Depression in pregnancyBMJ 2016; 352 doi: https://doi.org/10.1136/bmj.i1547 (Published 24 March 2016) Cite this as: BMJ 2016;352:i1547
- Simone N Vigod, assistant professor, psychiatrist, and Shirley Brown clinician scientist1,
- Claire A Wilson, academic clinical fellow2,
- Louise M Howard, NIHR research professor, professor in women’s mental health, and consultant perinatal psychiatrist2
- 1Department of Psychiatry, Faculty of Medicine, University of Toronto; Women’s College Hospital and Women’s College Research Institute, Ontario, Canada M5S 2B1
- 2Section of Women’s Mental Health, King’s College London, London, UK
- Correspondence to: S N Vigod
What you need to know
Offer all women education about mental health problems in pregnancy, treatment options, and the effect on themselves and their offspring
Offer women with mild or moderate depression psychological treatments if they have access to them and can commit time to therapy
Consider antidepressant drugs such as selective serotonin reuptake inhibitors (SSRIs) for women with current or past severe or recurrent depression
For pregnant women who have not used antidepressants, any SSRI (with the exception of paroxetine) is a reasonable first choice
For former antidepressant users, information on efficacy and tolerability must be considered when selecting an antidepressant during pregnancy
Switching antidepressants during pregnancy or lactation is not recommended (even with paroxetine) as there is no clear evidence that the safety profile of one drug is superior to that of another. Switching away from an effective drug could increase the risk of relapse
Depression in pregnancy affects up to 10% of women, with higher rates in low and middle income countries, a rate only slightly lower than in the postpartum period.1 2 Yet, as few as 20% of pregnant women with depression receive adequate treatment.3 4 This is problematic because depression can profoundly affect a woman’s sense of wellbeing, relationships, and quality of life. Untreated or incompletely treated depression can also have adverse consequences for the offspring. Systematic reviews show an increase in markers of infant morbidity such as preterm birth, childhood emotional difficulties, behaviour problems, and, in some studies, poor cognitive development.5 6 Antenatal depression also is one of the strongest risk factors for postnatal depression, a condition linked to developmental problems in children.6 7 Severe depression can result in suicide, a major cause of maternal death.8 9 Perinatal suicides have been associated with lack of active treatment.10 Barriers to treatment include stigma, lack of provider training on perinatal mental health, and limited access to the evidence based psychological treatments that patients prefer.11 12 13 Women report that conflicting information from professional and non-professional sources about antidepressant drugs in pregnancy impedes decision making and may reduce treatment uptake.14 15 16 17 18 19 This review presents evidence for health professionals to enable shared management of depression in pregnancy with patients.20
Sources and selection criteria
We searched PubMed, Embase, PsycINFO, and the Cochrane Library without language restrictions. Searches were done between 1 January 2003 and 17 October 2015 using the key search terms “pregnancy”, “prenatal”, “antenatal”, “postnatal”, “postpartum”, “perinatal”, “puerperal”, “breastfeeding”, “birth”, “weaning”, “childbirth”, “trimester”, “peripartum”, “lactation”, “ante-natal”, “post-natal”, “post-partum” and “mood disorder” (exploded MeSH term), “depression”, and “treatment”, “intervention”, “prevention”, “trial”, “therapy”, “therapeutic”, “treat”, “medicine”, “medication”, “prescribe”, “prescription”. Using date restrictions based on the amount of research output in each area, between 1 January 2010 and 16 October 2015 we combined these search terms with specific terms for antidepressant drugs commonly used in primary care for selective serotonin reuptake inhibitors, serotonin-norepinephrine (noradrenaline) reuptake inhibitors, and other first line antidepressant drugs. We supplemented the search with information from the authors’ personal libraries and evidence based national guidelines.
How is depression in pregnancy identified?
