Facebook and Apple are giving female staff the opportunity to delay plans to start a family by paying for them to freeze their eggs.
The firms are covering up to US$20,000 (€15,812) for the procedure and annual storage costs, according to reports.
The employment perk is expected to help the companies attract more women into the male-dominated sector, in the face of concerns over workforce diversity.
It is also set to be seen as a further sign of the so-called "perk arms race" as Silicon Valley firms battle to recruit and retain top talent.
Facebook recently began covering the costs of egg freezing and Apple will begin in January, NBC said.
In a statement, Apple said it "cares deeply about our employees and their families, and we are always looking at new ways our health programs can meet their needs."
"We continue to expand our benefits for women, with a new extended maternity leave policy, along with cryopreservation and egg storage as part of our extensive support for infertility treatments," the firm said.
"We also offer an adoption assistance program, where Apple reimburses eligible expenses associated with the legal adoption of a child."
'Not a guarantee of a successful pregnancy'
However, experts point out freezing eggs is a relatively new procedure that does not guarantee a successful pregnancy.
Corey Whelan, of the American Fertility Association, said: "It's really, really important for women to know it's not a guarantee of motherhood."
"Some women consider it an iron-clad insurance policy. It's not."
The procedure is gaining popularity as more women put motherhood on hold.
A post on the online forum eggsurance.com says: "Women today are at a cultural and generational crossroads. We have the same career expectations and demands as men."
"As our biological clocks tick away, we must establish ourselves in the workplace, find the right mate and become financially secure enough to establish a family."
Microsoft reported earlier this month that only 29% of its staff were women, while at Google it was 30%. Some 31% of Facebook employees are women, but just 15% are in technical jobs.
