1. There are around 103 million women pregnant in the world at any one time.
According to the CIA World Factbook there are on average 255 worldwide births per minute, and as a pregnancy on average lasts 280 days (= 403,000 minutes), this means that there are on about 103 million women pregnant in the world at any one time. (detailed calculation here).
2. Longest pregnancy on record is 375 days.
The average pregnancy lasts 280 days, and most women if they run much over will be induced but according to Time Magazine, and other online sources, the longest recorded pregnancy in history was 375 days, with a healthy baby born in 1945. Prior to this the longest recorded pregnancy that resulted in a healthy birth was 317 days.
3. Nigeria has highest rate of twins in the world.
In Europe we have a birth rate of twins of 9-16 per 1000 live births, in Nigeria the figure is 45-50 per 1000 live births. Research has been carried out in this region and some have attributed this higher rate to the yams that they eat.
4. Heaviest baby born was 10.8kg.
A baby boy was born to Anna and Martin Bates in 1879 that weighed 10.8kg (23lb 12oz), according to Guinness World Records, sadly this baby only lived 11 hours. The heaviest surviving baby was 10.2kg (22lb 8oz), a boy born in Italy in 1955.
5. Eight is the highest number of babies to all survive a multiple birth.
Nadya Suleman, nicknamed “Octomum” gave birth to octuplets in 2009 in the United States. They are the first in which all eight survived infancy. Her multiple birth and similar cases of septuplets have all been attributed to fertility treatments. The highest number of babies to survive a multiple birth without fertility treatments is six.
6. Youngest mum ever was 5 years old.
The youngest girl ever reported to have given birth was 5 years old in Peru in 1939. Her baby was born by cesarean section and survived. She had apparently been having periods since she was 3 years old (a medical condition known as precocious puberty). Her father was arrested for incest.
7. One mum gave birth to 69 children,
Mrs Feodor Vassilyev gave birth to a total of 69 (67 of whom are said to have survived) children between 1725 and 1765, she had 27 births and she gave birth to 16 sets of twins, 7 sets of triplets and 4 sets of quadruplets. See a list here of large families.