes by year in prevalence of these diagnoses, and identify risk factors associated with new-onset postpartum anxiety.

Methods

This retrospective population-based cohort study evaluated the prevalence, comorbidities, and risk factors associated with new-onset postpartum anxiety among US-insured patients using the Merative ^™ Marketscan^® Commercial Database of national commercial insurance claims. Claims for inpatient, andoutpatient, and pharmacy healthcare services were available from 2008 – 2022. The study protocol was reviewed and determined to be exempt by the Institutional Review Board at Stanford University School of Medicine (IRB-54362, approved 15 January 2025). We followed the RECORD guidelines for the reporting of studies using routinely collected health data.²³

We defined eligibility for the study as individuals with commercial insurance coverage during pregnancy with continuous enrollment from 3 months prior to their estimated last menstrual period through one-year after delivery. Our analysis included adult women ≥18 years of age who experienced delivery of a singleton or multiple gestation (live or stillbirth) via any delivery mode between 2008 and 2021. All codes used to define a delivery hospitalization were developed using established algorithms (Appendix 1, available online at http://links.lww.com/xxx). To minimize prevalent case bias and ensure inclusion of incident cases, individuals with a documented pre-existing (prior to pregnancy) anxiety disorder, depression, or PTSD were excluded.

The primary outcome of this study was a new-onset anxiety diagnosis in the postpartum period, defined by the presence of ≥ one anxiety disorder diagnosis associated with an inpatient or outpatient health care encounter between one-month to one-year postpartum. Diagnoses were identified using International Classification of Disease, 9^th Revision, Clinical Modification (ICD-9-CM) diagnostic and procedure codes and International Classification of Disease, 10^th Revision, Clinical Modification (ICD-10-CM) diagnostic and procedure codes for anxiety (see Supplemental Appendix 1 for list of ICD codes). The first postpartum month was excluded from the analysis to reduce temporal confounding from acute postpartum physiologic and psychologic changes.

Secondary outcomes were postpartum depression and PTSD, and co-morbid existence of these conditions with postpartum anxiety. In secondary analyses, we estimated the prevalence of postpartum anxiety by postpartum month, and anxiety, PTSD and depression co-morbid diagnoses by year. Exposures during the antepartum period through one month postpartum were examined as potential risk factors associated with the development of new-onset postpartum anxiety including demographic, obstetric, surgical and medical morbidity variables (for the index pregnancy of interest, including sleep disorders, severe maternal morbidity (SMM), as defined by the CDC²⁴, and NMC). Risk factors were selected based on biological plausibility, potential relevance to postpartum anxiety, and availability of codes in the Merative ^™ Marketscan^® Commercial Database.^25-30 Socio-demographic variables included maternal age and US region. Obstetric variables included gestational age at the time of delivery and delivery mode (vaginal or cesarean delivery). A summary of ICD codes used for identifying delivery mode, sleep disorders, SMM (as defined by the CDC²), NMC (as defined by Vogel et al.¹⁷), and infant complications (from linked infant records) and the timing of the conditions identified in this cohort are provided in Appendix 1 (available online at http://links.lww.com/xxx). All the risk factors were identified before the end of the first month after the index delivery.

We estimated the overall prevalence of any new-onset anxiety diagnoses in the postpartum period between one-month to one-year post-delivery date and provided the 95% confidence intervals (CIs). We also estimated the prevalence of any depression or PTSD disorder diagnosis by one-month intervals up to one-year following delivery. We separately examined the overall and monthly prevalence of any anxiety disorder. In our secondary analyses, we examined the overall prevalence of depression and PTSD and the prevalence of a comorbid diagnosis of postpartum anxiety disorder with depression or PTSD up to one-year postpartum. Cochran-Armitage tests were performed to test for temporal trend by year for the prevalence of anxiety, depression, PTSD, and their comorbidities.

We compared the frequency of each baseline characteristic for women with versus without an anxiety disorder diagnosis within one-year of delivery using χ² tests. We used logistic regression to estimate the unadjusted and adjusted odds ratio with 95% confidence interval for risk factors associated with an anxiety disorder diagnosis between one-month to one-year postpartum. The multivariable model included all previously identified candidate risk factors without selection based on statistical significance. There were 1.1% missing data in the US regions variable and no missing data for other variables. Complete case analysis was used in the multivariable regression.

Data were presented as percentages, unadjusted odds ratios (ORs), adjusted odds ratios (aORs) with 95% CIs, and P values. All statistical analyses were performed using STATA version 14 (StataCorp, College Station, TX). Statistical significance was set at a p value <0.05 for 2-sided tests.