The core features of a depressive episode are a sustained low mood or loss of interest in pleasurable activities for at least two weeks (box 1). This persistence of symptoms helps to distinguish depression from sadness or a temporary response to stress. The mood disorders chapter of ICD-10 (international classification of diseases, 10th revision) has no antenatal specifier for depression. However, there is a separate code for disorders occurring in the puerperium (six weeks after delivery). This contrasts with the Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5), which denotes a “with perinatal onset” specifier for major depressive episodes with onset during pregnancy or within four weeks post partum.22Box 2 lists the risk factors for depression in pregnancy, although women can present with none. The National Institute of Health and Care Excellence recommends that all health professionals discuss physical and mental health with women at each contact during pregnancy.23 Standardised tools recommended by NICE that may help identify depression include:
Box 1: Criteria for depressive episode
ICD-10 criteria for depressive episode21
At least two weeks (but shorter periods may be reasonable if symptoms are severe and of rapid onset) of the following core symptoms experienced with severe intensity for most of every day:
Depressed mood. The mood change is normally accompanied by an overall change in level of activity
Loss of interest and enjoyment
Reduced energy leading to increased fatigue and diminished activity (this also could be a physical symptom of pregnancy)
Other common symptoms:
Reduced concentration and attention
Reduced self esteem and self confidence
Ideas of guilt and unworthiness
Bleak and pessimistic views of the future
Ideas or acts of self harm or suicide
DSM-5 criteria for depressive episode22
A: For the same two week period at least five of the following symptoms have been present, where at least one is either depressed mood or loss of interest or pleasure in activities.
Depressed mood most of the day or almost every day, indicated by subjective self report or by reports of others. This mood might be characterised by sadness, emptiness, or hopelessness
Noticeably diminished interest or pleasure in all or almost all activities most of the day, nearly every day
Clinically significant weight loss when not dieting, or weight gain
Inability to sleep or oversleeping nearly every day
Psychomotor agitation or retardation nearly every day
Fatigue or loss of energy nearly every day
Feelings of worthlessness or excessive or inappropriate guilt (which may be delusional) nearly every day
Diminished ability to think or concentrate, or indecisiveness, nearly every day
Recurrent thoughts of death (not just fear of dying), recurrent suicidal ideation without a specific plan, or a suicide attempt or specific plan for committing suicide
B: Symptoms cause clinically significant distress or impairment in social, occupational, or other important areas of functioning
C: The episode is not due to the effects of a substance or a medical condition
DSM-5 denotes a “with perinatal onset” specifier for major depressive episodes with onset during pregnancy or within four weeks post partum
Box 2: Risk factors for antenatal depression
Several risk factors for depression in pregnancy have been identified.7 Clinicians should remember that depression in pregnancy can occur in the absence of any of these risk factors.
Risk factors with medium and large associations with antenatal depression, and strong evidence in systematic reviews:
History of mental disorders
Life stress and major or negative life events
Low socioeconomic status
Risk factors with smaller or inconsistent associations with antenatal depression in systematic reviews:
Poor social support
Young maternal age
• a two question screen: “During the past month, have you often been bothered by feeling down, depressed, or hopeless?” and “During the past month, have you often been bothered by little interest or pleasure in doing things?” (a validation study of this tool for depression in pregnancy is currently under way)24 25
• the 10 question Edinburgh postnatal depression scale, where in a recent review of validation studies for antenatal depression, estimates for sensitivity and specificity varied between 64% and 100% and 73% and 100%, respectively, suggesting acceptable validity.26 27
Tools with questions about appetite, fatigue, or sleep (eg, patient health questionnaire, PHQ9) must be interpreted cautiously, as impairment might reflect the physical effect of pregnancy rather than depression.28 Regardless of the screening tool used, a clinical diagnostic interview is required to confirm depression and identify comorbid problems requiring management. In particular, clinicians should identify and treat any medical problems that could be causing or contributing to the depressive symptoms, such as thyroid abnormalities, iron deficiency, and nausea and vomiting of pregnancy.
Depression can coexist or overlap with other conditions, such as anxiety, obsessive-compulsive disorder, trauma, and stressor related disorders. In women with depression, health professionals must establish whether there is a history of hypomanic or manic symptoms, as the management of depression with bipolar disorder differs.29 Psychosis, in the form of psychotic depression or a primary psychotic disorder such as schizophrenia would also require specialised management.
Factors such as domestic violence, obesity, smoking, and substance misuse are also associated with depression. These may need to be addressed to reduce the risk of a negative effect on offspring.7 30 NICE has produced guidelines on the assessment and management of these conditions, including during pregnancy.23 31 32 33
How is it treated?
Treatment for depression is based on the severity of the presenting illness, as recommended in the NICE pathway for common mental disorders in primary care.34Figure 1⇓ provides an example of a stepped care framework. Box 3 outlines suggestions to determine the severity of the depression. A woman’s treatment may begin at any step in the pathway, depending on the severity of her illness. The NICE guidelines on antenatal and postnatal mental health recommend that all pregnant women with depression, regardless of severity, receive education from their treating provider about depression, including how to recognise symptoms and the short and long term effects on mothers, children, and families.23 Clinicians should explore the severity of depressive symptoms with the women, and review treatment preferences to make shared decisions about treatment. Invite partners and other members of the support system to join management discussions whenever possible.
