For most, the abundance of oestrogen causes a slowing down of hair shedding, and many women report increased volume and lustrous locks during pregnancy. But this isn’t so for all – the relative stress to the body in the first trimester may cause hair loss, but this is only evident later in the pregnancy. This will come back – you’ll notice regrowth two to four months after baby is delivered.
Your oestrogen adjusts to normal levels after delivery, and this relative drop can cause shedding which was put on hold in pregnancy to resume. This feels like you’re losing lots of hair and can be distressing (along with so much else to cope with as your body and your life changes). But it’s just a readjustment, your hair is returning to its usual pre-pregnancy state.
Pregnancy can prompt new thyroid problems: hyperthyroidism (overactive thyroid gland) or, less commonly in pregnancy, hypothyroidism (underactive thyroid gland). Symptoms of these can be difficult to spot as your body changes in pregnancy, but if you have substantial weight changes, changes to your hair or skin, your heart feels like it’s beating hard, fast, slow or irregular, these are all reasons to visit your doctor for a blood test. Pregnancy causes a mild anaemia and this is expected, but significant iron deficiency or iron deficiency anaemia, can cause hair loss – this may be a reason to see your doctor. Both of these conditions can cause fatigue or, in the case of hyperthyroidism, sleep disturbance. Again, it’s very hard to tease this apart from pregnancy symptoms, but be aware that other conditions can complicate your pregnancy.
See your doctor if you have hair loss in pregnancy with substantial changes to your weight, concerns about your heart rate, or you think your tiredness is disproportionate. If you've been pregnant before, you may be able to compare, and if there's any family history of thyroid problems or an autoimmune disease, discuss this with your doctor. They can examine your hair and send you for blood tests. Chemical hair regrowth products such as Regaine are available to buy, but should be avoided in pregnancy and during breastfeeding.