Results

The numbers of eligible patients with deliveries and diagnoses resulting in the final analytic cohort are summarized in Figure 1. In total, 137,238 (8.5%) patients with pre-pregnancy or antepartum depression, anxiety or PTSD were excluded. Overall, 84,984 individuals (5.8%, 95% CI 5.7-5.8%) were diagnosed with new-onset postpartum anxiety up to 12 months following childbirth, with 9,490 who were diagnosed in the first month and 75,494 between one-month and one-year postpartum. The characteristics (demographic, obstetric, surgical and medical morbidity, and neonatal ) of patients with and without a diagnosis of postpartum anxiety are summarized in Table 1. The most prevalent NMC in patients with anxiety were chronic pain, wound or scar complications, placenta accreta spectrum, chronic anemia and surgical injury (Appendix 2, available online at http://links.lww.com/xxx). Co-morbid diagnosis of anxiety and depression occurred in 18.0 (95% CI 17.8-1.8.2) per 1000 individuals of patients without prenatal diagnoses. Co-morbid diagnosis of anxiety and PTSD occurred in 0.9 (95% CI 0.9-1.0) per 1000 individuals of patients without prenatal diagnoses.

Figure 1.

Flowchart for patients included in analysis. LMP, last menstrual period; PTSD, post-traumatic stress disorder.

Table 1.

Patient demographic, obstetric, medical and neonatal characteristics

	Postpartum new-onset anxiety from delivery to one-year postpartum n = 84,984	No anxiety n = 1,384,137	Full cohort N = 1,469,121	Standardized Mean Difference (SMD)
Demographic variables
Age mean± standard deviation	31.5±4.5	31.6±4.5	31.6±4.5	0.021
Region, per 1,000 individuals				0.064
South	419.2	398.3	399.5
North-central	234.9	226.5	227.0
Northeast	170.7	176.6	176.3
West	165.1	187.4	186.1
Unknown	10.1	11.2	11.1
Obstetric variables
Gestational age at delivery (weeks; mean± standard deviation, weeks)	38.45±1.79	38.60±1.56	38.60±1.57	0.093
Delivery mode, per 1,000 individuals				−0.093
Vaginal	659.1	702.6	700.1
Cesarean	340.9	297.4	299.9
Surgical and medical morbidity for the index pregnancy of interest, per 1,000 individuals
Sleep disorder*	13.7	4.5	5.0	−0.097
SMM combined (excluding transfusion)**	15.6	9.1	9.5	−0.059
Transfusion	7.4	4.7	4.9	−0.034
NMC combined**	356.7	293.6	297.2	−0.135
Cesarean delivery related NMC combined ***	98.9	58.9	61.2	−0.149
Neonatal variables, per 1,000 individuals
Neonatal complications combined****	36.1	27.5	28.0	−0.049
NICU admission**	38.7	28.0	28.6	−0.059

Values were presented as per 1000 individuals unless otherwise noted

^*Sleep disorder diagnosed sometime between last menstrual period through 1 month after delivery

^**SMM=severe maternal morbidity; NMC=neglected medical condition, including fistula, pelvic floor disorders, wound complications, peripartum cardiomyopathy, neuropathies, neual injury, mastitis, HIV seroconversion, chronic anaemia, placenta praevia or accrete, placenta abruption, uterine rupture, surgical site infection, pelvic adhesions, bowel obstruction, surgical injury, would scar, deep vain thrombosis, pneumonia, pain and nerve injury, menorrhagia and dysmenorrhea, chronic pain, urniray incontinuence, pelvic organs prolapse, placeta accreata/percreta, perineal pain, infections, injuries or poorlu healed perineum; NICU=neonatal intensive care

^***Cesarean delivery related NMC: Wound complication, placenta abruption, uterine rupture, surgical site infection, surgical injury

^****Neonatal complications: retinopathy of prematurity, intraventricular hemorrhage, periventricular leukomalacia, necrotizing enterocolitis, convulsions of newborn, bronchopulmonary dysplasia, sepsis, respiratory distress syndrome, hypoxic ischemic encephalopathy, neonatal cerebral depression, coma

The temporal trends in mental health diagnoses from 2008 – 2021 are presented in Figure 2. The prevalence of postpartum anxiety increased from 30.8 to 122.9 per 1000 individuals from 2008 – 2021. Similar growing trends were observed for postpartum depression, PTSD, and comorbid postpartum mental health disease diagnoses over the study period. Appendix 3 summarizes the monthly prevalences of anxiety and co-morbid diagnoses with depression and PTSD across the study cohort (available online at http://links.lww.com/xxx). New-onset anxiety diagnoses in the postpartum period were made at a median of 6 months (IQR [3-9]) following delivery.

