New cases of pregnant women with laboratory evidence of Zika virus infection were down for the 2 weeks ending Feb. 7, with a big drop in the U.S. territories offsetting an increase among the 50 states and the District of Columbia, according to the Centers for Disease Control and Prevention.

There were 146 new cases of Zika infection reported in pregnant women over that period, compared with 233 over the previous 2 weeks. Of the new cases, 85 were reported in the U.S. territories (down from 186) and 61 were reported in the 50 states and D.C. (up from 47), the CDC reported. These are not real-time estimates, the CDC noted. They reflect only the number of reports received, so the cases may have occurred during earlier reporting periods.

For 2016-2017, there have been 4,611 cases of Zika virus infection in pregnant women in the United States: 1,455 in the states/ D.C. and 3,156 in the territories, the CDC said.

Of the cases in the states/D.C., 1,047 pregnancies have been completed with or without birth defects. There have been 43 liveborn infants with Zika-related birth defects and five pregnancy losses with Zika-related defects, the CDC said. The number of liveborn infants was up from 38 for the previous 2-week span, which was the largest increase since mid-November.

The Zika caseload for all Americans is 42,063 (from Jan. 1, 2015 to Feb. 15, 2017), of which 5,040 cases were reported in the 50 states/D.C. and 37,023 were reported in the territories (98% in Puerto Rico), the CDC reported.

Zika-related birth defects reported by the CDC could include microcephaly, calcium deposits in the brain indicating possible brain damage, excess fluid in the brain cavities and surrounding the brain, absent or poorly formed brain structures, abnormal eye development, or other problems resulting from brain damage that affect nerves, muscles, and bones. The pregnancy losses encompass any miscarriage, stillbirth, and termination with evidence of birth defects.