Exposure to passive smoking during pregnancy increases the risk of congenital anomalies by 13% or still birth by 23%. This research has been conducted by the Nottingham University.

The health hazards of smoking during pregnancy are well established. It can lead to- fetal mortality, low birth weight (LBW), premature birth, cleft palate, club foot or cardiac problems. These problems are due to exposure to tobacco toxins. Since second hand smoking also involves exposure to the same toxins just in lower proportions. Therefore passive smoking is also likely to cause similar complications.
Source-Medindia