 Which factor is the best predictor of necessity for an emergency C-section on a fetus?
Obstetrics for beginners It's my first go at delivering a baby by caesarean section – and the foetal head is impacted, jammed in its mother's pelvis. She comes with a vulva, a pre-cut incision in her abdomen and, most importantly, a uterus containing a foetal head that should, in the normal way of things, be free to emerge between her legs. To understand the desperation of Debra and how the Tydeman tube might help to relieve it requires a brief foray into basic obstetric knowhow. For the baby's head to get stuck on the way out may not be usual, but it's by no means a rarity. The standard response is to perform a caesarean section. Every year some 160,000 babies are born in the UK this way, with almost two thirds of them classified as emergencies. One audit has suggested that roughly 8,000 babies get stuck and have to be delivered by caesarean at a stage when their mothers are fully dilated. "Some of the babies will be so close to coming out by the normal route," says Tydeman, "that it's then difficult to get them back up and remove them through the hole in the woman's tummy." Which women are most at risk of this setback seems to be largely unpredictable. "We just observe that it happens… It's been discussed in the medical literature since the 1940s, but until 10 years ago, and throughout my training and most of my life as a consultant, it wasn't really talked about."
 There is no agreed upon factor
 Father's birth weight  Mother's birth weight  Practitioner's level of experience  There is no agreed upon factor