Abstract:
Background: The incidence of twin pregnancy is increasing all over the world because of assisted reproductive
technology or spontaneously as a result of numerous risk factors. It is associated with increased risk of maternal and
neonatal complications both in the developed and developing countries, which in turn increase financial, emotional,
personal and social costs to the twins themselves and their families. Thus, determining its magnitude and identifying
the risk factors are crucial for possible prevention and better interventions.
Method: Hospital-based prospective and case-control studies were conducted. To determine the incidence of
twin pregnancy, all the 3812 deliveries conducted from December 01, 2012 to November 30, 2013 at Jimma
University Specialized Hospital were followed from the time of admission to labor ward to the expulsion of fetus. To
identify the risk factors for twin pregnancies, all 144 twin deliveries happened were taken as cases and 288 controls
were randomly selected from the 3668 singleton-deliveries happened, with the ratio of 1:2. All the necessary data
were collected by interviewing mothers, for both the cases and controls, by using structured questionnaire. The data
were analyzed by using SPSS for windows version 20.0. Multivariate logistic regression analysis was done to
identify risk factors for twin pregnancy. Odds ratios with 95% confidence intervals were used as measure of
associations.
Results: From 3812 deliveries conducted in the year period, 144 were twins making an incidence of 37.7 per
1000 deliveries. Family history of twinning (OR=9.16, 95% CI: 4.73, 17.74), oral contraceptive pill use prior to
pregnancy (OR=2.14, 95% CI: 1.12, 4.08), household monthly income of 50-100 USD (OR=1.94, 95% CI: 1.08,
3.50) and >100 USD (OR=2.18, 95% CI: 1.10, 4.33) were found to increase the risk of twin pregnancy significantly.
Conclusion: The study found high incidence of twin pregnancy. Family history of twinning, household income of
≥50 USD and oral contraceptive use prior to pregnancy were identified as risk factors for twin pregnancy. Mothers
with identified risk factors should be targeted by nearby health facility in order to make the diagnosis of twin
pregnancy earlier so that complications can be picked earlier and managed.
