A breech birth is when a baby is born bottom first instead of head first. Around 3-5% of pregnant women at term (37–40 weeks pregnant) have a breech baby.

Most babies in the breech position are born by a caesarean section because it is seen as safer than being born vaginally.

Doctors and midwives in the developing world have thus lost many of the skills required to safely assist women giving birth to a breech baby vaginally.

Delivering all breech babies by caesarean section in developing countries is difficult to implement as there are not always resources available to provide this service.

With regard to the fetal presentation during pregnancy, three periods have been distinguished.

During the first period, which lasts until the 24th gestational week, the incidence of a longitudinal lie increases, with equal proportions of breech or cephalic presentations from this lie.

During the second period, lasting from the 25th to the 35th gestational week, the incidence of cephalic presentation increases, with a proportional decrease of breech presentation. The second period is characterized by a higher than random probability that the fetal presentation during this period will also be present at the time of delivery.

In the third period, from the 36th gestational week onward, the incidence of cephalic and breech presentations remain stable, i.e. breech presentation around 3-4% and cephalic presentation approximately 95%.

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