Health issues have forced Georgia Hall and Charley Hull to withdraw from the England team that will compete this week in the Hanwha Lifeplus International Crown in San Francisco.
Alice Hewson and Liz Young will join the English squad that also features Jodi Ewart Shadoff and Bronte Law.
Hall revealed she has been suffering with her foot and in a statement said: "I've been struggling with my foot for the past few weeks and in spite of daily physio treatment it's not improving, so I've been advised to take a week off.
"I'm really sorry not to be able to play the Hanwha Lifeplus International Crown and wish my England team-mates the very best of luck for the week."
For Hull, it is stomach issues that have led to her withdrawal.
In a statement she added: "I've been quite sick the past couple of weeks with stomach issues. I was hoping I could play through it but it seems not and I'm going to need to seek some help.
"I'm really sorry to let the tournament down and of course my team-mates, but I'm going to have to take some time out to get healthy."
The United States team of Nelly Korda, Lexi Thompson, Lilia Vu and Danielle Kang are the top seed for the event that runs Thursday through Sunday at TPC Harding Park. The US squad will compete in Group A along with No 4 Sweden, No 5 England and No 8 China.
The defending champion South Korean squad of Jin Young Ko, Hyo-Joo Kim, In Gee Chun and Hye Jin Choi are seeded second. South Korea top Group B, which also will include No 3 Japan, No 6 Thailand and No 7 Australia.
For round-robin group play, each team will face every other team in their group in a fourball (better-ball) match. The top two teams in each group advance to the semi-finals, which will each feature two singles matches one foursomes (alternate-shot) match.
The final and the third-place match will follow the format used in the semi-finals.
You can watch the Hanwha Lifeplus International Crown live on Sky Sports from Thursday May 4, with coverage on Sky Sports Golf and Main Event from 11pm.