The Harvard Medical School will under the nations' first large-scale investigation of the side-effects of birth control pills, it was announced yesterday.

It will conduct the study in cooperation with the Worcester Foundation for Experimental Biology.

Dr. Gregory G. Pincus '21, of the Worcester Foundation and Dr. David D. Rutstein '30, head of the Medical School's Department of Preventive Medicine, will use Ford Foundation Grants totalling $367,000 to investigate the effects of oral contraceptives on liver and blood conditions and the menstrual cycle.

The Harvard-Worcester study will involve approximately 10,000 women in Haiti and Puerto Rico, half of whom have been using birth control pills and half vaginal contraceptives. Pincus has been working with the groups since 1956, looking for signs that birth control pills repress cervical cancer. For the last four years Dr. Rutstein has been responsible for organizing this experiment and analyzing data.

Now, with the Ford Foundation grants, Rutstein and Pincus will be able to broaden their investigation. Interest will center on whether or not there is a higher thrombophlebitis (inflammation of a vein associated with clotting) among women using oral contraceptives, than among those using other forms.

Thrombophlebitis is rare, but is sometimes fatal and it was a major point of concern in the Government's report on birth control released earlier this year.

Pincus and Rutstein also plan to keep records of women who have stopped taking the pills in order to analyze any possible after-effects. An increase in fertility seems to be one, Pincus said.