Related substances (GC) (Sum of peaks with a relative retention less than that of benzyl alcohol) â¤ 0.02 %: Related substances (GC) (Sum of peaks with a relative retention greater than that of benzyl alcohol) â¤ 0.20 %: Related substances (GC) (disregard limit) â¤ 0.0001 %: Benzene (GC) â¤ 0.0002 %: Chlorobenzene (GC) â¤ 0.01 %: Toluene (GC)
If you're carrying more than one baby, chances are good you'll deliver early. Twins are usually born around 36 weeks -- four weeks early. Triplets arrive at about 33 weeks, and quads often make their debut at 31 weeks.
Monoamniotic twins occur when the split takes place after the ninth day after fertilization. Conjoined twins: When the division of the developing zygote into 2 embryos occurs, 99% of the time it is within 8 days of fertilization. Mortality is highest for conjoined twins due to the many complications resulting from shared organs.