An all-day, multi-county event tomorrow seeks to educate mothers, fathers and anyone who might plan to have children, about sexually-transmitted diseases.

The Lower Hudson Valley Perinatal Network will host its second annual community health day which will include events at more than 200 hospitals, community centers, libraries, health departments and doctors’ offices in Westchester, Rockland, Putnam and Dutchess counties.

“You want to make sure you have the best chance of having a healthy birth. If you have a sexually transmitted disease and you get pregnant, you are more likely to have a baby born too small or too soon,” said Cheryl Hunter-Grant, executive director of the perinatal network, which is based at the Westchester Medical Center.

This year’s program — “It takes a village … to address the risk. Give babies a healthy start” — will aim to raise awareness about chlamydia, the human papillomavirus, or HPV, gonorrhea, HIV, syphilis and herpes among people of childbearing age.

The rates for sexually transmitted diseases rose between 2003 and 2007 in the Lower Hudson Valley and in New York State.

Chlamydia, a curable infection caused by the bacteria chlamydia trachomatis, is the most common. In 2007, there were 2,484 cases in Westchester, 589 in Rockland and 65 in Putnam, according data from the New York State Department of Health’s Bureau of Sexually Transmitted Disease Control.

Chlamydia tops the list of communicable diseases in Westchester and Rockland counties.

Today’s event will stress the importance of getting tested for STIs and STDs before getting pregnant.

Participating hospitals in the Perinatal Network event include Putnam Hospital Center in Carmel, Good Samaritan Hospital in Rockland, Phelps Memorial Hospital in Sleep Hollow, St. John’s Riverside Hospital in Yonkers. Other sites include pediatricians’ offices, gynecologists offices, nursery schools, day care centers, Wal-Mart parking lots, day laborer centers, community centers and various clinics throughout the counties.

For more information on the Lower Hudson Perinatal Network, visit their Web site at www.lhvpn.net

To find a participating Community Health Day site, call (914) 493-6435.