Figure 2.

Prevalence of postpartum anxiety, depression, post-traumatic stress disorder (PTSD), and comorbidity by year of delivery. Diagnoses made from delivery to one-year postpartum. Prevalence is presented as number per 1000 individuals. P<.001 for test-for-trend analysis for all five conditions.

The multivariable model provided in Table 2 details several factors that were independently associated with a postpartum anxiety diagnosis. Risk factors included: younger maternal age, geographic variation (lower risk of postpartum anxiety in West US compared to the South and greater risk in north-central States), preterm birth (increased risk observed with earlier gestational age at delivery, cesarean delivery, antenatal and early postpartum sleep disorder diagnosed within the first month postpartum, SMM (and transfusion separately), NMC, and neonatal complications.

Table 2.

Unadjusted and adjusted models for the outcome of postpartum anxiety diagnosed from one-month to one-year postpartum

	Crude model OR (95% CI)	Adjusted model OR (95% CI)
Age (years)
<20	Ref	Ref
20-35	1.01 (0.89, 1.15)	0.79 (0.70, 0.90)
>=35	0.95 (0.83, 1.08)	0.69 (0.60, 0.78)
Region
South	Ref	Ref
North-central	0.99 (0.97, 1.01)	1.07 (1.05, 1.09)
Northeast	0.92 (0.90, 0.94)	0.99 (0.97, 1.01)
West	0.84 (0.82, 0.85)	0.90 (0.88, 0.92)
Gestational age (weeks)
37-41	Ref	Ref
32-36	1.23 (1.20, 1.26)	1.14 (1.11, 1.17)
<32	1.57 (1.45, 1.70)	1.17 (1.07, 1.28)
Delivery mode
Vaginal	Ref	Ref
Cesarean	1.20 (1.18, 1.22)	1.08 (1.06, 1.10)
Delivery year
2008	Ref	Ref
2009	1.14 (1.09, 1.20)	1.11 (1.06, 1.17)
2010	1.24 (1.18, 1.30)	1.22 (1.16, 1.28)
2011	1.33 (1.27, 1.40)	1.30 (1.25, 1.37)
2012	1.39 (1.33, 1.46)	1.37 (1.30, 1.43)
2013	1.49 (1.42, 1.56)	1.45 (1.39, 1.52)
2014	1.71 (1.63, 1.80)	1.67 (1.59, 1.75)
2015	1.98 (1.89, 2.07)	1.93 (1.84, 2.02)
2016	2.20 (2.10, 2.30)	2.22 (2.12, 2.33)
2017	2.39 (2.28, 2.51)	2.37 (2.26, 2.48)
2018	2.65 (2.53, 2.78)	2.59 (2.47, 2.71)
2019	3.06 (2.92, 3.21)	2.97 (2.84, 3.12)
2020	3.56 (3.40, 3.73)	3.47 (3.31, 3.64)
2021	3.90 (3.73, 4.09)	3.80 (3.63, 3.98)
Sleep disorder*	2.90 (2.71, 3.10)	2.68 (2.50, 2.87)
SMM (excluding transfusion)	1.67 (1.57, 1.77)	1.44 (1.35, 1.53)
Transfusion	1.51 (1.38, 1.65)	1.16 (1.06, 1.27)
NMC combined	1.33 (1.31, 1.35)	1.25 (1.23, 1.27)
Neonatal complications (combined)	1.32 (1.27, 1.37)	1.09 (1.03, 1.15)
NICU admission	1.38 (1.33, 1.43)	1.03 (0.98, 1.08)

SMM=severe maternal morbidity; NMC=neglected medical conditions; *Sleep disorder includes diagnoses made from last menstrual period to 1 month after delivery (i.e. before postpartum anxiety diagnosis)

Discussion

The main finding from this study is that approximately 6% of US commercially insured patients developed new onset anxiety within one-year of delivery. The prevalence of postpartum anxiety diagnoses increased four-fold over the 13-year study period (2008-2021) and one-third of patients with postpartum anxiety had comorbid depression. Risk factors associated with new onset postpartum anxiety included younger age, preterm birth, earlier gestational age at delivery, cesarean delivery, sleep disorders, SMM, blood transfusion, NMC and neonatal complications.

