Title: Induction of Labour vs Expectant Management for Pregnancies beyond 40 Weeks of Gestation a Prospective Comparative Randomised Study
Authors: Dr Poonam Kumari, Dr Sipra Singh, Shazia Iqbal
DOI: https://dx.doi.org/10.18535/jmscr/v7i5.137
Abstract
Introduction
Term pregnancy is defined as pregnancy lasting between 37 completed weeks and 41 weeks + 6 days. Pregnancy that reach or continue beyond 294 days (42weeks) are described as post terms. Prolonged pregnancy is between 41 – 42 weeks and occurs in approximately 5 – 10% of pregnancies. The estimated date of confinement or due date for normal pregnancy is calculated as 38 weeks after conception or 40 weeks after first day of normal LMP (assuming 28 days menstrual cycle). The Commonest cause is error in calculation of gestational age. Nulliparity, advanced age, obesity are the strongest risk factors. Before deciding the best course for the management of prolonged pregnancy it is imperative to reconfirm the gestational age by a dating scan performed in first half of pregnancy. Increasing availability of USG has significantly improved accuracy of pregnancy dating and detection of fetal anamolies, so extremely long gestations are rare. WHO recommends a policy of routine induction of labor at 41 completed weeks. An earlier induction can potentially expose the mother to a greater risk of operative intervention and subsequent morbidity, while delaying induction increases chances of fetal distress and perinatal morbidity.
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