Crying at a television advert and then laughing about crying is a recognisable part of pregnancy and is not what this page is about. It is about the distinction between that and something quieter, which is easier to miss precisely because it makes less noise.
The short answer: emotional lability — swings within a day, tearfulness, irritability, sudden shifts — is normal and is driven by very high oestrogen and progesterone on top of exhaustion and a major life change. What is not normal is mood that stops moving: persistently low most of the day, most days, for two weeks or more, with loss of interest in things you normally enjoy. Duration, not intensity, is the test. Thoughts of harming yourself need a same-day call.
Why it happens
Oestrogen and progesterone reach concentrations in pregnancy that have no equivalent in ordinary life, and both are neuroactive — they act directly on the systems that regulate mood, sleep and stress response. That alone would produce emotional volatility.
Then everything else is added. Sleep is broken from the first trimester onward. Nausea makes eating irregular, and irregular eating destabilises mood on its own. The body is changing in ways that are not always welcome. Work continues. And there is a large, irreversible, not-entirely-controllable event approaching, which most people are expected to describe as exciting.
Where the line sits
| Mood swings | Worth raising | |
|---|---|---|
| Movement | Shifts through the day — low, then fine | Flat most of the day, most days, for two weeks or more |
| Pleasure | Still enjoy the things you enjoy | Nothing gives pleasure, including things that always did |
| Self-view | Frustrated at being emotional | Worthless, guilty, a failure, or a burden to others |
| Function | Unchanged | Withdrawing, missing appointments, not managing work or home |
| Future | Anxious about it | Cannot picture it, or do not want to be here for it |
| Sleep | Broken by the bump, the bladder, reflux | Waking early and unable to return, with a flat mood |
The confounder is that half of the right-hand column has an innocent pregnancy explanation — poor sleep, low energy, appetite change. That is why the useful markers are the ones pregnancy does not explain: loss of pleasure, self-blame, and being unable to picture the future.
Call the same day if: you have thoughts of harming yourself; you feel unable to keep yourself safe; you have thoughts about harming the baby that do not feel unwanted and intrusive; or you feel confused, unusually elated or agitated, or are hearing or seeing things that others do not. Out of hours, use your maternity unit's number or emergency services. Every one of these is treated as urgent by whoever answers, and none of them will be met with judgement.
What helps
- Say it in a sentence you prepared. "I don't think this is just hormones" is enough, and it is the sentence that evaporates in the room if you have not written it down.
- Protect sleep and eating first — both destabilise mood, and both are more fixable than the hormones.
- Move daily, even briefly. Physical activity has real evidence in mild to moderate depression and is safe in an uncomplicated pregnancy.
- Tell one person who is not a clinician. Isolation is the thing that makes all of this heavier, and pregnancy is unusually isolating for something so public.
- Do not stop existing medication because you are pregnant — ask first. See the anxiety page.
Mood swings in pregnancy — at a glance
Very high oestrogen and progesterone act directly on the brain systems regulating mood, and they arrive alongside broken sleep, irregular eating, a changing body and a major irreversible life event — so tearfulness, irritability and swings within a single day are ordinary. The dividing line from antenatal depression is duration rather than intensity: a persistent low mood most of the day, most days, for two weeks or more, with loss of interest or pleasure in things normally enjoyed. Because poor sleep, low energy and appetite change all have innocent pregnancy explanations, the markers that carry the most information are the ones pregnancy does not explain — anhedonia, self-blame and being unable to picture the future. Antenatal depression is common, under-detected, treatable, and treating it in pregnancy matters for the postnatal period too. Raising it leads to a conversation and a questionnaire, not to a judgement about parenting. Thoughts of harming yourself, or thoughts about the baby that do not feel unwanted, need a same-day call.
Inside Baby Novum: the daily check-in records mood, sleep and energy together and the app includes the EPDS questionnaire with a reminder to repeat it. "Has it been every day or some days" is the question that decides what happens next, and six weeks of entries answer it properly. Encrypted on the device, no account, no server copy.
Frequently Asked Questions
Why are my emotions all over the place in pregnancy?
Oestrogen and progesterone rise to levels far beyond anything outside pregnancy, and both act on the brain systems that regulate mood. On top of that: exhaustion, nausea, disrupted sleep, a changing body, and a genuinely enormous life change that has to be processed while carrying on as normal. Tearfulness, irritability and sudden shifts between joy and dread are all ordinary in that combination.
What is the difference between mood swings and depression?
Movement. Mood swings move — up in the morning, flattened by the afternoon, laughing by the evening. Depression sits still: a persistent low mood most of the day, most days, for two weeks or more, with loss of interest or pleasure in things you normally enjoy. Intensity is not the test. Someone can sob for twenty minutes and be fine, and someone can feel flatly nothing for a month and be seriously unwell.
Is depression in pregnancy common?
Yes, and it is under-detected for the same reason antenatal anxiety is: the symptoms overlap with normal pregnancy — poor sleep, low energy, appetite change — and the expectation that pregnancy is a happy time makes people edit what they report. Antenatal depression is treatable, and treating it in pregnancy matters for the postnatal period too.
What will happen if I tell my midwife I am struggling?
A conversation, usually a short questionnaire such as the EPDS, and a discussion of options — talking therapy, support, and where appropriate medication. It is part of routine antenatal care, not an exceptional event. It does not trigger any assessment of your ability to parent. Clinicians are considerably more worried about people who say nothing.
When is a mood change an emergency?
Thoughts of harming yourself, feeling unable to keep yourself safe, or thoughts about harming the baby that do not feel unwanted and intrusive — those need a same-day call, and out of hours use your maternity unit or emergency services. Also urgent: feeling confused, unusually elated or agitated, hearing or seeing things others do not, or having beliefs others find strange, which need assessing quickly.