The observed prevalence of 5.8% is lower than rates reported in prospective studies using screening tools, which have estimated postpartum anxiety prevalence between 8.5% and 24.4%.^12,13 This discrepancy may be a result of the exclusion of pre-existing antenatal or pre-pregnancy anxiety diagnoses in this study. Alternatively, the discrepancy may be due to inadequate screening practices, limitations of current screening tools which are not diagnostic, and poor postpartum follow-up.³¹ A shortage of psychiatry services for postpartum patients may also affect anxiety diagnosis prevalence. A 2024 cross-sectional study found individuals in most states confronted a shortage of psychiatrists when attempting to self-refer for diagnosis and treatment.³² The increase in anxiety diagnoses over time may reflect improved recognition of perinatal mental health conditions by family practitioners and obstetricians, ICD-9 to ICD-10 code changes, improved health literacy, increased medical complexity, expansion of postpartum care beyond 6-weeks in many states, socioeconomic changes, and the COVID-19 pandemic.

The comorbidity patterns observed in our study underscore the complex interplay between perinatal mental health conditions. The 4.3% prevalence of anxiety-depression comorbidity by 2021 aligns with recent studies showing increasing diagnosis of perinatal mood and anxiety disorders, which have risen by 93.3% between 2008 and 2020.³³ Psychiatric symptoms often co-exist with one another, but the temporality of diagnoses can be difficult to determine, with other co-existing undiagnosed psychiatric disorders, PTSD for example, complicating interpretation. The relatively low prevalence of anxiety-PTSD comorbidity (0.28% by 2021) may reflect underdiagnosis rather than true prevalence, highlighting the need for improved PTSD screening in the postpartum population.

The finding of an association between cesarean delivery and postpartum anxiety, even after adjusting for confounders such as SMM and NMC, warrants further consideration. The relationship between postpartum anxiety and mode of delivery has been studied in smaller populations and on more limited time scales.^34,35 Similar to our findings these studies showed that cesarean delivery was associated with positive anxiety screening³⁴ and stress symptoms;³⁵ reduced duration of breastfeeding, and increased maternal heath care utilization were also associated with positive anxiety screening postpartum.³⁴ Several variables could not be included in the model due to lack of availability in the database, such as indication for cesarean delivery, multiple pregnancies, race and ethnicity, primary language and economic/zip code data, delivery site, clinician practices, co-morbid conditions and anesthetic complications, which may be associated with postpartum anxiety. Furthermore, the follow up protocols between delivery modes may also vary, resulting in higher diagnostic rates of anxiety following cesarean delivery compared to vaginal delivery. Nonetheless, this finding may have important implications for patient counseling and risk stratification if corroborated with prospective studies.

The relationship between NMC and postpartum anxiety adds to recent evidence highlighting the longer term effects of pregnancy-related complications on maternal mental health.¹⁷ Particularly notable was the association between chronic pain and anxiety diagnoses,^36-38 and these findings support initiatives to improve pain as a strategy to optimize mental health outcomes and conversely, the treatment of anxiety and depression may also reduce pain.

Patients with infants requiring NICU admission have previously been shown to have worse perinatal health outcomes.^39-42 Patients at risk for developing anxiety in the postpartum period may benefit from early screening with prompt referral for an early trial of cognitive behavior therapy (CBT)^43-45 and/or selective serotonin reuptake inhibitors (SSRIs) or serotonin-norepinephrine reuptake inhibitors (SNRIs).⁴⁶ Patients with postpartum sleep disorders have high rates of co-existing postpartum depression.⁴⁷ Improving sleep quality in the peripartum period has shown promise as a potential therapy for improving mood, anxiety symptoms, and fatigue.^48,49 The geographic variations in anxiety diagnoses, with lower rates in the Western United States, may reflect different screening and coding practices, regional differences in healthcare access, insurance coverage, or differences in cultural attitudes towards seeking mental health care. Intervention studies are warranted to determine whether targeted mental health support strategies in the first postpartum month for high-risk patients can reduce the subsequent development of postpartum anxiety.

A strength of this study is its large, nationwide sampling strategy with longitudinal follow-up through one year postpartum. The demographic characteristics and obstetric outcomes in our cohort are consistent with national averages for commercially insured patients, supporting the generalizability and validity of our findings within this population. However, several important limitations must be considered. Our cohort included only commercially insured patients, limiting generalizability to publicly insured or uninsured populations. Also, we acknowledge the risk for misclassification or under-ascertainment of anxiety as a potential contributing factor to the lower incidence rate of postpartum anxiety identified in our study. Finally, we did not include any treatments (e.g. pharmacotherapy or behavioral therapy) to corroborate a diagnosis of anxiety disorder in our cohort.

In conclusion, our findings indicate that new-onset anxiety diagnoses in the postpartum period following childbirth affect approximately 6% of commercially insured US patients. Determining optimal screening, referal and treatment practices for new onset postpartum anxiety may help to reduce maternal morbidity and improve postpartum recovery.