Box 3: Determining the severity of a depressive episode using ICD-10 criteria35
Assessment of severity relies on clinical judgment and the number, type, and severity of symptoms:
Mild depression—presence of at least two core symptoms and two additional common symptoms (see box 1)
Moderate depression—presence of at least two core symptoms and three (preferably four) additional symptoms
Severe depression—presence of all three core symptoms and at least four additional symptoms, some of which should be severe. There is a greater risk of suicidality and somatic symptoms (changes to appetite and sleep are common). A severe episode may or may not be accompanied by psychotic symptoms, but the presence of such symptoms generally indicates a more severe presentation
Another useful indicator of severity is the degree of functional impairment experienced by the patient
Which non-drug treatments are effective?
Women with mild depression may benefit from psychological treatments such as guided self help, whereas women with mild and moderate depression may benefit from higher intensity psychological treatments such as cognitive behaviour therapy (CBT) or interpersonal therapy.36 Primary care and antenatal care providers must be aware of the referral systems in their jurisdictions. Assessment should be offered in a timely manner as delays in treatment result in more maternal distress and longer exposure of the fetus to depression. Access to psychological therapies is often limited in low resource settings. Efforts to train peers and community members to deliver some lower intensity psychological treatments for perinatal depression in developing countries have been successful.22 27 28 29 30 31 32 33 34 36 37 38 39 Research is under way to explore novel modes of delivery of psychological care for perinatal depression, including guided self help for mild symptoms and telephone based interpersonal therapy for mild and moderate depression.40 41
Few studies have focused specifically on the efficacy of psychosocial and psychological therapies in pregnant women with depression. Systematic reviews of high quality trials in non-pregnant women found face to face structured time limited psychotherapies such as CBT and interpersonal therapy to be as effective as drugs for mild, and sometimes moderate, depression.42 43 Similarly, randomised controlled trials in postpartum women have shown these treatments to be more effective at reducing depressive symptoms than usual postpartum care.44 Several small pilot studies of CBT and interpersonal therapy for pregnant women in high income countries are promising, showing a moderate effect on depressive symptoms, but larger studies are required to be able to generate stable estimates of efficacy.36 45 46 47 48 49 Two recent pilot randomised controlled trials reported improved infant outcomes in CBT treated versus non-treated groups.49 50 In low and middle income countries, meta-analyses of psychosocial and psychological interventions delivered during pregnancy and post partum by trained primary care and community health workers showed similar efficacy.7 A Cochrane systematic review evaluated bright light therapy, acupuncture, massage, and supplementation with omega-3 (six randomised controlled trials) but concluded that evidence was insufficient to recommend these in clinical care.51
How should antidepressants be used?
Owing to concerns about fetal safety, the threshold for drug interventions is higher during pregnancy. However, for women with current (or former) severe depression (many of whom are taking antidepressants before pregnancy), or for those who do not respond to psychological therapies alone—or do not want to wait the 12 or more weeks for treatments typically to take effect—antidepressants will usually be necessary.23 Selective serotonin reuptake inhibitors (SSRIs) are first line drugs in pregnancy for unipolar depression, but serotonin-norepinephrine (noradrenaline) reuptake inhibitors, buproprion, and mirtazapine are also commonly used when there is historical response to these drugs or non-response to SSRIs.23 Women who do not respond to first line treatments, have multiple psychiatric comorbidities, or have bipolar disorder may require referral and management in secondary (specialty) psychiatric care. In severe depression, hospital stay may be required, particularly for women with active suicidal ideation, treatment resistance, or psychotic clinical features.
Women not taking antidepressants before pregnancy
Antidepressants should be offered for severe and moderate depression when psychological therapy is not, or has not been, effective or where such therapy is not available.23 Antidepressants should be used along with psychological therapies whenever possible because combination therapy may lead to higher remission rates and lower relapse rates compared with either therapy alone.24 52 People with moderate and severe depression benefit most, and symptoms can begin to improve, within two weeks of starting drugs.53 54 For women with no previous antidepressant use, any SSRI is a reasonable first choice, with the possible exception of paroxetine owing to its higher risk of neonatal adaptation syndrome (NAS, see box 4) and withdrawal symptoms in the mother.56 57 For former antidepressant users, previous efficacy and tolerability must be considered when selecting antidepressants during pregnancy.
