Before maternity leave there was talk of promotion, but when I returned it was off the cards

I have a PhD in science and worked as a research scientist at one of the biggest British companies. I was a high flyer and was verbally promised a promotion several times, but it didn’t happen immediately due to organisational changes. A month before I disclosed my pregnancy, my boss was very sure about putting me forward for promotion that year, and positive about my chances of success. Before I went on maternity leave, I worked very hard right up to the last minute and came back after just six months. When I returned nothing was said about my promotion. Instead, everything was stagnant and frustrating. I decided to leave and the UK to come to work in Scandinavian where there is much more gender parity, although there is still not complete equality.