China remains the United States' most accessible source of adoptions from overseas, thanks to an efficient system and strong oversight of orphans, according to two experts.

The number of foreign adoptions by US families has fallen to the lowest level in three decades. However, adoptions of Chinese children by US citizens rose 15 percent year-on-year in 2015 to 2,354.

The figure accounted for 42 percent of all foreign adoptions, according to the US Department of State.

Beth Alpert and her adopted daughter Yang Yingying returned to Anhui to look for the girl's biological mother. Dai Wenxue / For China Daily