Box 4: Neonatal adaptation syndrome
Symptoms of neonatal adaptation syndrome (NAS) tend to begin within 48 hours of birth, are usually short lived (median three days), and last no longer than four weeks from birth.55 Symptoms can include:
Agitation, tremors, or shivering
Restlessness or irritability
Poor feeding, vomiting, or diarrhoea
Dysregulated temperature control
Tachypnoea, respiratory distress, nasal congestion, or cyanosis (rare)
Women with a history of depression and receiving maintenance antidepressants
Evidence suggests that continued antidepressant use may prevent relapse of depression in pregnancy, although the greatest prophylactic effect is in women with severe or recurrent depression.58 59 Switching antidepressants during pregnancy or lactation is not recommended (even with paroxetine) as there is no clear evidence that the safety profile of one drug is superior to that of another, and switching from an effective drug could increase the risk of relapse.
Dosage in pregnancy
For all antidepressants, offer the lowest but most effective dose. The aim of treatment with antidepressants is to achieve complete remission of symptoms. There is no evidence that reducing antidepressant dose before delivery reduces the risk of neonatal adaptation syndrome60 (see box 4). Pharmacokinetic changes of pregnancy may alter drug metabolism and the impact of this is variable and unpredictable. As such, changes to dosage should only be made in the case of symptom relapses where a dose may be too low or, in the case of side effects or toxicity, too high. SSRIs are considered compatible with breast feeding as less than 10% of maternal dose passes into breast milk (5-10 times less than in utero exposure).61 Therefore, the choice of antidepressant during pregnancy need not be influenced by plans for lactation, except in the case of women who have never used antidepressants who may want to start sertraline given that it seems to pass least into breast milk.61 62
What advice should be given about antidepressant use in pregnancy?
Women should be reminded that no pregnancy is without risk, irrespective of drug use, and that decisions about antidepressants involve weighing the benefits and harms of all treatment options, including no drugs. Pregnant women with depression, and their infants, may be at higher risk of poorer outcomes than the background population and this should be considered during any conversation about antidepressant treatment.5 Data on safety come from observational studies of variable quality. Even the most high quality studies are imperfect, so it is important to make women aware that some degree of uncertainty remains about the absolute safety of antidepressants in pregnancy.63 64Figure 2⇓ shows an approach that clinicians can use to help women weigh potential benefits and harms of antidepressant treatment in pregnancy.
Effects of antidepressants in pregnancy
Maternal health and pregnancy outcomes
To date it seems that women who take antidepressants in pregnancy have a similar risk for spontaneous abortion compared with women without depression.66 67 68 Well conducted studies also suggest no increased risk for stillbirth or perinatal death with antenatal use of SSRIs.69 70 Two large population based studies found no increased risk for hypertensive disorders in pregnancy from use of SSRIs in pregnancy among women with psychiatric disorders, although serotonin-norepinephrine reuptake inhibitors were associated with a small increased risk in one study.71 72 73 Serotonergic antidepressants may increase the risk for postpartum haemorrhage, but in one study blood loss volume was only slightly greater in women using SSRIs compared with non-users (484 v 398 mL).74 75
Data on infant outcomes are reasonably reassuring. Antenatal use of antidepressants does not seem to be associated with an increased risk of major congenital malformations. Early studies reported a small absolute increased risk for specific cardiac defects (especially with paroxetine),76 but this is not supported by more rigorously conducted studies.77 78 Associations with both preterm birth and low birth weight have been observed, but a recent meta-analysis found the magnitude of the effect to be small (mean difference −0.45 weeks’ gestation, 95% confidence interval −0.64 to −0.25 weeks’ gestation; and −74 g birth weight, 95% confidence interval −117 g to −31 g).66 79 Persistent pulmonary hypertension of the newborn is rare (1 per 1000 live births) but is a potentially fatal condition for the neonate. In pregnancies exposed to SSRIs the absolute risk is 2 or 3 per 1000 live births, although one well conducted study found that the risk increase attributable to SSRIs (as opposed to confounding factors) was likely to be small.80 81
A neonatal adaptation syndrome (NAS) has been consistently described with use of most antidepressants during late pregnancy (box 4). Incidence ranges from 5% to 85% as symptoms are variably defined across studies.82 NAS is usually mild and self limiting; a meta-analysis reported mean Apgar scores 0.2 points lower for infants exposed compared with not exposed to antidepressants.66 Severe complications such as neonatal convulsions are rare (<0.1% of births).35 There is no known method for preventing NAS due to exposure to antidepressants during pregnancy. Lowering the dose of antidepressants before delivery does not seem to lower the risk for NAS.60 Reduction of antidepressant dosage before delivery is therefore not generally recommended since this may also render the dose ineffective for protecting the mother against relapse of depression at the time of highest risk (early postpartum period).
