Boys Cause More Problems During Labor

Is it a boy or a girl? New parents might be able to guess their baby's gender just by the difficulty of the delivery, according to a new study.

Research published in this week's issue of the British Medical Journal found that women are more likely to encounter complications during labour and delivery when they are having a boy.

The study took place in the National Maternity Hospital in Dublin and used data from the delivery ward database during 1997 to 2000. The study included mothers who were pregnant for the first time with a single birth and who spontaneously went into labor at full term.

In the study period, 4,070 male and 4,005 female infants were analyzed. Male infants were significantly more likely to require oxytocin, a hormone that stimulates contractions. They were also more likely to need blood sampling, forceps or Caesarean section.

Researchers said male infants have significantly larger heads than female infants, and this may contribute to longer labor and the higher instance of Caesarean section. But this factor would not fully explain the differences, since length of labor alone would not account for the increased blood sampling in boys, which is needed when a fetus is suspected to be in distress.

"What this study does show is that when we say 'it must be a boy' as a humorous explanation of complications of labor and delivery, we are scientifically more correct than previously supposed," the researchers wrote.