LYNN – Teen births spiraled dramatically downward in Massachusetts while the number of Caesarean sections reached an all-time high, according to a study released Tuesday by the state Department of Public Health (DPH).The report contained several key findings. Among them: that teen births in the state have hit an all-time low, while the so-called C-section deliveries soared to unparalleled heights.DPH data compiled in 2005 n the latest available ? indicates that the state’s teen birth rate was 46 percent below the national rate, or 21.7 births per 1,000 for women ages 15-19 years old.Inversely, the C-section delivery rate was the highest ever reported in Massachusetts. One out of every three births, or 32 percent, involved a C-section. As a result, the C-section rate in Massachusetts is 7 percent higher than the U.S. rate.Dr. Allyson Preston, chief of obstetrics and gynecology at North Shore Medical Center, said C-section rates are up throughout the U.S.”The C-section rate is trending up nationally, and I think that partially has to do with the legal climate,” she said. “Another part of it has to do with the fact that more women are opting to have repeat C-sections if that was the procedure for their previous delivery.”Preston noted that a small percentage of C-sections are due to breach births.”But that represents a very small number,” she said.At the Birthplace at Salem Hospital, which services Salem and surrounding communities, there were 1,853 deliveries during the fiscal period beginning in October 2005 and ending Sept. 30, 2006. Of those, 31.4 percent were C-sections, according to Preston.Comparing statistics from The Birthplace to the DPH files is difficult because the Salem numbers include women under age 19 rather than including age 19.”So they might not be analogous,” Preston said.Nonetheless, the rate of delivery to young women under age 19 at The Birthplace is 38 per 1,000.The DPH study also found that the overall number of births in Massachusetts declined by 2 percent in 2005.On a disheartening note, the infant mortality rate among black, non-Hispanic women was twice as high as that among white non-Hispanic women, or 9.4 deaths versus 4.3 deaths per 1,000 live births.Births by teenage Hispanic women were far more common than their white counterparts. For instance, the teen birth rate for Hispanic women was almost six times higher than for white non-Hispanics, or 73.2 percent compared to 12.9 percent per 1,000 women ages 15 to 19.The percentage of multiple births also remained inordinately high. In 1990, 1 out of 38 births was a multiple. In 2005, the rate jumped to 1 out of every 22.According to the DPH, the Massachusetts teen birth rate declined by 37 percent from 1990-2004. In general, Massachusetts enjoyed a significantly lower overall teen birth rate during that period, compared to the U.S. average.For example, the overall Massachusetts adolescent birth rate for 2004 was 22.2 births per 1,000 for women ages 15-19, compared to the national rate of 41.2.In what could be viewed as a positive trend, teen birth rates among all race and ethnic groups in Massachusetts have declined over the past decade.In 2004, of all live births to Massachusetts resident teens, 46.7 percent or 2,128 were to white non-Hispanic mothers; 32.9 percent or 1,499 were to Hispanic mothers; 13 percent or 591 were to black non-Hispanic mothers; 3.3 percent or 152 were to Asian mothers; and 4 percent or 184 were to mothers categorized as other.Nonetheless, Hispanic teens represent approximately 10 percent of the overall population, and black non-Hispanic teens approximately 7 percent. Considering these population numbers, the two groups are “significantly over-represented” in these birth statistics, according to DPH.While great strides have been made in decreasing the teen birth rate among all race and ethnic groups, there has not been uniform success. Black, non-Hispanic teens have had the greatest decrease in birth rates ? 50 percent from 199