Guidelines for fetal and infant monitoring vary, but generally involve a recommendation for monitoring for NAS around the time of delivery.23 Simple supportive measures such as advice about regular feeding and reassurance are usually sufficient for management. Parents should be encouraged to use skin-to-skin contact to aid temperature regulation. Severe signs of toxicity, although rare, may warrant more proactive treatments, such as anticonvulsants, fluid resuscitation, and respiratory support.
Less research has focused on long term outcomes in children, where it is difficult to disentangle the effects of antenatal use of antidepressants from shared maternal-child genetic susceptibility or postnatal environmental factors such as maternal depression.83 Small studies provide weak evidence of motor and language delays associated with antenatal use of SSRIs and venlafaxine that are not thought to be clinically significant.84 85 86 87 88 89 90 One sibling controlled study found no association between antidepressant use in pregnancy and childhood internalising and externalising psychiatric symptoms at age 18 months, although anxiety symptoms were increased at age 3 years in those exposed to antidepressants during the antenatal period.91 Early case-control studies suggested a relation between exposure to antidepressants during the antenatal period and risk of autism, but neither a large well conducted cohort study nor a sibling controlled cohort study found evidence of an increased risk.92 93
What is the long term prognosis?
An estimated 50% of people with one episode of depression have another, and 80% of those will have chronic or recurrent episodes.94 The highest risk for relapse is likely to be in those women with greater severity of illness and especially if symptoms are not treated to remission. When antidepressants are effective during the initial phase of treatment, maintenance treatment may reduce the risk of relapse by about 50%, and this may be improved further with continued combination psychological and drug treatments in women with severe illness.95 The current recommendation for people with a first episode of depression is maintenance treatment for at least six months to one year, and longer for those with multiple or severe episodes.95 Some evidence suggests that women who have episodes of depression in pregnancy or post partum may have recurrent depression at other times of hormonal change, such as during the perimenopause.96 Long term follow-up for women with depression in pregnancy is therefore required, with specific attention to subsequent pregnancies and other reproductive life events, such as perimenopause.
Questions for future research
What is the effectiveness of psychological interventions for mother and infant?
What is the effectiveness of non-invasive somatic interventions for mother and infant?
Treatments for women with previous or current severe depression in pregnancy that allow for effective treatment without systemic drug exposure of the infant are currently being evaluated, including focal brain stimulation therapies such as repetitive transcranial magnetic stimulation (rTMS), transcranial direct current stimulation (tDCS),98 99 100 bright light therapy, sleep deprivation, and sleep phase advance101
Can an interactive electronic patient decision aid reduce decisional conflict about antidepressants and improve maternal outcomes?
Online and interactive patient decision support tools are being investigated that aim to enhance women’s knowledge about depression in pregnancy and its treatment options, help women to clarify their values about the benefits and risks of each treatment, and support women in decision making with their healthcare providers102 103
How can we assess the risks and benefits of antidepressant treatment on infant and child outcomes, and what are the moderators of treatment?
Most studies have focused on the safety of antidepressant treatment for infants and children, without addressing how treatment might benefit infant and child outcomes. Studies that deal with both of these issues, as well as research that identifies who is likely to benefit most from which treatment are essential to informing the risk-benefit discussion about the use of antidepressants in pregnancy. Current trials include a randomised controlled trial of women randomly allocated to relapse prevention cognitive therapy with gradual, guided discontinuation of SSRIs under clinical management (intervention group) compared with continuation of SSRIs (control group)104
What role can technology play in screening for depression in pregnancy?
Administering screening tools through mobile devices is currently being trialled.105 This may provide greater access to screening tools to identify the high numbers of women who go undiagnosed and provide prompt access to treatment
Can cost effective psychosocial interventions be delivered within resource poor settings?
