A growing number of marriages between Singaporean men and Vietnamese women are ending speedily in annulment, lawyers say.
Some men claim their wives ran away just days after the wedding, before consummating the marriage.
Many have told lawyers their brides refuse to have sex, demanded payment for it, or said sex would have to wait until after the women obtain permanent residence here.
One man saw a lawyer to dissolve his marriage after his bride asked for $80 to have sex the first time.
Most men feel the women just want to work here, and are not interested in the marriage.
Some annulments are initiated by the Vietnamese women too, also on the grounds of non-consummation of the marriage.
The Sunday Times checked with 10 lawyers who handle family matters. Most have seen a sharp rise in the number of annulments involving Vietnamese women in recent years.
They also said that over the past few years, the number of annulments involving Vietnamese women far outnumbered cases where the women were of other nationalities, such as those from China, Myanmar and Thailand.
There is no breakdown by nationality in publicly available data on annulments.
The issue of Vietnamese women and their short-lived marriages has been reported in Vietnam itself. In August, Tuoi Tre newspaper had a report headlined "When foreign husbands fall victim to Vietnamese brides".
It said that some Vietnamese sought foreign husbands in countries such as China and South Korea, and would walk out when they were not happy and look for another foreign husband.
The report said these women wanted foreign husbands "merely for money" and some had been married three times in short order.
In Singapore, lawyer Gloria James-Civetta, who handles a few such cases a month - double what she used to see - told The Sunday Times: "I feel that some of these women are using marriage to get into Singapore, to either look for a better match (than the man they married) or to find work here."
"It's very common for the men to tell me that their Vietnamese wives do not want to have sex with them until they get permanent residency."
A blue-collar man in his 30s told her he had to wait for sex while he applied for permanent residency for his Vietnamese wife. When the application was rejected and his bride refused to consummate the marriage for a few months, he decided to annul the union.