Family doctor

While most people have probably heard of postnatal depression, depression during pregnancy is a far less commonly discussed problem. It affects up to 10% of all pregnant women and is only marginally less prevalent than post-natal depression.

Depression during pregnancy is an important issue. It commonly goes under-recognised and untreated; with less than 20% of woman receiving adequate treatment. Depression can also lead to poorer health outcomes for the baby.

These include an increased risk of pre-term birth, increased risk of childhood behaviour problems and poorer cognitive development. Women with depression during pregnancy are also at a much greater risk of developing postnatal depression themselves.

Unfortunately, there is a lot of stigma surrounding the issue of depression during pregnancy with many women feeling guilty about the way they feel and not knowing how to access help. Luckily, depression is a treatable condition. Treatment can significantly improve a woman and her child’s quality of life.

Is it any different to depression outside of pregnancy?

Depression during pregnancy is defined as a sustained low mood and loss of interest in things for at least two weeks. Other symptoms include a loss or gain of appetite, changes to sleep, decreased energy and decreased concentration. See the appendix below for the ICD (International Classification of Diseases) criteria for diagnosing depression.

Care must be taken when interpreting the physical symptoms of depression in pregnant women because changes in appetite or fatigue for example may not be due to an underlying depression but may in fact represent the normal changes of the body during pregnancy.

Pregnancy is also associated with an increased risk of conditions that can mimic depression such as thyroid problems and iron deficiency anaemia which can also contribute to depressive symptoms. It is important to rule these out before making a diagnosis of depression. Blood tests can readily measure thyroid hormone levels, iron and haemoglobin levels.

How do we treat it?

The treatment of depression in pregnancy is determined by its severity. Depression can be classified into mild, moderate or severe, depending on the symptoms the patient experiences. Severity is also determined by the functional impact that depression has on a woman’s life.

In mild depression, cognitive behavioural therapy(a form of counselling/psychological intervention) and lifestyle modifications can be just as effective as medication. For moderate to severe cases, treatment with a selective serotonin reuptake inhibitor (SSRI) is the most common, first-line treatment. This is usually combined with psychological therapies for increased efficacy.

Most SSRIs have a very low risk profile during pregnancy, the only SSRI that is not typically recommended is Paroxetine.

For Women who have taken antidepressants in the past:

Switching antidepressants during pregnancy or lactation is not generally recommended. The period of switching may increase the chance of relapse and the evidence is not strong enough to suggest that any one antidepressant is more beneficial during pregnancy than another. If women have responded well to treatment with a particular antidepressant in the past, then the safest option for mother and baby is to remain on that antidepressant rather than change and risk relapse.

What are the non-drug treatments available?

Mild depression can benefit from gentle psychological treatments such as guided self-help. These sorts of therapies are readily available online or through reading material. Other advice surrounding sleep hygiene, exercise and healthy eating habits can help to improve symptoms.

Mild to moderate depression typically responds better to more rigorous psychological therapy such as CBT. However, access to this can often be delayed due to long waiting times in the public sector. Your family doctor should be able to direct you to alternatives in the area you live.

The therapy itself can take up to 12 weeks to have positive effects.

When should antidepressants be used?

Antidepressants are normally indicated in moderate to severe depression. Like any drug, the risks and benefits need to be assessed before making a decision to start therapy. The positive physical effects of SSRIs are typically seen after two-three weeks of treatments such as increased energy and better sleep. The full improvement in mood is usually seen after 4-6 weeks of treatment.

The threshold to treat depression in pregnancy tends to be higher because of concerns about fetal safety. It is also important to balance these alongside the evidence that untreated maternal depression can have negative consequences on the health and development of the baby.

While SSRIs are commonly used safely during pregnancy, the studies that have tested this are of varying quality. They are mostly observational studies which are notoriously poor at determining causation and even the best studies in the field have their weaknesses.

Nevertheless, it appears as though women who take antidepressants during pregnancy are not at an increased risk of spontaneous abortion compared with those without depression. Studies do not suggest an increased risk of stillbirth or perinatal death with use of SSRIs in pregnancy. They do not suggest an increased risk of congenital malformation, despite poorer, smaller studies associating paroxetine in particular with a small increased risk of heart defects.

The main known risks associated with SSRI use in pregnancy are that:

• They may increase the risk of postpartum haemorrhage

• Associations have been made between low birth weight and preterm birth

• They may increase the risk of pulmonary hypertension of the newborn (significantly increased blood pressure in the lungs leading to respiratory distress) although because this is such a rare condition the absolute risk of this remains very small.

One syndrome that has been linked to SSRI use in pregnancy is neonatal adaptation syndrome (NAS). This is most commonly associated with antidepressant use (particularly paroxetine) in late pregnancy. It is usually self-limiting and severe complications such as seizures are very rare.

Symptoms of NAS usually last for about 3 days and can include:

• Insomnia

• Agitations, tremors, shivering

• Restlessness or irritability

• Poor feeding, vomiting or diarrhoea

• Dysregulated termperature control

• Seizures (rare)

Despite these potential negative side effects, it is important to recognise the positive benefits of SSRI therapy which include improved mood, increased energy, better sleep and feeling pleasure in things again. This benefit, in the form of a more active, engaged mother is passed on to the baby. Preventing postnatal depression is also important and prevention can have incredibly positive effects on both mother and baby.

What about breast feeding?

SSRIs are compatible with breast feeding; with less than 10% of the maternal dose passed into breast milk. This is 5-10 times less than the exposure inside the uterus.

Appendix 1.

ICD-10 criteria for depressive episode

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

• Disturbed sleep


• Diminished appetite

References:

1. Vigod, Simone N, Claire A Wilson, and Louise M Howard. "Depression In Pregnancy". BMJ (2016): i1547. Web. 12 Apr. 2016.