Methods currently being evaluated include task sharing to community health workers to deliver a counselling intervention in South Africa106
Tips for non-specialists
Although pregnancy is often a happy time, depression is common. Do not forget to ask how your patient finds being pregnant whenever you see her and then ask specific questions about low mood, lack of enjoyment, and loss of interest
See pregnant women alone at least once during the pregnancy as they may feel unable to tell you about problems with their partner if the partner is present (particularly if domestic violence is occurring), and may not disclose depressive symptoms if friends or family are present
Reassure women that depression is common and treatable, and discuss the range of treatment options. When referring for psychological interventions, ensure services know when a woman is pregnant so she is seen quickly (NICE guidance recommends assessment within two weeks)
Provide women with information resources (see resources for patients)
Additional educational resources
Resources for healthcare professionals
NICE. Antenatal and postnatal mental health: clinical management and service guidance for clinicians (www.nice.org.uk/guidance/cg192/resources/antenatal-and-postnatal-mental-health-clinical-management-and-service-guidance-35109869806789)—guidance on treatment of a range of perinatal conditions
Maternal Mental Health (www.knowledge.scot.nhs.uk/maternalhealth/learning/maternal-mental-health.aspx)—e learning resource for all healthcare professionals working with pregnant women outlining the key principles in recognition and management of mental illness during this period (requires free registration)
Bettercare Maternal Mental Health Handbook (http://ls.bettercare.co.za/maternal-mental-health/0-3-contents.html)—resource for all healthcare professionals working with pregnant women
Maternal Mental Health: A Handbook for Health Workers (http://mhinnovation.net/sites/default/files/downloads/resource/PMHP%20Handbook%202013.pdf)—advice of particular relevance to those professionals working in low and middle income countries
Thinking Healthy (http://mhinnovation.net/sites/default/files/downloads/resource/WHO_Thinking%20Healthy_eng.pdf)—a manual for psychological management of perinatal depression—an evidence based approach to provision of low intensity psychological interventions that can be implemented by community workers, particularly in low and middle income countries
Resources for patients and carers
NICE. Mental health in pregnancy and the year after giving birth (www.nice.org.uk/guidance/cg192/resources/mental-health-in-pregnancy-and-the-year-after-giving-birth-250640652229)—information on treatment of a range of perinatal conditions
UK Royal College of Psychiatrists. Mental health in pregnancy (www.rcpsych.ac.uk/healthadvice/problemsdisorders/mentalhealthinpregnancy.aspx)—fact sheet for women (also available in Urdu and Spanish)
Tommy’s. Your mental wellbeing in pregnancy (www.tommys.org/pregnancy/your-life/mental-health)—advice and resources produced by the charity Tommy’s
US Department of Health. Depression during and after pregnancy (www.womenshealth.gov/publications/our-publications/fact-sheet/depression-pregnancy.pdf)—useful fact sheet
Postpartum progress (www.postpartumprogress.com/)—a blog about emotional health around pregnancy and childbirth run by a non-profit organisation in the United States
How patients were involved in creating this article
We asked women with experience of perinatal mental health problems who are on a perinatal service user and carer advisory panel funded by a National Institute for Health Research research professorship (NIHR-RP-R3-12-011) to LMH and a patient representative in Canada (advisory for SNV) to comment on the content of this article. Comments and suggestions were incorporated in the final iteration from Clare Dolman, Sarah Spring, Maria Bavetta, Amanda Grey, Ceri Rose, Ben Parry, and S Farrell.
Contributors: LMH and SNV planned the content of the manuscript. CAW conducted the literature searches underlying evidence in the paper. SNV and LMH drafted the manuscript; all authors edited the manuscript and approved the final version. SNV is the guarantor and accepts full responsibility for the work and/or the conduct of the study, had access to the data, and controlled the decision to publish.
Competing interests: We have read and understood the BMJ policy on declaration of interests and declare the following: SNV holds funding from the Canadian Institutes of Health Research and The Hospital for Sick Children Foundation to conduct two of the randomised controlled trials mentioned in this manuscript (NCT02308592; NCT02116127). LMH receives funding from the National Institute for Health Research (NIHR), including for two randomised controlled trials mentioned herein (NCT02308592; http://public.ukcrn.org.uk/search/StudyDetail.aspx?StudyID=17048) (NIHR research professorship in maternal mental health (NIHR-RP-R3-12-011) and NIHR programme grant for applied research (RP-PG-1210-12002) on the effectiveness of perinatal mental health services). She chaired the NICE update on Antenatal and Postnatal Mental Health Guidance (CG192) and she is also the National Clinical Advisor on the NICE/NCCMH technical advisory group for the NHS England access and waiting time perinatal mental health programme.
Provenance and peer review: Commissioned; externally reviewed.