Hairfall during pregnancy as shared by @DrBhavi Mody
It's due to hormonal changes that occur during pregnancy. But you shud rule out medical causes:
Check for iron levels, thyroid, Vit D and B 12 levels.
What you can do-

1.Start Homeopathy it helps curb hair fall.

Also use Arnica shampoo or any organic shampoo and oil regularly.

Start with 2.Follihair tablets.

3.Take good care of nutrition.

Up ur protein intake.

Have plenty of veggies n fruits

Increase your fluid intake.

4.Don't use any harsh products and colours.

Refrain from ironing or treatments.

Don't blow dry.

Don't comb when hair is wet

5.Stress less n sleep well.

Get some ME time.