Dr Stephen Chiew Siong Lin any feedbacks on him?

I don't have direct experience with him, but for a high risk pregnancy you really want to weigh a few things: how responsive the gynae is to questions between appointments, whether they are hospital-based at somewhere like KKH or Mount Elizabeth where there is strong support, and whether you feel comfortable asking them anything without feeling rushed. Since there are no reviews here yet, it might be worth posting again or checking the main Facebook group to see if anyone has seen him specifically. If you can get a first consult just to feel him out, that is honestly the best way to know if his style suits you for something as important as a high risk pregnancy.