When investing in unit trusts or investment-linked policies (ILP), you would find in the list of fund choices fund names with the term “SGD-H” or “Hedged SGD”. What does this mean?

A hedge is an investment to reduce the risk of adverse price movements in an asset. Normally, a hedge consists of taking an offsetting position in a related security.
What is a hedge?, Investopedia.com
It could look something like: SGD-H. This means that the fund’s underlying exposure is hedged to the SGD. When you buy a unit trust with a SGD-hedged share class, you are in effect hedging your exposure (from the fund’s underlying exposure) to the SGD. The fund you purchase may be invested in the European credit markets, whereby securities there are denominated in the EUR. Thus, your currency risk as a Singapore-based investor would be to the EUR, and the value of your investment would be exposed to the fluctuations of the EURSGD exchange rate. By adopting a SGD-hedged class of the fund, you can lower your risk of a weakening of the EUR against the SGD eroding your investment returns from the European credit market.
Unit Trusts: Differences Between The Various Share Classes, Fundsupermart.com.
For Singaporean investors, a SGD-hedged fund allows you to invest in a fund that is denominated in another currency, while lowering your risk of the currency weakening.
Should you invest in such a fund? It depends on your objective, your risk appetite and other preferences and considerations. It is best to discuss with your financial planner/advisor before choosing such a fund.